Pouech, P., Duchaine, F. and Poinsot, T. (2021) Premixed flame ignition in high-speed flows over a backward facing step, Combustion and Flame, 229, doi: 10.1016/j.combustflame.2021.111398

[bibtex]

@ARTICLE{AR-CFD-21-14,
author = {Pouech, P. and Duchaine, F. and Poinsot, T. },
title = {Premixed flame ignition in high-speed flows over a backward facing step},
year = {2021},
number = {Article 111398},
volume = {229},
doi = {10.1016/j.combustflame.2021.111398},
journal = {Combustion and Flame},
abstract = {Ignition plays a major role in combustion science and the ignition sequences are a crucial element in many engines. The current study focuses on ignition in subsonic, high-speed flows of premixed methane/air mixture. The Minimum Ignition Energy (MIE) is first evaluated for quiescent and constant speed flows to analyze its dependency on the flow speed and the value of this speed beyond which ignition can not be achieved anymore. To be able to obtain flame ignition and stabilization at higher flow velocities, ignition by a spark placed in the recirculation zone of a backward facing step is studied. For a range of inlet velocities, Direct Numerical Simulation (DNS) is used to measure the energy required for flame stabilization and analyze ignition sequences. Results show that a flame kernel is first created in the low-speed recirculation zone for all speeds. However, the subsequent flame propagation away from the recirculation zone depends on the flow speed: while low-speed cases produce a global ignition, high-speed cases can lead to quenching when the flame tries to leave the recirculation zone and enter the high-speed region, leading to global ignition failure. DNS also allows to propose and verify criteria for ignition in terms of flow speed and spark energies: following scaling arguments by Shanbhogue et al. (2009) for flame stabilization over obstacles, a simple Damkohler number is shown to control the success of ignition. Finally, DNS results are used to investigate mechanisms controlling the success or failure of the ignition sequence: they show that heat losses to the combustor walls play a limited role while flame stretch on the flame elements leaving the recirculation zone have a major influence.
},
keywords = {Ignition, High-speed flows, Premixed flame, Backward facing step}}

Dupuy, D., Perrot, A., Odier, N., Gicquel, L.Y.M. and Duchaine, F. (2021) Boundary-condition models of film-cooling holes for large-eddy simulation of turbine vanes, International Journal of Heat and Mass Transfer, 166, pp. 120763, doi: 10.1016/j.ijheatmasstransfer.2020.120763

[bibtex]
[url]

@ARTICLE{AR-CFD-21-2,
author = {Dupuy, D. and Perrot, A. and Odier, N. and Gicquel, L.Y.M. and Duchaine, F. },
title = {Boundary-condition models of film-cooling holes for large-eddy simulation of turbine vanes},
year = {2021},
volume = {166},
pages = {120763},
doi = {10.1016/j.ijheatmasstransfer.2020.120763},
journal = {International Journal of Heat and Mass Transfer},
abstract = {In many industrial applications, the mechanical integrity of a surface operating under large thermal loads is ensured by injecting a cold fluid through a series of hole along the surface, forming a thin film of cool fluid shielding the solid surface from external heat. An accurate prediction of the heat transfer provided by these so-called film-cooling systems is crucial to ensure the durability of the cooled surfaces. However, the large-eddy simulation of film-cooling systems is complex and expensive because the in-hole flow must be meshed and simulated. To address this difficulty, the modelling of the film-cooling jet by mean of a dedicated boundary condition has recently been proposed. This paper investigates several potential improvements for this type of model in four geometries: an inclined cylindrical hole, a fanshaped hole and two fanshaped laidback holes. The analysis focuses on the comparison of a spatially uniform injection to a model taking into account velocity and temperature spatial variations at the hole exit. The study also compares a non-turbulent injection to a model with synthetic turbulence injection. The comparisons are first performed using a fine mesh to validate the approach, then using a coarse mesh representative of a mesh that could be used to simulate a cooled nozzle guide vane. The results show that both spatial inhomogeneity and turbulence injection significantly improve the cooling effectiveness predictions in a wide variety of cases. The spatial inhomogeneity is especially crucial for the near-hole behaviour of the flow while turbulence injection is particularly important when the destabilisation of the jet by the crossflow is not sufficient to immediately trigger transition. Using a very coarse mesh, the turbulent mixing is observed to be underestimated with all examined boundary-condition models and the behaviour of the jet is not correctly described for some of the configurations investigated. Although not sufficient, non-negligible improvements are nevertheless obtained with an inhomogeneous turbulent injection compared to the baseline uniform model.
},
keywords = {Film cooling, Large-eddy simulation, Modelling},
url = {https://www.sciencedirect.com/science/article/abs/pii/S0017931020336991}}

Odier, N., Thacker, A., Harnieh, M., Staffelbach, G., Gicquel, L.Y.M., Duchaine, F., Garcia-Rosa, N. and Mueller, J.-D. (2021) A mesh adaptation strategy for complex wall-modeled turbomachinery LES, Computers and Fluids, 214, pp. 104766, doi: 10.1016/j.compfluid.2020.104766

[bibtex]
[url]

@ARTICLE{AR-CFD-21-18,
author = {Odier, N. and Thacker, A. and Harnieh, M. and Staffelbach, G. and Gicquel, L.Y.M. and Duchaine, F. and Garcia-Rosa, N. and Mueller, J.-D. },
title = {A mesh adaptation strategy for complex wall-modeled turbomachinery LES},
year = {2021},
volume = {214},
pages = {104766},
doi = {10.1016/j.compfluid.2020.104766},
journal = {Computers and Fluids},
abstract = {A mesh adaptation methodology for wall-modeled turbomachinery Large Eddy Simulation (LES) is proposed, simultaneously taking into account two quantities of interest: the average kinetic energy dissipation rate and the normalized wall distance y+. This strategy is first tested on a highly loaded transonic blade with separated flow, and is compared to wall-resolved LES results, as well as experimental data. The adaptation methodology allows to predict fairly well the boundary layer transition on the suction side and the recirculation bubble of the pressure side. The method is then tested on a real turbofan stage for which it is shown that the general operating point of the computation converges toward the experimental one. Furthermore, comparison of turbulence predictions with hot-wire anemometry show good agreement as soon as a first adaptation is performed, which confirms the efficiency of the proposed adaptation method.
},
keywords = {Wall-modeled large-eddy simulation, Mesh adaptation, Complex turbomachinery, Hot-wire anemometry, Turbulence assessement},
url = {https://www.sciencedirect.com/science/article/pii/S0045793020303364}}

Pérez-Arroyo, C., Dombard, J., Duchaine, F., Gicquel, L.Y.M., Martin, B., Odier, N. and Staffelbach, G. (2021) Towards the Large-Eddy Simulation of a full engine: Integration of a 360 azimuthal degrees fan, compressor and combustion chamber. Part I: Methodology and initialisation, Journal of the Global Power and Propulsion Society, Special Issue: Data-driven modelling and high-fidelity simulations, pp. 1-16, doi: 10.33737/jgpps/133115

[bibtex] [pdf]

@ARTICLE{AR-CFD-21-68,
author = {Pérez-Arroyo, C. and Dombard, J. and Duchaine, F. and Gicquel, L.Y.M. and Martin, B. and Odier, N. and Staffelbach, G. },
title = {Towards the Large-Eddy Simulation of a full engine: Integration of a 360 azimuthal degrees fan, compressor and combustion chamber. Part I: Methodology and initialisation},
year = {2021},
volume = {Special Issue: Data-driven modelling and high-fidelity simulations},
pages = {1-16},
doi = {10.33737/jgpps/133115},
journal = {Journal of the Global Power and Propulsion Society},
abstract = {Optimising the design of aviation propulsion systems using computational fluid dynamics is essential to increase their efficiency and reduce pollutant as well as noise emissions. Nowadays, and within this optimisation and design phase, it is possible to perform meaningful unsteady computations of the various components of a gas-turbine engine. However, these simulations are often carried out independently of each other and only share averaged quantities at the interfaces minimising the impact and interactions between components. In contrast to the current state-of-the-art, this work presents a 360 azimuthal degrees large-eddy simulation with over 2100 million cells of the DGEN-380 demonstrator engine enclosing a fully integrated fan, compressor and annular combustion chamber at take-off conditions as a first step towards a high-fidelity simulation of the full engine. In order to carry such a challenging simulation and reduce the computational cost, the initial solution is interpolated from stand-alone sectoral simulations of each component. In terms of approach, the integrated mesh is generated in several steps to solve potential machine dependent memory limitations. It is then observed that the 360 degrees computation converges to an operating point with less than 0.5% difference in zero-dimensional values compared to the stand-alone simulations yielding an overall performance within 1% of the designed thermodynamic cycle. With the presented methodology, convergence and azimuthally decorrelated results are achieved for the integrated simulation after only 6 fan revolutions.},
keywords = {interaction, LES, compressor, combustion chamber, fan, gas-turbine engine},
pdf = {https://cerfacs.fr/wp-content/uploads/2021/06/CFD_Perez-Arroyo_Towards-the-Large_Eddy-part1_J.gpps_.global21-68.pdf}}

Pérez-Arroyo, C., Dombard, J., Duchaine, F., Gicquel, L.Y.M., Martin, B., Odier, N. and Staffelbach, G. (2021) Towards the Large-Eddy Simulation of a full engine: Integration of a 360 azimuthal degrees fan, compressor and combustion chamber. Part II: Comparison against stand-alone simulations, Journal of the Global Power and Propulsion Society, Special Issue: Data-driven modelling and high-fidelity simulations, pp. 1-16, doi: 10.33737/jgpps/133116

[bibtex] [pdf]

@ARTICLE{AR-CFD-21-69,
author = {Pérez-Arroyo, C. and Dombard, J. and Duchaine, F. and Gicquel, L.Y.M. and Martin, B. and Odier, N. and Staffelbach, G. },
title = {Towards the Large-Eddy Simulation of a full engine: Integration of a 360 azimuthal degrees fan, compressor and combustion chamber. Part II: Comparison against stand-alone simulations},
year = {2021},
volume = {Special Issue: Data-driven modelling and high-fidelity simulations},
pages = {1-16},
doi = {10.33737/jgpps/133116},
journal = {Journal of the Global Power and Propulsion Society},
abstract = {Unsteady simulations of various components of a gas-turbine engine are often carried out independently and only share averaged quantities at the component interfaces. In order to study the impact and interactions between components, this work compares results from sectoral stand-alone simulations of a fan, compressor and annular combustion chamber of the DGEN-380 demonstrator engine at take-off conditions against an integrated 360 azimuthal degrees large-eddy simulation with over 2.1 billion cells of all previously listed components. Note that, at take-off conditions the compressor works at transonic conditions and generates an upstream-propagating shock that interacts with the fan modifying the shape of its wake with respect to the stand-alone simulation. Furthermore, the shock is seen as a tone in the pressure spectra at half the impeller blade passing frequency in the forward region of the engine. In the aft region, time-averaged fields are overall similar between stand-alone and integrated simulations but show a deviation in the azimuthal position of the hot-spot at the exit of the combustion chamber due to the addition of the diffuser. Pressure fluctuations generated in the compressor are captured in the combustion chamber as tones in the temperature and pressure spectra at the impeller blade-passing frequency and harmonics as well as an increase in the root-mean-square pressure.},
keywords = {interaction, LES, compressor, combustion chamber, fan, gas-turbine engine},
pdf = {https://cerfacs.fr/wp-content/uploads/2021/05/CFD_Perez-Arroyo_Towards-the-Large_Eddy-part2_J.gpps_.global21-69..pdf}}

Harnieh, M., Thomas, M., Bizzari, R., Dombard, J., Duchaine, F. and Gicquel, L.Y.M. (2020) Assessment of a coolant injection model on cooled high-pressure vanes with Large-Eddy Simulation, Flow Turbulence and Combustion, 104 (1) , pp. 643–672, doi: 10.1007/s10494-019-00091-3

[bibtex]

@ARTICLE{AR-CFD-20-23,
author = {Harnieh, M. and Thomas, M. and Bizzari, R. and Dombard, J. and Duchaine, F. and Gicquel, L.Y.M. },
title = {Assessment of a coolant injection model on cooled high-pressure vanes with Large-Eddy Simulation},
year = {2020},
number = {1},
volume = {104},
pages = {643–672},
doi = {10.1007/s10494-019-00091-3},
journal = {Flow Turbulence and Combustion},
abstract = {The high-pressure turbine blades are the components of the aero-engines which are the most exposed to extreme thermal conditions. To alleviate this issue, the blades are equipped with cooling systems to ensure long-term operation. However, the accurate prediction of the blade temperature and the design of the cooling system in an industrial context still remains a major challenge. Potential improvement is foreseen with Large-Eddy Simulation (LES) which is well suited to predict turbulent flows in such complex systems. Nonetheless, performing LES of a real cooled high-pressure turbine still remains expensive. To alleviate the issues of CPU cost, a cooling model recently developed in the context of combustion chamber liners is assessed in the context of blade cooling. This model was initially designed to mimic coolant jets injected at the wall surface and does not require to mesh the cooling pipes leading to a significant reduction in the CPU cost. The applicability of the mod
el is here evaluated on the cooled Nozzle Guide Vanes (NGV) of the Full Aerothermal Combustor Turbine interactiOns Research (FACTOR) test rig. To do so, a hole modeled LES using the cooling model is compared to a hole meshed LES. Results show that both simulations yield very similar results confirming the capability of the approach to predict the adiabatic film effectiveness. Advanced post-processing and analyses of the coolant mass fraction profiles show that the turbulent mixing between the coolant and hot flows is however reduced with the model. This finding is confirmed by the turbulent map levels which are lower in the modeled approach. Potential improvements are hence proposed to increase the accuracy of such methods.},
keywords = {Large-eddy simulation, Turbomachinery, Film cooling, Modelling}}

de Laborderie, J., Duchaine, F., Gicquel, L.Y.M. and Moreau, S. (2020) Wall-modeled Large-Eddy Simulations of a Multistage High-Pressure Compressor, Flow Turbulence and Combustion, 104, pp. 725–751, doi: 10.1007/s10494-019-00094-0

[bibtex]
[url]

@ARTICLE{AR-CFD-20-24,
author = {de Laborderie, J. and Duchaine, F. and Gicquel, L.Y.M. and Moreau, S. },
title = {Wall-modeled Large-Eddy Simulations of a Multistage High-Pressure Compressor},
year = {2020},
volume = {104},
pages = {725–751},
doi = {10.1007/s10494-019-00094-0},
journal = {Flow Turbulence and Combustion},
abstract = {This study aims at evaluating the feasibility and the accuracy of a Wall-Modeled Large Eddy Simulation of an actual aeronautical multistage axial high-pressure compressor. The computational domain is composed of 37 blades and a geometrically complex recirculating cavity. The numerical method TurboAVBP is able to handle such a technical challenge thanks to its unstructured and massively parallel approach as well as dedicated rotor-stator interface treatments. The influence of grid resolution, from less than 100 millions to more than 1 billion of cells, is particularly evaluated. The intermediate grid correctly predicts the global aerodynamic performances up to the lowest mass flow rate regime. In comparing with time-resolved measurements, the finest grid is shown to accurately predict flow within rotors, especially in their tip regions that are critical for performances and stability of the whole compressor.},
url = {https://link.springer.com/article/10.1007/s10494-019-00094-0}}

Esnault, S., Duchaine, F., Gicquel, L.Y.M. and Moreau, S. (2020) Large Eddy Simulation of heat transfer within a multi-perforation synthetic jets configuration, Journal of Turbomachinery, 142 (6) , pp. 061010, doi: 10.1115/1.4046545

[bibtex]

@ARTICLE{AR-CFD-20-33,
author = {Esnault, S. and Duchaine, F. and Gicquel, L.Y.M. and Moreau, S. },
title = {Large Eddy Simulation of heat transfer within a multi-perforation synthetic jets configuration},
year = {2020},
number = {6},
volume = {142},
pages = {061010},
doi = {10.1115/1.4046545},
journal = {Journal of Turbomachinery},
abstract = {Synthetic jets are produced by devices that enable a suction phase followed by an ejection phase. The resulting
mean mass budget is hence null and no addition of mass in the system is required. These particular jets have
especially been considered for some years for flow control applications. They also display features that can become
of interest to enhance heat exchanges, for example for wall cooling issues. Synthetic jets can be generated through
different mechanisms, such as acoustics by making use of a Helmholtz resonator or through the motion of a piston as
in an experience mounted at Institut Pprime in France. The objective of this specific experiment is to understand how
synthetic jets can enhance heat transfer in a multi-perforated configuration. As a complement to this experimental
set up, Large-Eddy Simulations are produced and analysed in the present document to investigate the flow behavior
as well as the impact of the synthetic jets on wall heat transfer.
The experimental system considered here consists in a perforated heated plate, each perforation being above a
cavity where a piston is used to control the synthetic jets. Placed in a wind tunnel test section, the device can be
studied with a grazing flow and multiple operating points are available. The one considered here implies a grazing
flow velocity of 12.8 m.s-1, corresponding to a Mach number around 0.04, and a piston displacement of 22 mm
peak-to-peak at a frequency of 12.8 Hz. These two latter parameters lead to a jet Reynolds number of about 830.
A good agreement is found between numerical results and experimental data. The simulations are then used
to provide a detailed understanding of the flow. Two main behaviours are found, depending on the considered midperiod.
During the ejection phase, the flow transitions to turbulence and the formation of characteristic structures is observed; the plate is efficiently cooled. During the suction phase the main flow is stabilised; the heat enhancement
is particularly efficient in the hole wakes but not between them, leading to a heterogeneous temperature field.},
keywords = {Boundary layer development, Computational Fluid Dynamics (CFD), Heat transfer and film cooling}}

Duchaine, F., Gicquel, L.Y.M., Grosnickel, T. and Koupper, C. (2020) Large-Eddy Simulation of the Flow Developing in Static and Rotating Ribbed Channels, Journal of Turbomachinery, 142 (4) , pp. 041003, doi: 10.1115/1.4046267

[bibtex]
[url]

@ARTICLE{AR-CFD-20-34,
author = {Duchaine, F. and Gicquel, L.Y.M. and Grosnickel, T. and Koupper, C. },
title = {Large-Eddy Simulation of the Flow Developing in Static and Rotating Ribbed Channels},
year = {2020},
number = {4},
volume = {142},
pages = {041003},
doi = {10.1115/1.4046267},
journal = {Journal of Turbomachinery},
abstract = {In the present work, the turbulent flow fields in a static and rotating ribbed channel representative of an aeronautical gas turbine are investigated by the means of wall-resolved compressible large-Eddy simulation (LES). This approach has been previously validated in a squared ribbed channel based on an experimental database from the Von Karman Institute (Reynolds and rotation numbers of about 15,000 and ±0.38, respectively). LES results prove to reproduce differences induced by buoyancy in the near rib region and resulting from adiabatic or anisothermal flows under rotation. The model also manages to predict the turbulence increase (decrease) around the rib in destabilizing (stabilizing) rotation of the ribbed channels. On this basis, this paper investigates in more detail the spatial development of the flow along the channel and its potential impact on secondary flow structures. More specifically and for all simulations, results of the adiabatic static case exhibit two contra-rotating structures that are close to the lateral walls of the channel induced by transversal pressure difference created by the ribs. These structures are generated after the first ribs and appear behind all inter-rib sections, their relative position is partly affected by rotation. When considering the stabilizing rotating case, two additional contra-rotating structures also develop along the channel from the entrance close to the low-pressure wall (rib-mounted side). These vortices are due to the confinement of the configuration, inflow profile and are the result of Coriolis forces induced by rotation. Görtler vortices also appear on the pressure wall (opposite to the rib-mounted side). In the destabilizing rotating case, these two types of secondary structures are found to co-exist, and their migration in the channel is significantly different due to the presence of the ribs on the pressure side. Finally, it is shown that heat transfer affects only marginally the static and stabilized cases while it changes more significantly the flow organization in the destabilizing case mainly because of enhanced heat transfer and increased buoyancy force effects.},
keywords = {CFD, LES, HEAT TRANSFER AND FILM COOLING},
url = {https://asmedigitalcollection.asme.org/turbomachinery/article/142/4/041003/1074326/Large-Eddy-Simulation-of-the-Flow-Developing-in}}

Dupuy, D., Gicquel, L.Y.M., Odier, N., Duchaine, F. and Arts, T. (2020) Analysis of the effect of intermittency in a high-pressure turbine blade, Physics of Fluids, 32 (9) , pp. 095101, doi: 10.1063/5.0018679

[bibtex]

@ARTICLE{AR-CFD-20-94,
author = {Dupuy, D. and Gicquel, L.Y.M. and Odier, N. and Duchaine, F. and Arts, T. },
title = {Analysis of the effect of intermittency in a high-pressure turbine blade},
year = {2020},
number = {9},
volume = {32},
pages = {095101},
doi = {10.1063/5.0018679},
journal = {Physics of Fluids},
abstract = {High-pressure turbine blades are subject to large thermomechanical loads that may threaten their mechanical integrity. The prediction of the heat transfer on the blade surface, crucial to ensure its durability, thus requires an accurate description of the flow physics around the blade to be reliable. In an effort to better qualify the use of computational fluid dynamics in this design context as well as the need for an improved understanding of the flow physics, this paper investigates a transonic highly loaded linear turbine blade cascade that has been found difficult to predict in the literature using large-eddy simulations. Indeed, the configuration results in shocks and acoustic waves on the suction side of the blade, features that are commonly encountered in high-pressure turbines. Turbulent spots are observed on the suction-side boundary layer with an inlet turbulence intensity of 6%. The turbulent spots are shown to have a complex and highly unsteady effect on the shock/boundary-layer interaction, disrupting flow detachment and creating laminar spots downstream of the shock. To address these transient flow phenomena, conditional averages based on the intermittency level are introduced to show that accurate heat transfer predictions require an accurate prediction of the rate of turbulent-spot production. The analysis then focuses on the effect of intermittency on the turbulent kinetic energy exchanges in the near-wall region as the turbulent kinetic energy balance must be addressed in Reynolds-averaged Navier–Stokes models.},
keywords = {Navier-Stokes, turbulence, CFD}}

Laurent, C., Esclapez, L., Maestro, D., Staffelbach, G., Cuenot, B., Selle, L., Schmitt, T., Duchaine, F. and Poinsot, T. (2019) Flame-wall interaction effects on the flame root stabilization mechanisms of a doubly-transcritical LO2/LCH4 cryogenic flame, Proceedings of the Combustion Institute, 37 (4) , pp. 5147-5154, doi: 10.1016/j.proci.2018.05.105

[bibtex]
[url]

@ARTICLE{AR-CFD-19-30,
author = {Laurent, C. and Esclapez, L. and Maestro, D. and Staffelbach, G. and Cuenot, B. and Selle, L. and Schmitt, T. and Duchaine, F. and Poinsot, T. },
title = {Flame-wall interaction effects on the flame root stabilization mechanisms of a doubly-transcritical LO2/LCH4 cryogenic flame},
year = {2019},
number = {4},
volume = {37},
pages = { 5147-5154},
doi = {10.1016/j.proci.2018.05.105},
journal = {Proceedings of the Combustion Institute},
abstract = {High-fidelity numerical simulations are used to study flame root stabilization mechanisms of cryogenic flames, where both reactants (O2 and CH4 ) are injected in transcritical conditions in the geometry of the laboratory scale test rig Mascotte operated by ONERA (France). Simulations provide a detailed insight into flame root stabilization mechanisms for these diffusion flames: they show that the large wall heat losses at the lips of the coaxial injector are of primary importance, and require to solve for the fully coupled conjugate heat transfer problem. In order to account for flameâ€“wall interaction (FWI) at the injector lip, detailed chemistry effects are also prevalent and a detailed kinetic mechanism for CH4 oxycombustion at high pressure is derived and validated. This kinetic scheme is used in a real-gas fluid solver, coupled with a solid thermal solver in the splitter plate to calculate the unsteady temperature field in the lip. A simulation with adiabatic boundary
conditions, an hypothesis that is often used in real-gas combustion, is also performed for comparison. It is found that adiabatic walls simulations lead to enhanced cryogenic reactants vaporization and mixing, and to a quasi-steady flame, which anchors within the oxidizer stream. On the other hand, FWI simulations produce
self-sustained oscillations of both lip temperature and flame root location at similar frequencies: the flame root moves from the CH 4 to the O 2 streams at approximately 450 Hz, affecting the whole flame structure.},
keywords = {Cryogenic flame, Flame–wall interaction, Conjugate heat transfer, Real-gas thermodynamics, Flame anchoring},
url = {https://www.sciencedirect.com/science/article/pii/S1540748918301068}}

Pérez-Arroyo, C., Léonard, T., Sanjosé, M., Moreau, S. and Duchaine, F. (2019) Large Eddy Simulation of a scale-model turbofan for fan noise source diagnostic, Journal of Sound and Vibration, 445, pp. 64-76 , doi: 10.1016/j.jsv.2019.01.005

[bibtex]
[url]

@ARTICLE{AR-CFD-19-242,
author = {Pérez-Arroyo, C. and Léonard, T. and Sanjosé, M. and Moreau, S. and Duchaine, F. },
title = {Large Eddy Simulation of a scale-model turbofan for fan noise source diagnostic},
year = {2019},
number = {april},
volume = {445},
pages = { 64-76 },
doi = {10.1016/j.jsv.2019.01.005},
journal = {Journal of Sound and Vibration},
abstract = {A wall-modeled statistically converged Large Eddy Simulation (LES) of the
turbulent flow in the NASA Source Diagnostic Test turbofan has been successfully performed for the first time. A good agreement with aerodynamic
measurements is observed for both Reynolds Averaged Navier-Stokes and
LES results, although the LES provides better results in the tip regions
where large coherent structures appear and no flow separation on the stator
vanes is observed. In the LES the boundary layer naturally transition to turbulence on the blade suction side but remains quasi laminar over most of its
pressure side. The rotor-wake turbulence yielding the stage broadband noise
is then seen to be quasi isotropic. Transition on the downstream stator vanes
is not triggered by the wake impingement but rather occurs at mid-chord.
Finally, acoustics are investigated using both Ffowcs Williams & Hawkings’
and Goldstein’s analogies from the recorded LES noise source on the stator
vanes. The latter analogy provides levels closer to the measurements especially at high frequencies, although the results are most likely still influenced
by too coherent rotor tip secondary flow at low frequencies.},
url = {https://doi.org/10.1016/j.jsv.2019.01.005}}

Mejia, D., Brebion, M., Ghani, A., Kaiser, E., Duchaine, F., Selle, L. and Poinsot, T. (2018) Influence of flame-holder temperature on the acoustic flame transfer functions of a laminar flame, Combustion and Flame, 188, pp. 5-12, doi: 10.1016/j.combustflame.2017.09.016

[bibtex]

@ARTICLE{AR-CFD-18-22,
author = {Mejia, D. and Brebion, M. and Ghani, A. and Kaiser, E. and Duchaine, F. and Selle, L. and Poinsot, T. },
title = {Influence of flame-holder temperature on the acoustic flame transfer functions of a laminar flame},
year = {2018},
number = {février},
volume = {188},
pages = {5-12},
doi = {10.1016/j.combustflame.2017.09.016},
journal = {Combustion and Flame},
abstract = {The occurrence of combustion instabilities in high-performance engines such as gas turbines is often affected by the thermal state of the engine. For example, strong bursts of pressure fluctuations may occur at cold start for operating conditions that are stable once the engine reaches thermal equilibrium. This observation raises the question of the influence of material temperature on the response of flames to acoustic perturbations. In this study, we assess the influence of the temperature of the flame holder for a laminar flame. Both experiments and numerical simulations show that the Flame Transfer Function (FTF) is strongly affected by the flame-holder temperature. The key factors driving the evolution of the FTF are the flame-root location as well as the modification of the flow, which affects its stability. In the case of the cooled flame-holder, the formation of a recirculation zone is identified as the main impact on the FTF.},
keywords = {DNS , Conjugate heat transfer, Analytically reduced chemistry, Flame transfer function , Premixed ﬂame, Laminar ﬂame}}

Berger, S., Duchaine, F. and Gicquel, L.Y.M. (2018) Bluff-body Thermal Property and Initial State Effects on a Laminar Premixed Flame Anchoring Pattern, Flow Turbulence and Combustion, 100 (2) , pp. 561–591, doi: 10.1007/s10494-017-9841-y

[bibtex]

@ARTICLE{AR-CFD-18-149,
author = {Berger, S. and Duchaine, F. and Gicquel, L.Y.M. },
title = {Bluff-body Thermal Property and Initial State Effects on a Laminar Premixed Flame Anchoring Pattern},
year = {2018},
number = {2},
volume = {100},
pages = {561–591},
doi = {10.1007/s10494-017-9841-y},
journal = {Flow Turbulence and Combustion},
abstract = {Bluff-body stabilized laminar flames remain at the root of many industrial applications. Such a simple flame arrangement although steady results from complex chemical, flow mixing as well as solid body thermal interactions that are still today misunderstood. Numerically, accurate predictions of such non linear problems require Conjugate Heat Transfer (CHT) approaches that are seldom because of the need for complex fluid flow solvers as well as multi-physics coupling strategies that are computationally expensive and difficult to master. Such numerical tools however provide access to fundamental elements otherwise inaccessible. Relying on Direct Numerical Simulation (DNS) CHT based predictions, the following work underlines several key features of importance to predict and understand square bluff-body stabilized flames. In the case of fluid only predictions, where the bluff-body wall temperature is fixed and assumed constant, three possible flame topologies are obtained and respectively qualified as anchored, lifted and bowed flames. Out of these three stable flow solutions, only two topologies are found physically possible whenever computed in a CHT context. Furthermore, depending on the solid material and the initial solution, the non linear CHT problem exhibits multiple solutions highlighting the complex coupling that can arise. As evidenced by these simple flame problems, such a behavior higlights the potential difficulties of predicting flame wall interaction problems where coupling schemes and turbulent closures / modeling will be required.},
keywords = {LES, Heat transfer, Reacting flow, CHT, Coupling scheme and Convergence }}

de Laborderie, J., Duchaine, F., Gicquel, L.Y.M., Vermorel, O., Wang, G. and Moreau, S. (2018) Numerical analysis of a high-order unstructured overset grid method for compressible LES of turbomachinery, Journal of Computational Physics, 363, pp. 371–398, doi: 10.1016/j.jcp.2018.02.045

[bibtex]
[url]

@ARTICLE{AR-CFD-18-46,
author = {de Laborderie, J. and Duchaine, F. and Gicquel, L.Y.M. and Vermorel, O. and Wang, G. and Moreau, S. },
title = {Numerical analysis of a high-order unstructured overset grid method for compressible LES of turbomachinery},
year = {2018},
number = {June},
volume = {363},
pages = {371–398},
doi = {10.1016/j.jcp.2018.02.045},
journal = {Journal of Computational Physics},
abstract = {Large-Eddy Simulation (LES) is recognized as a promising method for high-fidelity flow predictions in turbomachinery applications. The presented approach consists of the coupling of several instances of the same LES unstructured solver through an overset grid method. A high-order interpolation, implemented within this coupling method, is introduced and evaluated on several test cases. It is shown to be third order accurate, to preserve the accuracy of various second and third order convective schemes and to ensure the continuity of diffusive fluxes and subgrid scale tensors even in detrimental interface configurations. In this analysis, three types of spurious waves generated at the interface are identified. They are significantly reduced by the high-order interpolation at the interface. The latter having the same cost as the original lower order method, the high-order overset grid method appears as a promising alternative to be used in all the applications.},
keywords = {comb},
url = {https://doi.org/10.1016/j.jcp.2018.02.045}}

Bizzari, R., Lahbib, D., Dauptain, A., Duchaine, F., Gicquel, L.Y.M. and Nicoud, F. (2018) A Thickened-Hole Model for Large Eddy Simulations over Multiperforated Liners, Flow Turbulence and Combustion, 101 (3) , pp. 705-717, doi: 10.1007/s10494-018-9909-3

[bibtex]
[url]

@ARTICLE{AR-CFD-18-50,
author = {Bizzari, R. and Lahbib, D. and Dauptain, A. and Duchaine, F. and Gicquel, L.Y.M. and Nicoud, F. },
title = {A Thickened-Hole Model for Large Eddy Simulations over Multiperforated Liners},
year = {2018},
number = {3},
volume = {101},
pages = {705-717},
doi = {10.1007/s10494-018-9909-3},
journal = {Flow Turbulence and Combustion},
abstract = {In aero-engines, mutiperforation cooling systems are often used to shield the combustor wall and ensure durability of the engine. Fresh air coming from the casing goes through thousands of angled perforations and forms a film which protects the liner. When performing Large Eddy Simulations (LES) of a real engine, the number of sub-millimetric holes is far too large to allow a complete and accurate description of each aperture. Homogeneous models allow to simulate multiperforated plates with a mesh size bigger than the hole but fail in representing the jet penetration and mixing. A heterogeneous approach is proposed in this study, where the apertures are thickened if necessary so that the jet-crossflow interaction is properly represented. Simulations using homogeneous and thickened-hole models are compared to a fully resolved computation for various grid resolutions in order to illustrate the potential of the method.},
keywords = {COMB, Aerodynamics, LES, Multiperforated plate, Modelling},
url = {https://doi.org/10.1007/s10494-018-9909-3}}

Bizzari, R., Lahbib, D., Dauptain, A., Duchaine, F., Richard, S. and Nicoud, F. (2018) Low order modeling method for assessing the temperature of multi-perforated plates, International Journal of Heat and Mass Transfer, 127, pp. 727–742, doi: 10.1016/j.ijheatmasstransfer.2018.07.059

[bibtex]
[url]

@ARTICLE{AR-CFD-18-116,
author = {Bizzari, R. and Lahbib, D. and Dauptain, A. and Duchaine, F. and Richard, S. and Nicoud, F. },
title = {Low order modeling method for assessing the temperature of multi-perforated plates},
year = {2018},
number = {Part B},
volume = {127},
pages = {727–742},
doi = {10.1016/j.ijheatmasstransfer.2018.07.059},
journal = {International Journal of Heat and Mass Transfer},
abstract = {A low-order model is proposed to predict the temperature of a multi-perforated plate from an unresolved adiabatic computation. Its development relies on the analysis of both an adiabatic and a conjugate heat transfer wall resolved large eddy simulation of an academic multi-perforated liner representative of the cooling systems used in combustion chambers of actual aero-engines. These two simulations show that the time averaged velocity field is marginally modified by the coupling with the heat diffusion in the perforated plate when compared to the adiabatic case. This gives rise to a methodology to assess the wall temperature from an unresolved adiabatic computation. It relies on heat transfer coefficients from referenced correlations as well as a mixing temperature relevant to the flow in the injection region where the cold micro-jets mix with the hot outer flow. In this approach, a coarse mesh simulation using an homogeneous adiabatic model for the aerodynamics of the flow with effusion is post-processed to provide a low cost alternative to conjugate heat transfer computations based on hole resolved meshes. The model is validated on an academic test case and successfully applied to a real industrial combustion chamber.},
keywords = {Effusion cooling, Conjugate heat transfer, Large-Eddy simulations, Adiabatic computations, Coupled computation, Modeling},
url = {https://doi.org/10.1016/j.ijheatmasstransfer.2018.07.059}}

Boulet, L., Bénard, P., Lartigue, G., Moureau, V., Didorally, S., Chauvet, N. and Duchaine, F. (2018) Modeling of Conjugate Heat Transfer in a Kerosene/Air Spray Flame used for Aeronautical Fire Resistance Tests, Flow Turbulence and Combustion, 101 (2) , pp. 579–602

[bibtex]
[url]

@ARTICLE{AR-CFD-18-120,
author = {Boulet, L. and Bénard, P. and Lartigue, G. and Moureau, V. and Didorally, S. and Chauvet, N. and Duchaine, F. },
title = {Modeling of Conjugate Heat Transfer in a Kerosene/Air Spray Flame used for Aeronautical Fire Resistance Tests},
year = {2018},
number = {2},
volume = {101},
pages = {579–602},
journal = {Flow Turbulence and Combustion},
abstract = {Airworthiness standards require a fire resistance demonstration for aircraft or helicopter engines to obtain a type certificate. This demonstration relies on tests performed with prototype engine parts in the late stages of the development. In hardest tests, a kerosene standardized flame with imposed burnt gas temperature and heat flux is placed next to the engine casing during a given time. The aim of this work is to provide a better characterization of a kerosene/air certification burner in order to reach a better understanding of the thermal environment during fire tests. To this purpose, Large-Eddy Simulation (LES) of the certification burner is carried out. Spray combustion, forced convection on walls and conduction in the solid parts of the burner are coupled to achieve a detailed description of heat transfer. In a first place, physical aspects involved inside the burner in an adiabatic case are described. Then, differences that exist with a conjugate convective and conductive heat transfer case are analyzed. To a larger extent, the aim is to have a better characterization of the flow impinging the casing and to progress on fire test modeling so as to minimize the risks of test failure.},
keywords = {LES, TURBULENT COMBUSTION, Lagrangian particles },
url = {https://doi.org/10.1007/s10494-018-9965-8}}

Odier, N., Sanjosé, M., Gicquel, L.Y.M., Poinsot, T., Moreau, S. and Duchaine, F. (2018) A characteristic inlet boundary condition for compressible, turbulent, multispecies turbomachinery flows, Computers and Fluids, 178, pp. 41-55, doi: 10.1016/j.compfluid.2018.09.014

[bibtex]
[url]

@ARTICLE{AR-CFD-18-184,
author = {Odier, N. and Sanjosé, M. and Gicquel, L.Y.M. and Poinsot, T. and Moreau, S. and Duchaine, F. },
title = {A characteristic inlet boundary condition for compressible, turbulent, multispecies turbomachinery flows},
year = {2018},
volume = {178},
pages = {41-55},
doi = {10.1016/j.compfluid.2018.09.014},
journal = {Computers and Fluids},
abstract = {A methodology to implement non-reflecting boundary conditions for turbomachinery
applications, based on characteristic analysis is described in this paper.
For these simulations, inlet conditions usually correspond to imposed total pressure,
total temperature, flow angles and species composition. While directly
imposing these quantities on the inlet boundary condition works correctly for
steady RANS simulations, this approach is not adapted for compressible unsteady
Large Eddy Simulations because it is fully reflecting in terms of acoustics.
Deriving non-reflecting conditions in this situation requires to construct
characteristic relations for the incoming wave amplitudes. These relations must
impose total pressure, total temperature, flow angle and species composition,
and simultaneously identify acoustic waves reaching the inlet to let them propagate
without reflection. This treatment must also be compatible with the
injection of turbulence at the inlet. The proposed approach shows how characteristic
equations can be derived to satisfy all these criteria. It is tested on
several cases, ranging from a simple inviscid 2D duct to a rotor/stator stage
with turbulence injection.},
keywords = {Characteristic inlet boundary condition, turbomachinery inflow conditions, compressible flow, turbulence injection, acoustic reflectivity},
url = {https://doi.org/10.1016/j.compfluid.2018.09.014}}

Duchaine, F., Dombard, J., Gicquel, L.Y.M. and Koupper, C. (2017) On the importance of inlet boundary conditions for aerothermal predictions of turbine stages with Large Eddy Simulation, Computers and Fluids, 154, pp. 60-73, doi: 10.1016/j.compfluid.2017.05.024

[bibtex]
[url]

@ARTICLE{AR-CFD-17-89,
author = {Duchaine, F. and Dombard, J. and Gicquel, L.Y.M. and Koupper, C. },
title = {On the importance of inlet boundary conditions for aerothermal predictions of turbine stages with Large Eddy Simulation},
year = {2017},
number = {September},
volume = {154},
pages = {60-73},
doi = {10.1016/j.compfluid.2017.05.024},
journal = {Computers and Fluids},
abstract = {The analysis of a combustion chamber effects on the aerodynamics and thermal loads applied on a turbine stage is proposed. To do so, an integrated wall-modeled Large-Eddy Simulation of a combustion chamber simulator along with its high pressure turbine stage is performed and compared to a standalone turbine stage computation operated under the same mean conditions. For the standalone stage simulations, a parametric study of the turbulence injected at the turbine stage inlet is also discussed. For this specific configuration and with the mesh resolution used, results illustrate that the aerodynamic expansion of the turbine stage is almost insensitive to the inlet turbulent conditions. However, the temperature distribution in the turbine passages as well as on the stator and rotor walls are highly impacted by these inlet conditions underlying the importance of inlet conditions in turbine stage computations and the potential of integrated combustion chamber/turbine simulations in such a context.},
url = {https://doi.org/10.1016/j.compfluid.2017.05.024}}

Aillaud, P., Gicquel, L.Y.M. and Duchaine, F. (2017) Investigation of the concave curvature effect for an impinging jet flow, Physical Review Fluids, 2 (11) , pp. 114608 - 34 pages, doi: 10.1103/PhysRevFluids.2.114608

[bibtex]

@ARTICLE{AR-CFD-17-275,
author = {Aillaud, P. and Gicquel, L.Y.M. and Duchaine, F. },
title = {Investigation of the concave curvature effect for an impinging jet flow},
year = {2017},
number = {11},
volume = {2},
pages = {114608 - 34 pages},
doi = {10.1103/PhysRevFluids.2.114608},
journal = {Physical Review Fluids},
abstract = {The concave curvature effect for an impinging jet flow is discussed in this paper. To do so, a submerged axisymmetric isothermal impinging jet at a Reynolds number (based on the nozzle diameter and the bulk velocity at the nozzle outlet) Re=23000 and for a nozzle to plate distance of two jet diameters H=2D is considered. This investigation is done numerically using a wall-resolved large-eddy simulation. Two geometrical arrangements are studied. These correspond to a jet impinging on a flat plate and a jet impinging on a hemispherical concave plate with a relative curvature D/d=0.089, where d is the concave plate diameter. A detailed comparison shows that both flow configurations are very similar in terms of flow dynamics and heat transfer behaviors. The same mechanisms, coming from the initial jet instability and driving the heat transfer at the wall, are found for both geometries. However, a reduction of the mean wall heat transfer is reported for the jet impinging on the concave surface when compared to the flat plate impingement. This reduction mainly comes from the alleviation of the secondary peak. The deterioration of wall heat transfer is shown to be caused by a reduction in the intensity of the intermittent cold fluid injections generated by the secondary structures. These weaker events are assumed to be the consequence of the stabilizing normal pressure gradient, in the outer layer of the wall jet, induced by the concave curvature of the plate. This result goes against the current consensus, inherited from boundary layer studies, that is to say, that concave curvature enhances the heat transfer rate at the wall due to the formation of Görtler vortices. In an attempt to explain the contradictory result of the present study, a discussion is proposed in this paper showing that the commonly used analogy with boundary layer results must be made with care owing to several inherent differences between impinging jet and boundary layer flows.},
keywords = {AETHER, AVBP}}

Errera, M.-P. and Duchaine, F. (2016) Comparative study of coupling coefficients in Dirichlet-Robin precedure for fluid-structure aerothermal simulations, Journal of Computational Physics

[bibtex]
[url]

@ARTICLE{AR-CFD-16-29511,
author = {Errera, M.-P. and Duchaine, F. },
title = {Comparative study of coupling coefficients in Dirichlet-Robin precedure for fluid-structure aerothermal simulations},
year = {2016},
journal = {Journal of Computational Physics},
abstract = {This paper tests the performance of coupling coefficients of a Dirichlet–Robin transmission procedure in the context of steady conjugate heat transfer (CHT). Particular emphasis is put on the optimal coefficients highlighted recently in a theoretical study based on a normal mode stability analysis. This work can be seen as the logical continuation of that study in order to assess the relevance of the coefficients provided by the model problem in a realistic aerothermal computation. First, the numerical and physical CHT modeling methodologies are presented. Then, the optimal procedure applied to a Dirichlet–Robin algorithm (one-coefficient method) is briefly described. In order to gauge the ability of this model to predict the stability and convergence properties of a realistic case, it is compared to a heated cylinder in a flowfield test case. A series of 5 coupling coefficients and 3 Fourier numbers are considered. These parameters are introduced into the model problem as data to compute the amplification factor and the stability limits. The stability and convergence properties predicted by the model problem are then compared to those obtained in the CHT computation. This comparison shows an excellent overall agreement. Moreover, for all the Fourier numbers considered, the numerical solution is stable and oscillation-free when the optimal coefficient of the model problem is used. This would suggest that the one-dimensional normal mode analysis can provide relevant coefficients directly applicable to real CHT problems.},
url = {http://www.sciencedirect.com/science/article/pii/S0021999116000760}}

Papadogiannis, D., Duchaine, F., Gicquel, L.Y.M., Wang, G. and Moreau, S. (2016) Effects of Subgrid Scale Modeling on the Deterministic and Stochastic Turbulent Energetic Distribution in Large-Eddy Simulations of a High-Pressure Turbine Stage, Journal of Turbomachinery, 138 (9) , pp. 091005-091005-10

[bibtex]
[url]

@ARTICLE{AR-CFD-16-137,
author = {Papadogiannis, D. and Duchaine, F. and Gicquel, L.Y.M. and Wang, G. and Moreau, S. },
title = {Effects of Subgrid Scale Modeling on the Deterministic and Stochastic Turbulent Energetic Distribution in Large-Eddy Simulations of a High-Pressure Turbine Stage},
year = {2016},
number = {9},
volume = {138},
pages = {091005-091005-10},
journal = {Journal of Turbomachinery},
abstract = {This study focuses on the engine-representative MT1 transonic high-pressure turbine. Simulated by use of wall-modeled large-eddy simulations (LES) with three different subgrid scale (SGS) closures, mean pressure profiles across the blades as well as mean radial profiles at the rotor exit are found to be in good agreement with experimental data with only local differences between models. Unsteady flow features, inherently present in LES, are however affected by SGS modeling. This is evidenced by the relative energetic content of the deterministic to stochastic turbulent contributions evaluated, thanks to the triple decomposition analysis of the simulations. Origins of such differences are found to impact the entire radial distribution of the flow and activity, with deterministic and chaotic contributions distributed differently depending on the SGS model and reference frequency used to extract the deterministic signal. Such flow responses can be attributed to the different SGS capacities to satisfy basic turbulent flow features that translate in different dissipative and turbulent diffusive contributions of the three SGS models.},
url = {http://turbomachinery.asmedigitalcollection.asme.org/issue.aspx?journalid=135&issueid=935195&direction=P}}

Labarrère, L., Poinsot, T., Dauptain, A., Duchaine, F., Bellenoue, M. and Boust, B. (2016) Experimental and numerical study of cyclic variations in a Constant Volume Combustion chamber, Combustion and Flame, 172, pp. 49-61, ISSN 0010-2180, doi: 10.1016/j.combustflame.2016.06.027

[bibtex]

@ARTICLE{AR-CFD-16-167,
author = {Labarrère, L. and Poinsot, T. and Dauptain, A. and Duchaine, F. and Bellenoue, M. and Boust, B. },
title = {Experimental and numerical study of cyclic variations in a Constant Volume Combustion chamber},
year = {2016},
number = {October 2016},
volume = {172},
pages = {49-61},
issn = {0010-2180},
doi = {10.1016/j.combustflame.2016.06.027},
journal = {Combustion and Flame},
abstract = {This paper describes a joint experimental and numerical study of a Constant Volume Combustion (CVC) chamber for propulsion engines. Combustion takes place in a constant volume vessel where gases are injected from a pressurized air inlet using valves. They are ignited using a spark and exhaust through a second set of valves. Like piston engines, CVC combustion raises multiple questions linked to the volumetric efficiency of the valves, the heat losses to the chamber walls, the ignition in a strongly turbulent flow, the influence of residual gases. These issues can compromise the potential gains associated to constant volume combustion. They are investigated in an experimental setup and compared to a full compressible LES. The major conclusion is the existence of significant cyclic variations which are observed in the experiment and analyzed in the LES: the local flow velocity at spark timing and the level of residuals are the major factors leading to cyclic variations. Cycles also appear to be coupled: combustion during cycle N directly affects cycle (N+1), more than in a piston engine.},
keywords = {Turbulent flames}}

Mari, R., Cuenot, B., Rocchi, J.-Ph., Selle, L. and Duchaine, F. (2016) Effect of pressure on hydrogen / oxygen coupled flame–wall interaction, Combustion and Flame, 168, pp. 409-419, doi: 10.1016/j.combustflame.2016.01.004

[bibtex] [pdf]

@ARTICLE{AR-CFD-16-176,
author = {Mari, R. and Cuenot, B. and Rocchi, J.-Ph. and Selle, L. and Duchaine, F. },
title = {Effect of pressure on hydrogen / oxygen coupled flame–wall interaction},
year = {2016},
volume = {168},
pages = {409-419},
doi = {10.1016/j.combustflame.2016.01.004},
journal = {Combustion and Flame},
abstract = { The design and optimization of liquid-fuel rocket engines is a major scientific and technological challenge. One particularly critical issue is the heating of solid parts that are subjected to extremely high heat fluxes when exposed to the flame. This in turn changes the injector lip temperature, leading to possibly different flame behaviors and a fully coupled system. As the cham- ber pressure is usually much larger than the critical pressure of the mixture, supercritical flow behaviors add even more complexity to the thermal prob- lem. When simulating such phenomena, these thermodynamic conditions raise both modeling and numerical specific issues. In this paper, both sub- critical and supercritical Hydrogen/Oxygen one-dimensional, laminar flames interacting with solid walls are studied by use of conjugate heat transfer simulations, allowing to evaluate the wall heat flux and temperature, their impact on the flame as well as their sensitivity to high pressure and real gas thermodynamics up to 100 bar where real gas effects are important. At low pressure, results are found in good agreement with previous studies in terms of wall heat flux and quenching distance, and the wall stays close to isothermal. On the contrary, due to important changes of the fluid trans- port properties and the flame characteristics, the wall experiences significant heating at high pressure condition and the flame behavior is modified. },
keywords = {Real-gas, thermodynamics, Flame–wall interaction, Conjugate heat transfer},
pdf = {https://cerfacs.fr/wp-content/uploads/2017/01/CFD_Mari_15676.pdf}}

Koupper, C., Gicquel, L.Y.M., Duchaine, F., Bacci, T., Facchini, B., Picchi, A., Tarchi, L. and Bonneau, G. (2016) Experimental and Numerical Calculation of Turbulent Timescales at the Exit of an Engine Representative Combustor Simulator, Journal of Engineering for Gas Turbines and Power-Transactions of the ASME, 138 (2) , pp. 021503-021503-10.

[bibtex]
[url]

@ARTICLE{AR-CFD-16-178,
author = {Koupper, C. and Gicquel, L.Y.M. and Duchaine, F. and Bacci, T. and Facchini, B. and Picchi, A. and Tarchi, L. and Bonneau, G. },
title = {Experimental and Numerical Calculation of Turbulent Timescales at the Exit of an Engine Representative Combustor Simulator},
year = {2016},
number = {2},
volume = {138},
pages = {021503-021503-10.},
journal = {Journal of Engineering for Gas Turbines and Power-Transactions of the ASME},
abstract = {o deepen the knowledge of the interaction between modern lean burn combustors and high pressure (HP) turbines, a nonreactive real scale annular trisector combustor simulator (CS) has been assembled at University of Florence (UNIFI), with the goal of investigating and characterizing the combustor aerothermal field as well as the hot streak transport toward the HP vanes. To generate hot streaks and simulate lean burn combustor behaviors, the rig is equipped with axial swirlers fed by a main air flow stream that is heated up to 531 K, while liners with effusion cooling holes are fed by air at ambient temperature. Detailed experimental investigations are then performed with the aim of characterizing the turbulence quantities at the exit of the combustion module, and specifically evaluating an integral scale of turbulence. To do so, an automatic traverse system is mounted at the exit of the CS and equipped to perform hot wire anemometry (HWA) measurements. In this paper, two-point correlations are computed from the time signal of the axial velocity giving access to an evaluation of the turbulence timescales at each measurement point. For assessment of the advanced numerical method that is large Eddy simulation (LES), the same methodology is applied to a LES prediction of the CS. Although comparisons seem relevant and easily accessible, both approaches and contexts have fundamental differences: mostly in terms of duration of the signals acquired experimentally and numerically but also with potentially different acquisition frequencies. In the exercise that aims at comparing high-order statistics and diagnostics, the specificity of comparing experimental and numerical results is comprehensively discussed. Attention is given to the importance of the acquisition frequency, intrinsic bias of having a short duration signal and influence of the investigating windows. For an adequate evaluation of the turbulent time scales, it is found that comparing experiments and numerics for high Reynolds number flows inferring small-scale phenomena requires to obey a set of rules, otherwise important errors can be made. If adequately processed, LES and HWA are found to agree well indicating the potential of LES for such problems.},
url = {http://gasturbinespower.asmedigitalcollection.asme.org/article.aspx?articleID=2427501}}

Brebion, M., Mejia, D., Xavier, P., Duchaine, F., Bédat, B., Selle, L. and Poinsot, T. (2016) Joint experimental and numerical study of the influence of flame holder temperature on the stabilization of a laminar methane flame on a cylinder, Combustion and Flame, 172, pp. 153-161, ISSN 0010-2180 , doi: 10.1016/j.combustflame.2016.06.025

[bibtex]

@ARTICLE{AR-CFD-16-186,
author = {Brebion, M. and Mejia, D. and Xavier, P. and Duchaine, F. and Bédat, B. and Selle, L. and Poinsot, T. },
title = {Joint experimental and numerical study of the influence of flame holder temperature on the stabilization of a laminar methane flame on a cylinder},
year = {2016},
volume = {172},
pages = {153-161},
issn = {0010-2180 },
doi = {10.1016/j.combustflame.2016.06.025},
journal = {Combustion and Flame},
abstract = {The mechanisms controlling laminar flame anchoring on a cylindrical bluff-body are investigated using DNS and experiments. Two configurations are examined: water-cooled and uncooled steel cylinders. Comparisons between experimental measurements and DNS show good agreement for the flame root locations in the two configurations. In the cooled case, the flame holder is maintained at about 300 K and the flame is stabilized in the wake of the cylinder, in the recirculation zone formed by the products of combustion. In the uncooled case, the bluff-body reaches a steady temperature of about 700 K in both experiment and DNS and the flame is stabilized closer to it. The fully coupled DNS of the flame and the temperature field in the bluff-body also shows that capturing the correct radiative heat transfer from the bluff-body is a key ingredient to reproduce experimental results.},
keywords = {DNS, Conjugate heat transfer, Analytical chemistry, Radiative transfer, Stabilization, Premixed flame}}

Berger, S., Richard, S., Duchaine, F., Staffelbach, G. and Gicquel, L.Y.M. (2016) On the sensitivity of a helicopter combustor wall temperature to convective and radiative thermal loads, Applied Thermal Engineering, 103 (25) , pp. 1450-1459, ISSN 1359-4311, doi: 10.1016/j.applthermaleng.2016.04.054

[bibtex]
[url]

@ARTICLE{AR-CFD-16-187,
author = {Berger, S. and Richard, S. and Duchaine, F. and Staffelbach, G. and Gicquel, L.Y.M. },
title = {On the sensitivity of a helicopter combustor wall temperature to convective and radiative thermal loads},
year = {2016},
number = {25},
volume = {103},
pages = {1450-1459},
issn = {1359-4311},
doi = {10.1016/j.applthermaleng.2016.04.054},
journal = {Applied Thermal Engineering},
abstract = {The design of aeronautical engines is subject to many constraints that cover performance gain as well as increasingly sensitive environmental issues. These often contradicting objectives are currently being answered through an increase in the local and global temperature in the hot stages of the engine. As a result, hot spots could appear causing a premature aging of the combustion chamber. Today, the characterization of wall temperatures is performed experimentally by complex thermocolor tests in advanced phases of the design process. To limit such expensive experiments and integrate the knowledge of the thermal environment earlier in the design process, efforts are currently performed to provide high fidelity numerical tools able to predict the combustion chamber wall temperature including the main physical phenomena: combustion, convection and mixing of hot products and cold flows, radiative transfers as well as conduction in the solid parts. In this paper, partitioned coupling approaches based on a Large Eddy Simulation (LES) solver, a Discrete Ordinate Method radiation solver and an unsteady conduction code are used to investigate the sensitivity of an industrial combustor thermal environment to convection and radiation. Four computations including a reference adiabatic fluid only simulation, Conjugate Heat Transfer, Radiation-Fluid Thermal Interaction and fully coupled simulations are performed and compared with thermocolor experimental data. From the authors knowledge, such comparative study with LES has never been published. It is shown that coupling LES with conduction in walls is feasible in an industrial context with acceptable CPU costs and gives good trends of temperature repartition. Then, for the combustor geometry and operating point studied, computations illustrate that radiation plays an important role in the wall temperature distribution. Comparisons with thermocolor tests are globally in a better agreement when the three solvers are coupled.},
keywords = { Large Eddy Simulation, Conjugate Heat Transfer, Radiation, Combustion chamber},
url = {http://www.sciencedirect.com/science/article/pii/S1359431116305403}}

Wang, G., Sanjosé, M., Moreau, S., Papadogiannis, D., Duchaine, F. and Gicquel, L.Y.M. (2016) Noise mechanisms in a transonic high-pressure turbine stage, International Journal of Aeroacoustics, 15 (1-2) , pp. 144-161, doi: 10.1177/1475472X16630870

[bibtex]
[url]

@ARTICLE{AR-CFD-16-188,
author = {Wang, G. and Sanjosé, M. and Moreau, S. and Papadogiannis, D. and Duchaine, F. and Gicquel, L.Y.M. },
title = {Noise mechanisms in a transonic high-pressure turbine stage},
year = {2016},
number = {1-2},
volume = {15},
pages = {144-161},
doi = {10.1177/1475472X16630870 },
journal = {International Journal of Aeroacoustics},
abstract = { In modern ultra-high by-pass ratio turboengines, the noise contribution of both turbine stages and combustion chamber is expected to increase drastically. In the present work, both noise sources are evaluated in the realistic, fully three-dimensional transonic high-pressure turbine stage MT1 using large-eddy simulations (LES). An analysis of the basic flow field and the different turbine noise generation mechanisms is performed for two configurations: one with a steady inflow and one with an unsteady inflow, where a plane entropy wave train at a given frequency is injected at the inlet and propagates across the stage generating indirect noise. The noise is evaluated through Fourier analysis, dynamic mode decomposition of the flow field, and estimates of propagation coefficients. The steady case show three different dominant noise mechanisms: the usual stator wake brushing of the rotor blades, the several pulsating shocks in the stage and the vortex shedding. The forced results have additional tonal noise caused by the indirect noise mechanism generated by the acceleration and distortion of entropy spots. They are compared with previous two-dimensional (2D) simulations of a similar stator/rotor configuration, as well as with the compact theory. Results show that the upstream propagating entropy noise is reduced due to the choked turbine nozzle guide vane. Downstream acoustic waves are found to be of similar strength as the 2D case and larger than the blade passing frequency of the wake-interaction mechanism, highlighting the potential impact of indirect combustion noise on the overall noise signature of the engine.},
keywords = {Large Eddy Simulation},
url = {http://jae.sagepub.com/content/15/1-2/144}}

Aillaud, P., Duchaine, F., Gicquel, L.Y.M. and Didorally, S. (2016) Secondary peak in the Nusselt number distribution of impinging jet flows: A phenomenological analysis, Physics of Fluids, 28 (9) , pp. 095110-1- 095110-22, doi: 10.1063/1.4963687

[bibtex]

@ARTICLE{AR-CFD-16-211,
author = {Aillaud, P. and Duchaine, F. and Gicquel, L.Y.M. and Didorally, S. },
title = {Secondary peak in the Nusselt number distribution of impinging jet flows: A phenomenological analysis},
year = {2016},
number = {9},
volume = {28},
pages = {095110-1- 095110-22},
doi = {10.1063/1.4963687},
journal = {Physics of Fluids},
abstract = {This paper focuses on a wall-resolved Large Eddy Simulation (LES) of an isothermal round submerged air jet impinging on a heated flat plate, at a Reynolds number of 23 000 (based on the nozzle diameter and the bulk velocity at the nozzle outlet) and for a nozzle to plate distance of two jet diameters. This specific configuration is known to lead to a non-monotonic variation of the temporal-mean Nusselt number as a function of the jet center distance, with the presence of two distinct peaks located on the jet axis and close to two nozzle diameters from the jet axis. The objectives are here twofold: first, validate the LES results against experimental data available in the literature and second to explore this validated numerical database by use of high order statistics such as Skewness and probability density functions (PDF) of the temporal distribution of temperature and pressure to identify flow features at the origin of the second Nusselt peak. Skewness of the pressure temporal distribution reveals the rebound of the primary vortices located near the location of the secondary peak and allows to identify the initiation of the unsteady separation linked to the local minimum in the mean heat transfer distribution. In the region of mean heat transfer enhancement, joint velocity-temperature analyses highlight that the most probable event is a cold fluid flux towards the plate produced by the passage of the vortical structures. In parallel, heat transfer distributions, analyzed using similar statistical tools, allow to connect the above mentioned events to the heat transfer on the plate. Thanks to such advanced analyses the origin of the double peak is confirmed and connected to the flow dynamics.}}

Poubeau, A., Paoli, R., Dauptain, A., Duchaine, F. and Wang, G. (2015) Large-eddy simulations of a single-species solid rocket booster jet, AIAA Journal, 53, pp. 1467 - 1491

[bibtex]
[url]

@ARTICLE{AR-AE-15-20424,
author = {Poubeau, A. and Paoli, R. and Dauptain, A. and Duchaine, F. and Wang, G. },
title = {Large-eddy simulations of a single-species solid rocket booster jet},
year = {2015},
volume = {53},
pages = {1467 - 1491},
journal = {AIAA Journal},
url = {http://arc.aiaa.org/doi/abs/10.2514/1.J053361}}

Koupper, C., Gicquel, L.Y.M., Duchaine, F. and Bonneau, G. (2015) Advanced combustor exit plane temperature diagnostics based on large eddy simulations, Flow Turbulence and Combustion, 95 (1) , pp. 79 - 96

[bibtex]

@ARTICLE{AR-CFD-15-21119,
author = {Koupper, C. and Gicquel, L.Y.M. and Duchaine, F. and Bonneau, G. },
title = {Advanced combustor exit plane temperature diagnostics based on large eddy simulations},
year = {2015},
number = {1},
volume = {95},
pages = {79 - 96},
journal = {Flow Turbulence and Combustion}}

Léonard, T., Gicquel, L.Y.M., Gourdain, N. and Duchaine, F. (2015) Steady/unsteady Reynolds averaged navier-stokes and Large Eddy Simulations of turbine blade at high subsonic outlet mach number, Journal of Turbomachinery, 137 (4 ) , pp. 041001-1: 041001-10, doi: 10.1115/1.4028493

[bibtex] [pdf]

@ARTICLE{AR-CFD-15-21210,
author = {Léonard, T. and Gicquel, L.Y.M. and Gourdain, N. and Duchaine, F. },
title = {Steady/unsteady Reynolds averaged navier-stokes and Large Eddy Simulations of turbine blade at high subsonic outlet mach number},
year = {2015},
number = {4 },
volume = {137},
pages = {041001-1: 041001-10},
doi = {10.1115/1.4028493},
journal = {Journal of Turbomachinery},
abstract = {Reynolds-averaged Navier–Stokes (RANS), unsteady RANS (URANS), and large eddy
simulation (LES) numerical approaches are clear candidates for the understanding of
turbine blade flows. For such blades, the flow unsteady nature appears critical in certain
situations and URANS or LES should provide more physical understanding as illustrated
here for a laboratory high outlet subsonic Mach blade specifically designed to ease
numerical validation. Although RANS offers good estimates of the mean isentropic Mach
number and boundary layer thickness, LES and URANS are the only approaches
that reproduce the trailing edge flow. URANS predicts the mean trailing edge wake but
only LES offers a detailed view of the flow. Indeed, LESs identify flow phenomena
in agreement with the experiment, with sound waves emitted from the trailing edge separation
point that propagate upstream and interact with the lower blade suction side.
[DOI: 10.1115/1.4028493]},
pdf = {https://cerfacs.fr/wp-content/uploads/2017/02/CFD_LEONARD_turbo_137_2015.pdf}}

Koupper, C., Gicquel, L., Duchaine, F., Bacci, T., Facchini, B., Picchi, A., Tarchi, L. and Bonneau, G. (2015) Experimental and numerical calculation of turbulent timescales at the exit of an engine representative combustor simulator, Journal of Engineering for Gas Turbines and Power-Transactions of the ASME, 138 (2) , pp. 021503-021513

[bibtex]
[url]

@ARTICLE{AR-CFD-15-27744,
author = {Koupper, C. and Gicquel, L. and Duchaine, F. and Bacci, T. and Facchini, B. and Picchi, A. and Tarchi, L. and Bonneau, G. },
title = {Experimental and numerical calculation of turbulent timescales at the exit of an engine representative combustor simulator},
year = {2015},
number = {2},
volume = {138},
pages = {021503-021513},
journal = {Journal of Engineering for Gas Turbines and Power-Transactions of the ASME},
abstract = {To deepen the knowledge of the interaction between modern lean burn combustors and high pressure (HP) turbines, a nonreactive real scale annular trisector combustor simulator (CS) has been assembled at University of Florence (UNIFI), with the goal of investigating and characterizing the combustor aerothermal field as well as the hot streak transport toward the HP vanes. To generate hot streaks and simulate lean burn combustor behaviors, the rig is equipped with axial swirlers fed by a main air flow stream that is heated up to 531 K, while liners with effusion cooling holes are fed by air at ambient temperature. Detailed experimental investigations are then performed with the aim of characterizing the turbulence quantities at the exit of the combustion module, and specifically evaluating an integral scale of turbulence. To do so, an automatic traverse system is mounted at the exit of the CS and equipped to perform hot wire anemometry (HWA) measurements. In this paper, two-point correlations are computed from the time signal of the axial velocity giving access to an evaluation of the turbulence timescales at each measurement point. For assessment of the advanced numerical method that is large Eddy simulation (LES), the same methodology is applied to a LES prediction of the CS. Although comparisons seem relevant and easily accessible, both approaches and contexts have fundamental differences: mostly in terms of duration of the signals acquired experimentally and numerically but also with potentially different acquisition frequencies. In the exercise that aims at comparing high-order statistics and diagnostics, the specificity of comparing experimental and numerical results is comprehensively discussed. Attention is given to the importance of the acquisition frequency, intrinsic bias of having a short duration signal and influence of the investigating windows. For an adequate evaluation of the turbulent time scales, it is found that comparing experiments and numerics for high Reynolds number flows inferring small-scale phenomena requires to obey a set of rules, otherwise important errors can be made. If adequately processed, LES and HWA are found to agree well indicating the potential of LES for such problems.
},
url = {http://gasturbinespower.asmedigitalcollection.asme.org/article.aspx?articleID=2427501}}

Duchaine, F., Jauré, S., Poitou, D., Quémerais, E., Staffelbach, G., Morel, T. and Gicquel, L.Y.M. (2015) Analysis of High Performance Conjugate Heat Transfer with OpenPALM coupler, Computational Science and Discovery, 8 (1) , pp. 015003 , doi: 10.1088/1749-4699/8/1/015003

[bibtex] [pdf]

@ARTICLE{AR-CFD-15-27755,
author = {Duchaine, F. and Jauré, S. and Poitou, D. and Quémerais, E. and Staffelbach, G. and Morel, T. and Gicquel, L.Y.M. },
title = {Analysis of High Performance Conjugate Heat Transfer with OpenPALM coupler},
year = {2015},
number = {1},
volume = {8},
pages = {015003 },
doi = {10.1088/1749-4699/8/1/015003},
journal = {Computational Science and Discovery},
abstract = {In many communities such as climate science or industrial design, to solve complex coupled problems with high fidelity external coupling of legacy solvers puts a lot of pressure on the tool used for the coupling. The precision of such predictions not only largely depends on simulation resolutions and the use of huge meshes but also on high performance computing to reduce restitution times. In this context, the current work aims at studying the scalability of code coupling on high performance computing architectures for a conjugate heat transfer problem. The flow solver is a Large Eddy Simulation code that has been already ported on massively parallel architectures. The conduction solver is based on the same data structure and thus shares the flow solver scalability properties. Accurately coupling solvers on massively parallel architectures while maintaining their scalability is challenging. It requires exchanging and treating information based on two different computational grids that are partitioned differently on a different number of cores. Such transfers have to be thought to maintain code scalabilities while maintaining numerical accuracy. This raises communication and high performance computing issues: transferring data from a distributed interface to another distributed interface in a parallel way and on a very large number of processors is not straightforward and solutions are not clear. Performance tests have been carried out up to 12 288 cores on the CURIE supercomputer (TGCC/CEA). Results show a good behavior of the coupled model when increasing the number of cores thanks to the fully distributed exchange process implemented in the coupler. Advanced analyses are carried out to draw new paths for future developments for coupled simulations: i.e. optimization of the data transfer protocols through asynchronous communications or coupling-aware preprocessing of the coupled models (mesh partitioning phase).},
pdf = {https://cerfacs.fr/wp-content/uploads/2015/12/duchaine_computscdiscov.pdf}}

Papadogiannis, D., Duchaine, F., Gicquel, L., Wang, G., Moreau, S. and Nicoud, F. (2015) Assessment of the indirect combustion noise generated in a transonic high-pressure turbine stage, Journal of Engineering for Gas Turbines and Power-Transactions of the ASME, 138 (4) , pp. 0415030 (8 pp.), doi: 10.1115/1.4031404

[bibtex]
[url]

@ARTICLE{AR-CFD-15-27929,
author = {Papadogiannis, D. and Duchaine, F. and Gicquel, L. and Wang, G. and Moreau, S. and Nicoud, F. },
title = {Assessment of the indirect combustion noise generated in a transonic high-pressure turbine stage},
year = {2015},
number = {4},
volume = {138},
pages = {0415030 (8 pp.)},
doi = {10.1115/1.4031404},
journal = {Journal of Engineering for Gas Turbines and Power-Transactions of the ASME},
abstract = {Indirect combustion noise, generated by the acceleration and distortion of entropy waves through the turbine stages, has been shown to be the dominant noise source of gas turbines at low-frequencies and to impact the thermoacoustic behavior of the combustor. In the present work, indirect combustion noise generation is evaluated in the realistic, fully 3D transonic high-pressure turbine stage MT1 using large eddy simulations (LESs). An analysis of the basic flow and the different turbine noise generation mechanisms is performed for two configurations: one with a steady inflow and a second with a pulsed inlet, where a plane entropy wave train at a given frequency is injected before propagating across the stage generating indirect noise. The noise is evaluated through the dynamic mode decomposition (DMD) of the flow field. It is compared with the previous 2D simulations of a similar stator/rotor configuration, as well as with the compact theory of Cumpsty and Marble. Results show that the upstream propagating entropy noise is reduced due to the choked turbine nozzle guide vane. Downstream acoustic waves are found to be of similar strength to the 2D case, highlighting the potential impact of indirect combustion noise on the overall noise signature of the engine.},
url = {http://gasturbinespower.asmedigitalcollection.asme.org/article.aspx?articleid=2430876}}

Scholl, S., Verstraete, T., Torres-Garcia, J., Duchaine, F. and Gicquel, L.Y.M. (2015) Influence of the Thermal Boundary Conditions on the Heat Transfer of a Rib-Roughened Cooling Channel using LES, Proceedings of the Institution of Mechanical Engineers Part A-Journal of Power and Energy, 229 (5) , pp. 498-507, doi: 10.1177/0957650915591907

[bibtex]
[url]

@ARTICLE{AR-CFD-15-27932,
author = {Scholl, S. and Verstraete, T. and Torres-Garcia, J. and Duchaine, F. and Gicquel, L.Y.M. },
title = {Influence of the Thermal Boundary Conditions on the Heat Transfer of a Rib-Roughened Cooling Channel using LES},
year = {2015},
number = {5},
volume = {229},
pages = {498-507},
doi = { 10.1177/0957650915591907 },
journal = {Proceedings of the Institution of Mechanical Engineers Part A-Journal of Power and Energy},
abstract = {Internal cooling channels of turbine blades are rib-roughened to increase the heat transfer between the wall and the coolant. A large effort has been made in simulating these flows with large eddy simulations to have a better understanding of the flow physics. This contribution focuses on the thermal prediction capabilities of large eddy simulations for such cooling channels. Of particular interest to this study is the influence of the thermal boundary condition on the heat transfer coefficient. If important, this strongly indicates that conjugate effects exist that would need to be modeled resulting in significant additional computational cost. Studies were carried out for Reynolds numbers of 40,000 at different thermal uniform heat flux boundary conditions. The results are compared with experimental aerodynamic and thermal data obtained at the von Karman Institute for Fluid Dynamics. The main outcomes are: first, the results show the dependence of the heat transfer coefficient on the imposed thermal boundary condition, even though it is usually assumed in experimental and numerical studies to depend only on the aerodynamics; this assumption may not be valid. Second, the dependence of the heat transfer coefficient on the thermal boundary condition implies that conjugate heat transfer is important for the current configuration and can be captured numerically, although research on fully coupled, efficient large eddy simulations based conjugate heat transfer algorithms is still needed. },
url = {https://journals.sagepub.com/doi/10.1177/0957650915591907}}

Bonhomme, A., Duchaine, F., Wang, G., Selle, L. and Poinsot, Th. (2014) A parallel multidomain coupled strategy to compute turbulent flows in fan-stirred closed vessels, Computers and Fluids, 101, pp. 183 - 193

[bibtex]

@ARTICLE{AR-CFD-14-20603,
author = {Bonhomme, A. and Duchaine, F. and Wang, G. and Selle, L. and Poinsot, Th. },
title = {A parallel multidomain coupled strategy to compute turbulent flows in fan-stirred closed vessels},
year = {2014},
number = {September},
volume = {101},
pages = {183 - 193},
journal = {Computers and Fluids}}

Duchaine, F., Boileau, M., Sommerer, Y. and Poinsot, Th. (2014) Large Eddy Simulation of the flow and heat transfer around two square cylinders in a tandem arrangement, Journal of Heat Transfer, 136 (10)

[bibtex]

@ARTICLE{AR-CFD-14-20842,
author = {Duchaine, F. and Boileau, M. and Sommerer, Y. and Poinsot, Th. },
title = {Large Eddy Simulation of the flow and heat transfer around two square cylinders in a tandem arrangement},
year = {2014},
number = {10},
volume = {136},
journal = {Journal of Heat Transfer}}

Gourdain, N., Sicot, F., Duchaine, F. and Gicquel, L.Y.M. (2014) Large eddy simulation of flows in industrial compressors: a path from 2015 to 2035, Phil. Trans. R. Soc. A, 372 (20130323)

[bibtex]
[url]

@article{AR-CFD-14-21003,
author = {Gourdain, N. and Sicot, F. and Duchaine, F. and Gicquel, L.Y.M. },
title = {Large eddy simulation of flows in industrial compressors: a path from 2015 to 2035},
year = {2014},
number = {20130323},
volume = {372},
journal = {Phil. Trans. R. Soc. A},
url = {http://www.cerfacs.fr/~cfdbib/repository/TR_CFD_14_79.pdf}}

Koupper, C., Caciolli, G., Gicquel, L.Y.M., Duchaine, F., Bonneau, G., Tarchi, L. and Facchini, B. (2014) Development of an engine representative combustor simulator dedicated to hot streak generation, Journal of Turbomachinery, 136 (11)

[bibtex]

@ARTICLE{AR-CFD-14-21116,
author = {Koupper, C. and Caciolli, G. and Gicquel, L.Y.M. and Duchaine, F. and Bonneau, G. and Tarchi, L. and Facchini, B. },
title = {Development of an engine representative combustor simulator dedicated to hot streak generation},
year = {2014},
number = {11},
volume = {136},
journal = {Journal of Turbomachinery}}

Koupper, C., Poinsot, Th., Gicquel, L.Y.M. and Duchaine, F. (2014) Compatibility of characteristic boundary conditions with radial equilibrium in turbomachinery simulations, AIAA Journal, 52 (12) , pp. 2829 - 2839, ISSN 0001-1452 , doi: 10.2514/1.J052915

[bibtex]
[url]

@ARTICLE{AR-CFD-14-21117,
author = {Koupper, C. and Poinsot, Th. and Gicquel, L.Y.M. and Duchaine, F. },
title = {Compatibility of characteristic boundary conditions with radial equilibrium in turbomachinery simulations},
year = {2014},
number = {12},
volume = {52},
pages = {2829 - 2839},
issn = {0001-1452 },
doi = {10.2514/1.J052915},
journal = {AIAA Journal},
url = {http://arc.aiaa.org/doi/abs/10.2514/1.J052915}}

Lecocq, G., Poitou, D., Hernandez-Vera, I., Duchaine, F., Riber, E. and Cuenot, B. (2014) A methodology for soot prediction including thermal radiation in complex industrial burners, Flow Turbulence and Combustion, 92 (4) , pp. 947 - 970

[bibtex]

@ARTICLE{AR-CFD-14-21201,
author = {Lecocq, G. and Poitou, D. and Hernandez-Vera, I. and Duchaine, F. and Riber, E. and Cuenot, B. },
title = {A methodology for soot prediction including thermal radiation in complex industrial burners},
year = {2014},
number = {4},
volume = {92},
pages = {947 - 970},
journal = {Flow Turbulence and Combustion}}

Wang, G., Duchaine, F., Papadogiannis, D., Duran, I., Moreau, S. and Gicquel, L.Y.M. (2014) An overset grid method for large eddy simulation of turbomachinery stages, Journal of Computational Physics, 274, pp. 333 - 355

[bibtex]

@article{AR-CFD-14-21739,
author = {Wang, G. and Duchaine, F. and Papadogiannis, D. and Duran, I. and Moreau, S. and Gicquel, L.Y.M. },
title = {An overset grid method for large eddy simulation of turbomachinery stages},
year = {2014},
number = {October},
volume = {274},
pages = {333 - 355},
journal = {Journal of Computational Physics}}

Boileau, M., Duchaine, F., Jouhaud, J.-C. and Sommerer, Y. (2013) Large Eddy Simulation of heat transfer around a square cylinder using unstructured grids, AIAA Journal, 51 (2) , pp. 372 - 385

[bibtex]
[url]

@ARTICLE{AR-CFD-13-20600,
author = {Boileau, M. and Duchaine, F. and Jouhaud, J.-C. and Sommerer, Y. },
title = {Large Eddy Simulation of heat transfer around a square cylinder using unstructured grids},
year = {2013},
number = {2},
volume = {51},
pages = {372 - 385},
journal = {AIAA Journal},
abstract = {This paper presents a method of large-eddy simulation on unstructured grids designed to predict the wall heat transfer in typical aeronautical applications featuring turbulent flows and complex geometries. Two types of wall treatments are considered: a wall-function model using a full tetrahedral grid and a wall-resolved method computed on a hybrid tetrahedral–prismatic grid. These two approaches are tested against the square-cylinder case at moderate Reynolds number (Re=22,050), in which many reference data are available for flow dynamics and heat transfer. Both predict accurately the unsteady flow around the cylinder and in its near wake, but only the wall-resolved approach reproduces the Nusselt-number global value and its spatial distribution around the cylinder wall. This latter method is used to investigate the coupling between periodic vortex shedding and wall heat transfer using a phase-averaged analysis.
},
url = {http://arc.aiaa.org/doi/abs/10.2514/1.J051800}}

Jauré, S., Duchaine, F., Staffelbach, G. and Gicquel, L.Y.M. (2013) Massively parallel conjugate heat transfer methods relying on large eddy simulation applied to an aeronautical combustor, Computational Science and Discovery, 6 (1) , pp.

[bibtex]

@article{AR-CFD-13-21063,
author = {Jaur´{e}, S. and Duchaine, F. and Staffelbach, G. and Gicquel, L.Y.M. },
title = {Massively parallel conjugate heat transfer methods relying on large eddy simulation applied to an aeronautical combustor},
year = {2013},
number = {1},
volume = {6},
pages = {},
journal = {Computational Science and Discovery}}

Collado, E., Gourdain, N., Duchaine, F. and Gicquel, L.Y.M. (2012) Effects of free-stream turbulence on high pressure turbine blade heat transfer predicted by structured and unstructured LES, Journal of Heat and Mass Transfer, 55 (21-22) , pp. 5754 - 5768

[bibtex]
[url]

@article{AR-CFD-12-20689,
author = {Collado, E. and Gourdain, N. and Duchaine, F. and Gicquel, L.Y.M. },
title = {Effects of free-stream turbulence on high pressure turbine blade heat transfer predicted by structured and unstructured LES},
year = {2012},
number = {21-22},
volume = {55},
pages = {5754 - 5768},
journal = {Journal of Heat and Mass Transfer},
url = {http://www.cerfacs.fr/~cfdbib/repository/TR_CFD_12_28.pdf}}

Poitou, D., Amaya, J. and Duchaine, F. (2012) Parallel computation for the radiative heat transfer using the DOM in combustion applications: direction, frequency, sub-domain decompositions and hybrid methods, Numerical Heat Transfer, Part B Fundamentals, 62 (1) , pp. 28 - 49

[bibtex]

@article{AR-CFD-12-21426,
author = {Poitou, D. and Amaya, J. and Duchaine, F. },
title = {Parallel computation for the radiative heat transfer using the DOM in combustion applications: direction, frequency, sub-domain decompositions and hybrid methods},
year = {2012},
number = {1},
volume = {62},
pages = {28 - 49},
journal = {Numerical Heat Transfer, Part B Fundamentals}}

Duchaine, F., Boudy, F., Durox, D. and Poinsot, Th. (2011) Sensitivity analysis of transfer functions of laminar flames, Combustion and Flame, 158 (12) , pp. 2384 - 2394

[bibtex]

@ARTICLE{AR-CFD-11-20838,
author = {Duchaine, F. and Boudy, F. and Durox, D. and Poinsot, Th. },
title = {Sensitivity analysis of transfer functions of laminar flames},
year = {2011},
number = {12},
volume = {158},
pages = {2384 - 2394},
journal = {Combustion and Flame}}

Duchaine, F., Morel, T. and Gicquel, L.Y.M. (2009) Computational-fluid-dynamics-based kriging optimization tool for aeronautical combustion chambers, AIAA Journal, 47 (3) , pp. 631 - 645, doi: 10.2514/1.37808

[bibtex]
[url]

@ARTICLE{AR-CFD-09-20835,
author = {Duchaine, F. and Morel, T. and Gicquel, L.Y.M. },
title = {Computational-fluid-dynamics-based kriging optimization tool for aeronautical combustion chambers},
year = {2009},
number = {3},
volume = {47},
pages = {631 - 645},
doi = {10.2514/1.37808},
journal = {AIAA Journal},
abstract = {Current Computational Fluid Dynamics (CFD) state-of-the-art provides reasonable reacting low predictions and is already used in industry to evaluate new concepts of gas turbine engines. In parallel, the maturity of the optimization field is evidenced and numerous industrial activities benefit from enhanced search algorithms. With the advent of massively parallel architectures, the intersection between these two advanced techniques seems a logical path to yield fully automated decision making tools for the design of gas turbine engines. Such new tools need however to be constructed with care to remain manageable and to take advantage of the current computing power while satisfying industrial constraints. In the following, the coupling device PALM contains a fully encapsulated algorithm based on a multi-objective optimization strategy making use of a meta-model (kriging) approach coupled with a design of experiments and a fully parallel three dimensional CFD solver to model the physics. Preliminary evaluations on the search algorithm against simple analytical functions prove the constructed optimization algorithm to be efficient and robust as long as model parameters are supplied properly. The application to an industrial aeronautical combustion chamber demonstrates the strategy to be feasible with decent computing power and potential design changes are indicated to improve performance and durability of the studied engine.
},
url = {http://www.cerfacs.fr/~cfdbib/repository/TR_CFD_08_38.pdf}}

Duchaine, F., Corpron, A., Pons, L., Moureau, V., Nicoud, F. and Poinsot, Th. (2009) Development and assessment of a coupled strategy for conjugate heat transfer with Large Eddy Simulation. application to a cooled turbine blade, International Journal of Heat and Fluid Flow, 30 (6)

[bibtex]

@ARTICLE{AR-CFD-09-20836,
author = {Duchaine, F. and Corpron, A. and Pons, L. and Moureau, V. and Nicoud, F. and Poinsot, Th. },
title = {Development and assessment of a coupled strategy for conjugate heat transfer with Large Eddy Simulation. application to a cooled turbine blade},
year = {2009},
number = {6},
volume = {30},
journal = {International Journal of Heat and Fluid Flow}}

Duchaine, F., Mendez, S., Nicoud, F., Corpron, A., Moureau, V. and Poinsot, Th. (2009) Conjugate heat transfer with Large Eddy Simulation for gas turbine components, Comptes Rendus Mécanique, 337 (6-7) , pp. 550 - 561

[bibtex]

@ARTICLE{AR-CFD-09-20837,
author = {Duchaine, F. and Mendez, S. and Nicoud, F. and Corpron, A. and Moureau, V. and Poinsot, Th. },
title = {Conjugate heat transfer with Large Eddy Simulation for gas turbine components},
year = {2009},
number = {6-7},
volume = {337},
pages = {550 - 561},
journal = {Comptes Rendus Mécanique}}

Gourdain, N., Gicquel, L.Y.M., Staffelbach, G., Vermorel, O., Duchaine, F., Boussuge, J.-F. and Poinsot, T. (2009) High performance parallel computing of flows in complex geometries - part 2: applications, Computational Science and Discovery, 2, pp. 015004

[bibtex]
[url]

@ARTICLE{AR-CFD-09-20993,
author = {Gourdain, N. and Gicquel, L.Y.M. and Staffelbach, G. and Vermorel, O. and Duchaine, F. and Boussuge, J.-F. and Poinsot, T. },
title = {High performance parallel computing of flows in complex geometries - part 2: applications},
year = {2009},
number = {November},
volume = {2},
pages = {015004},
journal = {Computational Science and Discovery},
abstract = {Present regulations in terms of pollutant emissions, noise and economical
constraints, require new approaches and designs in the fields of energy supply and
transportation. It is now well established that the next breakthrough will come from a
better understanding of unsteady flow effects and by considering the entire system and not
only isolated components. However, these aspects are still not well taken into account by
the numerical approaches or understood whatever the design stage considered. The main
challenge is essentially due to the computational requirements inferred by such complex
systems if it is to be simulated by use of supercomputers. This paper shows how new
challenges can be addressed by using parallel computing platforms for distinct elements of
a more complex systems as encountered in aeronautical applications. Based on numerical
simulations performed with modern aerodynamic and reactive flow solvers, this work
underlines the interest of high-performance computing for solving flow in complex industrial
configurations such as aircrafts, combustion chambers and turbomachines. Performance
indicators related to parallel computing efficiency are presented, showing that establishing
fair criterions is a difficult task for complex industrial applications. Examples of numerical
simulations performed in industrial systems are also described with a particular interest for
the computational time and the potential design improvements obtained with high-fidelity and
multi-physics computing methods. These simulations use either unsteady Reynolds-averaged
Navier–Stokes methods or large eddy simulation and deal with turbulent unsteady flows, such
as coupled flow phenomena (thermo-acoustic instabilities, buffet, etc). Some examples of the
difficulties with grid generation and data analysis are also presented when dealing with these
complex industrial applications.},
url = {http://iopscience.iop.org/article/10.1088/1749-4699/2/1/015004/pdf}}

Duchaine, F., Morel, T. and Gicquel, L.Y.M. (2009) Computational-fluid-dynamics-based kriging optimization tool for aeronautical combustion chambers, AIAA Journal, 47, pp. 631 - 645

[bibtex]

@ARTICLE{AR-CMGC-09-21993,
author = {Duchaine, F. and Morel, T. and Gicquel, L.Y.M. },
title = {Computational-fluid-dynamics-based kriging optimization tool for aeronautical combustion chambers},
year = {2009},
volume = {47},
pages = {631 - 645},
journal = {AIAA Journal}}

Gout, C., Papadogiannis, D., Dombard, J., Duchaine, F., Gicquel, L.Y.M. and Odier, N. (2021) Assessment of profile transformation for turbomachinery large eddy simulations - from academic to industrial applications - invited conference, Proceedings of ASME Turbo Expo, June 7-11. 2021, doi: 10.1115/GT2021-59293

[bibtex]
[url]

@CONFERENCE{PR-CFD-21-123,
author = {Gout, C. and Papadogiannis, D. and Dombard, J. and Duchaine, F. and Gicquel, L.Y.M. and Odier, N. },
title = {Assessment of profile transformation for turbomachinery large eddy simulations - from academic to industrial applications - invited conference},
year = {2021},
booktitle = {Proceedings of ASME Turbo Expo, June 7-11},
volume = {V02CT34A020},
pages = {GT2021-59293},
doi = {10.1115/GT2021-59293},
abstract = {Large Eddy Simulation (LES) of turbomachinery stages has
been recently brought to attention due to its potential increased
prediction fidelity and its reduced dependency to modeling. Such
simulations are however often very CPU intensive, with potentially
long return times and only possible for reduced periodic
sectors. For real applications, such limitations are prohibitive
for a daily use in a design phase. Indeed, most industrial turbomachinery
applications rely on designs where at least one of the
blade rows has a prime number of blades. Full 360simulations
are in such a case required for appropriate flow dynamics predictions,
which implies prohibitive computational costs although
recent demonstrations prove these feasible. To make LES affordable
in an industrial context, it is clearly necessary to find ways
to reduce its cost and return time, one approach being the reduction
of the computational domain size.
The Profile Transformation Approach (PTA) is one of such
specific methods that allows to simulate down to a single blade
passage per blade row, thus decreasing the domain size of the
problem and its CPU cost. PTA has been devised and validated
in a URANS context and its limits are well known in this specific
context. In terms of development and implementation in a
code, PTA essentially consists in re-scaling the flow field at the
rotor/stator interface to comply with the geometrical constraints
on both sides of the interface since these often have different angular
extents. Thanks to this flow re-scaling, periodic flow conditions
can be applied on the azimuthal limits of both domains
while retaining only one passage per row. In the following, the
method is assessed in the context of fully unsteady LES simulations
in an attempt to identify generated approximations and
errors. This LES approach is then used to address a set of cases
of increasing complexity ranging from the academic problem focusing
first on the convection of a vortex across an interface and
finishing with simulations of industrial relevance.},
keywords = {Profile transformation, turbomachinery, LES, phase lag},
url = {https://asmedigitalcollection.asme.org/GT/proceedings-abstract/GT2021/84928/V02CT34A020/1119761}}

Pérez-Arroyo, C., Dombard, J., Duchaine, F., Odier, N., Exilard, G., Richard, S., Buffaz, N. and Démolis, J. (2020) Large-eddy Simulation of an integrated high-pressure compressor and combustion chamber of a typical turbine engine architecture, Proceedings of ASME Turbo Expo 2020 Turbomachinery Technical Conference and Exposition., Virtual conference, 6 2020, doi: 10.1115/GT2020-16288

[bibtex]
[url]

@CONFERENCE{PR-CFD-20-130,
author = {Pérez-Arroyo, C. and Dombard, J. and Duchaine, F. and Odier, N. and Exilard, G. and Richard, S. and Buffaz, N. and Démolis, J. },
title = {Large-eddy Simulation of an integrated high-pressure compressor and combustion chamber of a typical turbine engine architecture},
year = {2020},
month = {6},
booktitle = {Proceedings of ASME Turbo Expo 2020 Turbomachinery Technical Conference and Exposition},
volume = {2C},
number = {V02CT35A058 },
series = {GT2020-16288},
pages = {1-10},
address = {Virtual conference},
doi = {10.1115/GT2020-16288},
abstract = {The design optimization of aviation propulsion systems by means of computational fluid dynamics is key to increase their efficiency and reduce pollutant and noise emissions. The recurrent increase in available computing power allows nowadays to perform unsteady high-fidelity computations of the different components of a gas turbine. However, these simulations are often made independently of each other and they only share average quantities at interfaces. In this work, the methodology and first results for a sectoral large-eddy simulation of an integrated high-pressure compressor and combustion chamber of a typical turbine engine architecture is proposed. In the simulation, the compressor is composed of one main blade and one splitter blade, two radial diffuser vanes and six axial diffuser vanes. The combustion chamber is composed of the contouring casing, the flame-tube and a T-shaped vaporizer. This integrated computation considers a good trade-off between accuracy of the simulation and affordable CPU cost. Results are compared between the stand-alone combustion chamber simulation and the integrated one in terms of global, integral and average quantities. It is shown that pressure perturbations generated by the interaction of the impeller blades with the diffuser vanes are propagated through the axial diffuser and enter the combustion chamber through the dilution holes and the vaporizer. Due to the high amplitude of the pressure perturbations, several variables are perturbed at the blade-passing frequency and multiples. This is also reflected on combustion where two broadband peaks appear for the global heat release.},
keywords = {Turbomachinery, Radial Compressor, Combustion chamber, Coupling, LES},
url = {https://asmedigitalcollection.asme.org/GT/proceedings-abstract/GT2020/84089/V02CT35A058/1094567}}

Martin, B., Duchaine, F., Gicquel, L.Y.M., Odier, N. and Dombard, J. (2020) Wall-resolved Large-Eddy Simulation of the LES89 cascade using an explicit local time-stepping method, ASME TURBO EXPO 2020, Gas Turbine Technical Congress & Exposition., Virtual conference 2020, doi: 10.1115/GT2020-14171

[bibtex]
[url]

@CONFERENCE{PR-CFD-20-134,
author = {Martin, B. and Duchaine, F. and Gicquel, L.Y.M. and Odier, N. and Dombard, J. },
title = {Wall-resolved Large-Eddy Simulation of the LES89 cascade using an explicit local time-stepping method},
year = {2020},
booktitle = {ASME TURBO EXPO 2020, Gas Turbine Technical Congress & Exposition},
volume = {2C},
number = {V02CT35A001},
pages = {GT2020-14171},
address = {Virtual conference},
doi = {10.1115/GT2020-14171},
abstract = {Today, most turbomachinery CFD simulations rely on computational domains where a large heterogeneity of mesh refinement is present, targeting specific flow regions while relaxing the mesh size in regions of lesser interest. For example, in the context of wall-resolved Large-Eddy Simulations (LES), typical cell size ratios between the main stream grid resolution and the near-wall regions may reach several orders of magnitude. Although justifying the use of multi-element solvers, such a local refinement / coarsening strategy usually results in a very stringent time step selection especially in the context of compressible flows necessary for turbomachinery applications. For performance, such code algorithms usually rely on explicit time-advancement methods which are very efficiently parallelized. However, this comes with the cost of stability constraints which in the context of multi-element solvers and grid refinement can rapidly be very limiting. The alternative is the use of an implicit time-advancement with the indirect cost of a major coding effort to obtain efficient parallelisation but also with the risk of arbitrarily selecting a time step that may not allow the proper time scale resolution necessary to predict such highly turbulent flows given a grid. Another consequence of grid heterogeneity is that its imposes a single time step for the entire domain of simulation (i.e. the smallest cell CFL condition), which is in most other cells smaller than necessary. Such a choice again greatly reduces the simulation efficiency since the optimal local CFL of a given scheme is only applicable to a small subset of points of the entire grid. One way to address this issue is to introduce the notion of Local Time-Stepping (LTS). With this formalism, one proposes to divide a given computational domain into sub-domains and associated grids composed of comparable cell sizes. Compressible Navier-Stokes equations are then solved simultaneously for each sub-grid with its dedicated time step meeting the local grid optimal CFL condition. Implemented in the LES explicit solver AVBP, a massively parallel cell-vertex based compressible solver, capable of handling unstructured hybrid meshes, LTS is assessed for configurations where layers of prisms are used in the near-wall region of the blade and tetrahedra are used in the rest of the domain. Both sub-grids are then coupled with an overset grid method, the overlap region between the two grids making use of an interpolation to exchange information. In the following, LTS is first tested and validated for basic test cases: one simple 1D travelling acoustic wave and a vortex propagation test case to confirm the suitability of such a technique, evaluate gains and prove its ability to recover numerical scheme orders. It is then applied to the LS89 cascade turbomachinery flow. For this last case, the computational domain is divided in two grids: one containing the blade wall and its vicinity; and a second one covering the rest of the domain. Results obtained with wall-resolved LES’s using a single domain and LTS are compared to the experimental data to evaluate the impact on the flow predictions. Overall, for the LS89 configuration that is known as challenging, there is a good agreement between simulations and experiment. More importantly, the results are almost identical when comparing the single domain and the LTS cases despite the significant simulation cost reduction for the latter.},
url = {https://asmedigitalcollection.asme.org/GT/proceedings-abstract/GT2020/84089/V02CT35A001/1094473}}

Agarwal, S., Gicquel, L.Y.M., Duchaine, F., Odier, N. and Dombard, J. (2020) Analysis of the unsteady flow field inside a fan-shaped cooling Hole predicted by Large-Eddy Simulation, Proceedings of ASME Turbo Expo 2020 - September 21-25, 2020., Virtual conference 2020

[bibtex]
[url]

@CONFERENCE{PR-CFD-20-184,
author = {Agarwal, S. and Gicquel, L.Y.M. and Duchaine, F. and Odier, N. and Dombard, J. },
title = {Analysis of the unsteady flow field inside a fan-shaped cooling Hole predicted by Large-Eddy Simulation},
year = {2020},
booktitle = {Proceedings of ASME Turbo Expo 2020 - September 21-25, 2020},
pages = {GT2020-14201},
address = {Virtual conference},
abstract = {Film cooling is a common technique to manage turbine vane and blade thermal environment. Optimization of the film cooling efficiency through efficient cooling hole shape design and appropriate control of operating conditions is still an active academic and industrial topic. In this context, the analysis of the flow issued by a film cooling hole is an important and fundamental research axis to develop proper understanding of film cooling physics. Recently, a lot of emphasis has been put on the creation of empirical models to substitute for the flow calculation inside cooling holes. The reliability of such models however relies on the proper understanding of the flow inside the hole. Using Large Eddy Simulation (LES), it can be shown that the flow in the perforation has a significant impact on the film cooling effectiveness.
The present work attends to understand such a mechanism by specifically addressing the 7-7-7 fan-shaped cooling hole [1]. In the current study, the LES flow predictions are first validated against the experimental data base available from Penn State University in terms of aerodynamics and adiabatic effectiveness. The flow features inside the hole are then more specifically studied with the objective of identifying the dominant flow characteristics and vortex structures. To do so, mathematical techniques such as the Fast Fourier Transforms (FFT) and Dynamic Mode Decomposition (DMD) are used to quantitively access the flow modal structure inside the hole. From this analysis, one retains that after entering the hole from the plenum side, the flow turns sharply forming a separation region and an internal shear layer is formed at the interface of this separation zone. As a consequence, periodically shed vortices appear due to the the roll-up of this shear layer. This vortex shedding is predominant in the cylindrical part of the hole but once the hole expands and the cross-section changes, flow adaptation occurs. Indeed, the lateral and forward hole expansion is followed by a decrease of the in hole flow velocity. This leads to a reorganization of the flow with vortex paring and breakdown as well as the establishment of a second separation region. The main outcome of this complex flow is a rather uniform turbulent flow profile formed at the hole exit. In agreement with the literature, such a process suppresses the vortices shed near the hole-entry which if escape from the cooling hole have been shown to not always be beneficial to the film cooling performance.
[1] R. P. Schroeder and K. A. Thole, Adiabatic effectiveness measurements for a baseline shaped film cooling hole, GT2014-25992. in Proceedings of ASME Turbo Expo 2014: Turbine Technical Conference and Exposition, June 16 – 20, 2014, Düsseldorf, Germany
},
url = {https://asme-turboexpo.secure-platform.com/a/solicitations/105/sessiongallery/5233}}

Agarwal, S., Gicquel, L.Y.M., Duchaine, F., Odier, N. and Dombard, J. (2020) Effect of the in-hole vortical structures on the cylindrical-hole Film-cooling effectivenessEffect of the in-hole vortical structures on the cylindrical-hole Film-cooling effectiveness, Proceedings of ASME Turbo Expo 2020., Virtual conference 2020

[bibtex]
[url]

@CONFERENCE{PR-CFD-20-185,
author = {Agarwal, S. and Gicquel, L.Y.M. and Duchaine, F. and Odier, N. and Dombard, J. },
title = {Effect of the in-hole vortical structures on the cylindrical-hole Film-cooling effectivenessEffect of the in-hole vortical structures on the cylindrical-hole Film-cooling effectiveness},
year = {2020},
booktitle = {Proceedings of ASME Turbo Expo 2020},
pages = {GT2020-14258},
address = {Virtual conference},
abstract = {Understanding the flow from a cooling hole is very important to be able to properly control film cooling of turbine blades.
For this purpose, large eddy simulation (LES) investigation of
the flow inside a cylindrical film cooling hole is presented in
this paper. Two different geometries, with different hole metering lengths, are investigated at a blowing ratio of 0.5. The main
flow structure in the hole are the hairpin vortices that originate
from a shear layer formed due to flow separation near the hole
entry. The comparison of these hairpin vortices in the two cases
with different hole metering length is presented in detail. The results show that in case of the hole with longer length the hairpin
vortices dissociate within the hole itself. In such a case a uniform flow is seen at the hole exit. However, when the hole length
is significantly decreased, it is shown that these vortices exit the
hole and effect the vortex structures outside the hole, thereby accounting for the reduction in film cooling effectiveness. Overall,
these results bring forth one other major reason for the reduction
in film cooling effectiveness with reduction in hole length, i.e. the
exit of in-hole hairpin vortices into the crossflow.},
keywords = {film cooling, LES, Reynolds Averaged Navier-Stokes},
url = {https://asme-turboexpo.secure-platform.com/a/solicitations/105/sessiongallery/5233/application/45770}}

Dombard, J., Duchaine, F., Gicquel, L.Y.M., Odier, N., Leroy, K., Le-Guyader, S., Buffaz, N., Démolis, J., Richard, S. and Grosnickel, T. (2020) Evaluation of the capacity of rans/urans/les in predicting the performance of a high-pressure turbine: effect of load and Off design condition, Proceedings of ASME Turbo Expo 2020., Virtual conference 2020

[bibtex]
[url]

@CONFERENCE{PR-CFD-20-186,
author = {Dombard, J. and Duchaine, F. and Gicquel, L.Y.M. and Odier, N. and Leroy, K. and Le-Guyader, S. and Buffaz, N. and Démolis, J. and Richard, S. and Grosnickel, T. },
title = {Evaluation of the capacity of rans/urans/les in predicting the performance of a high-pressure turbine: effect of load and Off design condition},
year = {2020},
booktitle = {Proceedings of ASME Turbo Expo 2020},
pages = {GT2020-15447},
address = {Virtual conference},
abstract = {This paper aims at addressing design issues of turbomachinery configurations by use of Large-Eddy Simulation (LES). To do so, a research state-of-the-art high-pressure turbine stage, without technological details and for which experimental data are available, is computed with the three methods: i.e. RANS, URANS and LES. Starting from the nominal operating design,
a database is acquired varying the design space (three Zweifel numbers), load (three pressure rates) and rotation speed (three reduced speeds). The analysis of the database is carried out incrementally from a design perspective. Numerical results are systematically compared to experimental ones. Main conclusions are threefold: 1/ Calibrated RANS provides excellent results at the nominal operating point but lacks of accuracy at off design conditions. Only unsteady methods (both URANS and LES) allow a good agreement with experiment along the whole database. 2/ Although very good on the overall performances, LES provides radial profiles and 2D maps leaving room for improvement in comparison with the URANS predictions.
3/ LES and standard law-of-the-wall is validated against experiments in a high-pressure turbine without technological details but still representative of a realistic and recent industrial design. From an aero design point, this paper shows the interest in using URANS for off design conditions. It also represents a milestone for LES that had to be passed before addressing more
complex issues which URANS hardly addresses.},
keywords = {HIGH-PRESSURE TURBINE, RANS/URANS/LES},
url = {https://asme-turboexpo.secure-platform.com/a/solicitations/105/sessiongallery/5300/application/46691}}

Harnieh, M., Odier, N., Dombard, J., Duchaine, F. and Gicquel, L.Y.M. (2020) Loss predictions in the high-pressure film-cooled turbin vane of the factor project by mean of wall-modeled Large Eddy Simulation, Proceedings of ASME Turbo Expo 2020., Virtual conference 2020

[bibtex]
[url]

@CONFERENCE{PR-CFD-20-187,
author = {Harnieh, M. and Odier, N. and Dombard, J. and Duchaine, F. and Gicquel, L.Y.M. },
title = {Loss predictions in the high-pressure film-cooled turbin vane of the factor project by mean of wall-modeled Large Eddy Simulation},
year = {2020},
booktitle = {Proceedings of ASME Turbo Expo 2020},
pages = {GT2020-14232},
address = {Virtual conference },
abstract = {The use of numerical simulations to design and optimize turbine
vane cooling requires precise prediction of the fluid mechanics
and film cooling effectiveness. This results in the need to
numerically identify and assess the various origins of the losses
taking place in such systems and if possible in engine representative
conditions. Large-Eddy Simulation (LES) has shown recently
its ability to predict turbomachinery flows in well mastered
academic cases such as compressor or turbine cascades. When
it comes to industrial representative configurations, the geometrical
complexities, high Reynolds and Mach numbers as well as
boundary condition setup lead to an important increase of CPU
cost of the simulations. To evaluate the capacity of LES to predict
film cooling effectiveness as well as to investigate the loss
generation mechanisms in a turbine vane in engine representative
conditions, a wall-modeled LES of the FACTOR film-cooled
nozzle is performed. After the comparison of integrated values
to validate the operating point of the vanes, the mean flow structure
is investigated. In the coolant film, a strong turbulent mixing
process between coolant and hot flows is observed. As a result,
the spatial distribution of time-averaged vane surface temperature
is highly heterogeneous. Comparisons with the experiment
show that the LES prediction fairly reproduces the spatial distribution
of the adiabatic film effectiveness. The loss generation in
the configuration is then investigated. To do so, two methodologies,
i.e, performing balance of total pressure in the vanes wakes
as mainly used in the literature and Second Law Analysis (SLA)
are evaluated. Balance of total pressure without the contribution
of thermal effects only highlights the losses generated by the
wakes and secondary flows. To overcome this limitation, SLA
is adopted by investigating loss maps. Thanks to this approach,
mixing losses are shown to dominate in the coolant film while
aerodynamic losses dominate in the coolant pipe region},
keywords = {CFD, LES, RANS, URANS, Aerodynamic},
url = {https://asme-turboexpo.secure-platform.com/a/solicitations/105/sessiongallery/5377/application/45740}}

Harnieh, M., Odier, N., Dombard, J., Duchaine, F. and Gicquel, L.Y.M. (2020) Loss Predictions in the High-Pressure Film-Cooled Turbine Blade Cascade T120D by Mean of Wall-Resolved Large Eddy Simulation, Proceedings of ASME Turbo Expo 2020., virtual conference 2020

[bibtex]
[url]

@CONFERENCE{PR-CFD-20-188,
author = {Harnieh, M. and Odier, N. and Dombard, J. and Duchaine, F. and Gicquel, L.Y.M. },
title = { Loss Predictions in the High-Pressure Film-Cooled Turbine Blade Cascade T120D by Mean of Wall-Resolved Large Eddy Simulation},
year = {2020},
booktitle = {Proceedings of ASME Turbo Expo 2020},
pages = {GT2020-14231},
address = {virtual conference},
abstract = {Film cooling is commonly used to protect turbine vanes and
blades from the hot gases produced in the combustion chamber.
The design and optimization of these systems can however only
be achieved if a precise prediction of the fluid mechanics and film
efficiency is guaranteed at a level where induced losses are fully
mastered. Such a prerequisite induces at the numerical level to
be able to identify and assess losses. In this context, the present
study addresses loss assessment in a wall-resolved Large Eddy
Simulation (LES) of the film-cooled high-pressure turbine blade
cascade T120D from the European project AITEB II. The objectives
are twofolds: (1) to evaluate the capacity of LES to predict
adiabatic film cooling effectiveness in a mastered academic
case; and (2) to investigate loss generation mechanisms in a fully
anisothermal configuration. When it comes to LES predictions of
T120D, the flow structure around the blade and the coolant jet
organization are coherent with literature findings. Satisfactory
agreements are furthermore retrieved for the pressure load prediction
as well as the adiabatic film effectiveness if compared to
the experiment. Loss generation is then investigated illustrating
the fact that aerodynamics losses dominate mixing losses which
are mainly located in the coolant film. This is in line with the
temperature difference between the hot and coolant flows that is
low for this experimental condition. Distinct contributions can
however be made available by studying the local loss generation
maps by means of Second Law Analysis if recast in the specific
context of anisothermal flows when simulated by LES.},
keywords = {CFD},
url = {https://asme-turboexpo.secure-platform.com/a/solicitations/105/sessiongallery/5376/application/45521}}

Perrot, A., Duchaine, F., Gicquel, L.Y.M., Grosnickel, T., Odier, N. and Dombard, J. (2020) Unsteady analysis of heat transfer coefficient distribution in a static ribbed channel for an established flow, Proceedings of ASME Turbo Expo 2020., virtual conference 2020

[bibtex]
[url]

@CONFERENCE{PR-CFD-20-189,
author = {Perrot, A. and Duchaine, F. and Gicquel, L.Y.M. and Grosnickel, T. and Odier, N. and Dombard, J. },
title = {Unsteady analysis of heat transfer coefficient distribution in a static ribbed channel for an established flow},
year = {2020},
booktitle = {Proceedings of ASME Turbo Expo 2020},
pages = {GT2020-14493},
address = {virtual conference},
abstract = {Turbulent ribbed channels are extensively used in turbomachinery
to enhance convective heat transfer in internally-cooled
components like turbine blades. One of the key aspect of such
a problem is the distribution of the Heat Transfer Coefficient
(HTC) in fully developed flows and many studies have addressed
this problem by use of Computational Fluid Dynamics (CFD). In
the present document, Large Eddy Simulation (LES) is performed
for a configuration from a test-rig at the Von Karman Institute
representing a square channel with periodic square ribs. The
whole channel is computed in an attempt to better understand
HTC maps in this specific configuration. Resulting mean and
unsteady flow features are captured and predictions are used to
further explain the obtained HTC distribution. More specifically
turbulent structures are seen to bring cold gas from the main
flow to the wall. A statistical analysis of these events using the
joint velocity-temperature PDF and quadrant method allows to
define 4 types of events happening at every location of the channel
and which can then be linked to the HTC distribution. First
the HTC is very high where the flow impacts the wall with cold
temperature whereas it is lower where the hot gas is ejected to
the main flow. In an attempt to link the HTC trace on the channel
wall with structures in the flow field far-off the wall, the main
modes are identified performing Power Spectral Density (PSD)
analysis of the velocity along the channel. Dynamic Mode Decomposition
(DMD) of the flow field data is then used to present
the spatio-temporal characteristics of two of the identified most
dominant modes : a vortex-street mode linked to the first rib and
a rib-to-rib mode appearing because of the quasi-periodicity of
the configuration. However DMD analysis of the HTC trace on
the wall does not emphasize any dominant mode. This indicates
a weak link between the main flow large scale features and the
instantaneous and more local HTC distribution.},
keywords = {CFD},
url = {https://asme-turboexpo.secure-platform.com/a/solicitations/105/sessiongallery/5211/application/45778}}

Martin, B., Thomas, M., Dombard, J., Duchaine, F. and Gicquel, L.Y.M. (2019) Analysis of solid particle ingestion and dynamics in a turbomachine using Large-Eddy Simulation, Proceedings of the ASME 2019 Turbo Expo: Turbomachinery Technical Conference & Exposition Turbomachines for Clean Power and Propulsion Systems., Phoenix, USA, 6 2019, doi: 10.1115/GT2019-91215

[bibtex]
[url]

@CONFERENCE{PR-CFD-19-96,
author = {Martin, B. and Thomas, M. and Dombard, J. and Duchaine, F. and Gicquel, L.Y.M. },
title = {Analysis of solid particle ingestion and dynamics in a turbomachine using Large-Eddy Simulation},
year = {2019},
month = {6},
booktitle = {Proceedings of the ASME 2019 Turbo Expo: Turbomachinery Technical Conference & Exposition Turbomachines for Clean Power and Propulsion Systems},
volume = {2D},
number = {GT2019-91215},
pages = {pp 1-13},
address = {Phoenix, USA},
doi = {10.1115/GT2019-91215},
abstract = {Erosion of compressor and turbine blades operating in extreme environment fouled with sand particles, ash or soot is a serious problem for gas turbine manufacturers and users. Indeed, operation of a gas turbine engine in such hostile conditions leads to drastic degradation of the aerodynamic performance of the components, mostly through surface roughness modification, tip clearance height increase or blunting of blade leading edges. To evaluate associated risks, the computation of particle trajectories and impacts through multiple turbomachinery stages by Computational Fluid Dynamics (CFD) seems a decent path but remains a challenge. The numerical prediction of complex turbulent flows in compressors and turbines is however necessary in such a context and validations are still required. Recently, Large-Eddy Simulation (LES) has shown promising results for compressor and turbine configurations for a wide range of operating conditions at an acceptable cost. With this in mind, this article presents the assessment of a LES solver able to treat turbomachine configurations to predict solid particle motion. To do so, the governing equations of particle dynamics are introduced using the Lagrangian formalism and are solved to compute locations and conditions of impact, namely particle velocity, angle and radius. The fully unsteady and coupled strategy is applied to blade geometries for studying the main areas and conditions of impacts obtained with LES. For comparison, a one-way coupling computation based on a mean steady flow field where only the Lagrangian particles are advanced in time is performed to evaluate the gain and drawbacks of both methods},
url = {https://asmedigitalcollection.asme.org/GT/proceedings-abstract/GT2019/58585/V02DT47A013/1066593}}

Papadogiannis, D., Mouriaux, S., Cagnone, J.-S., Hillewaert, K., Duchaine, F. and Hiernaux, S. (2019) Influence of the numerical strategy on wall-resolved LES of a compressor cascade, European Turbomachinery Conference ETC13., Lausanne, Switzerland 2019

[bibtex]

@CONFERENCE{PR-CFD-19-98,
author = {Papadogiannis, D. and Mouriaux, S. and Cagnone, J.-S. and Hillewaert, K. and Duchaine, F. and Hiernaux, S. },
title = {Influence of the numerical strategy on wall-resolved LES of a compressor cascade},
year = {2019},
booktitle = {European Turbomachinery Conference ETC13},
address = {Lausanne, Switzerland}}

Duchaine, F. (2019) Invited conference - Conjugate heat transfer methodologies for gas turbine combustion aero thermal investigation, ASME TurboExpo 2019., Phoenix, USA, 6 2019

[bibtex]

@CONFERENCE{PR-CFD-19-99,
author = {Duchaine, F. },
title = {Invited conference - Conjugate heat transfer methodologies for gas turbine combustion aero thermal investigation},
year = {2019},
month = {6},
booktitle = {ASME TurboExpo 2019},
address = {Phoenix, USA}}

Thomas, M., Dombard, J., Duchaine, F., Gicquel, L.Y.M. and Koupper, C. (2019) Large-Eddy Simulation of combustor and complete single-stage high-pressure turbine of the FACTOR test rig, Phoenix, AZ, USA, 6 2019

[bibtex]

@CONFERENCE{PR-CFD-19-100,
author = {Thomas, M. and Dombard, J. and Duchaine, F. and Gicquel, L.Y.M. and Koupper, C. },
title = {Large-Eddy Simulation of combustor and complete single-stage high-pressure turbine of the FACTOR test rig},
year = {2019},
month = {6},
pages = {GT2019-91206},
address = {Phoenix, AZ, USA}}

Grosnickel, T., Duchaine, F., Gicquel, L.Y.M. and Koupper, C. (2019) Large-Eddy Simulation of the flow developing in static and rotating ribbed channels, ASME TurboExpo 2019., Phoenix, AZ, USA, 6 2019

[bibtex]

@CONFERENCE{PR-CFD-19-101,
author = {Grosnickel, T. and Duchaine, F. and Gicquel, L.Y.M. and Koupper, C. },
title = {Large-Eddy Simulation of the flow developing in static and rotating ribbed channels},
year = {2019},
month = {6},
booktitle = {ASME TurboExpo 2019},
pages = {GT2019-90370},
address = {Phoenix, AZ, USA}}

Pouech, P., Duchaine, F. and Poinsot, T. (2019) Ignition of a premixed methane-air flow over a turbulent backward-facing step by Direct Numerical Simulation, 17th International Conference on Numerical Combustion., Aachen (Germany) 2019

[bibtex]

@CONFERENCE{PR-CFD-19-103,
author = {Pouech, P. and Duchaine, F. and Poinsot, T. },
title = {Ignition of a premixed methane-air flow over a turbulent backward-facing step by Direct Numerical Simulation},
year = {2019},
booktitle = {17th International Conference on Numerical Combustion},
address = {Aachen (Germany)},
abstract = {slides},
keywords = {COMBUSTION}}

Esnault, S., Duchaine, F. and Gicquel, L.Y.M. (2019) Large-Eddy Simulations of heat transfer within a multi-perforation synthetic jets configuration, ASME Turbo Expo 2019: Turbine Technical Conference and Exposition., Phoenix, Arizona, USA, 6 2019

[bibtex]

@CONFERENCE{PR-CFD-19-105,
author = {Esnault, S. and Duchaine, F. and Gicquel, L.Y.M. },
title = {Large-Eddy Simulations of heat transfer within a multi-perforation synthetic jets configuration},
year = {2019},
month = {6},
booktitle = {ASME Turbo Expo 2019: Turbine Technical Conference and Exposition},
pages = {GT2019-91375},
address = {Phoenix, Arizona, USA},
abstract = { Synthetic jets are produced by devices that enable a suction phase followed by an ejection phase. The resulting mean mass budget is hence null and no addition of mass in the system is required. These particular jets have especially been considered for some years for flow control applications. They also display features that can become of interest to enhance heat exchanges, for example for wall cooling issues. Synthetic jets can be generated through different mechanisms, such as acoustics by making use of a Helmholtz resonator or through the motion of a piston as in an experience mounted at Institut Pprime in France. The objective of this specific experiment is to understand how synthetic jets can enhance heat transfer in a multi-perforated configuration. As a complement to this experimental set up, Large-Eddy Simulations are produced and analysed in the present document to investigate the flow behavior as well as the impact of the synthetic jets on wall heat transfer.
The experimental system considered here consists in a perforated heated plate, each perforation being above a cavity where a piston is used to control the synthetic jets. Placed in a wind tunnel test section, the device can be studied with a grazing flow and multiple operating points are available. The one considered here implies a grazing flow velocity of 12.8 m.sâˆ’1, corresponding to a Mach number around 0.04, and a piston displacement of 22 mm peak-to-peak at a frequency of 12.8 Hz. These two latter parameters lead to a jet Reynolds number of about 830.
A good agreement is found between numerical results and experimental data. The simulations are then used to provide a detailed understanding of the flow. Two main behaviours are found, depending on the considered mid-period. During the ejection phase, the flow transitions to turbulence and the formation of characteristic structures is observed; the plate is efficiently cooled. During the suction phase the main flow is stabilised; the heat enhancement is particularly efficient in the hole wakes but not between them, leading to a heterogeneous temperature field.},
keywords = { Large Eddy Simulations, Heat transfer, Synthetic jets}}

Odier, N., Poinsot, T., Duchaine, F., Gicquel, L.Y.M. and Moreau, S. (2019) Inlet and outlet characteristics boundary conditions for Large Eddy Simulations of turbomachinery, Proceedings of the ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition. ASME, Phoenix, USA, 6 2019, doi: 10.1115/GT2019-90747

[bibtex]

@CONFERENCE{PR-CFD-19-126,
author = {Odier, N. and Poinsot, T. and Duchaine, F. and Gicquel, L.Y.M. and Moreau, S. },
title = {Inlet and outlet characteristics boundary conditions for Large Eddy Simulations of turbomachinery},
year = {2019},
month = {6},
booktitle = {Proceedings of the ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition},
volume = {2 C},
number = {GT2019-90747},
pages = {1-11},
organization = {ASME},
address = {Phoenix, USA},
doi = {10.1115/GT2019-90747}}

Cuenot, B., Poinsot, T., Gicquel, L.Y.M., Vermorel, O., Duchaine, F., Riber, E., Dauptain, A., Staffelbach, G., Dombard, J., Misdariis, A. and Lapeyre, C. (2019) Large Eddy Simulation of turbulent reacting flows : methods and applications - Invited plenary lecture, 17th International Conference on Numerical Combustion. German section of the Combustion Institute, Aachen (Germany, 5 2019

[bibtex] [pdf]

@CONFERENCE{PR-CFD-19-164,
author = {Cuenot, B. and Poinsot, T. and Gicquel, L.Y.M. and Vermorel, O. and Duchaine, F. and Riber, E. and Dauptain, A. and Staffelbach, G. and Dombard, J. and Misdariis, A. and Lapeyre, C. },
title = {Large Eddy Simulation of turbulent reacting flows : methods and applications - Invited plenary lecture},
year = {2019},
month = {5},
booktitle = {17th International Conference on Numerical Combustion},
organization = { German section of the Combustion Institute},
address = {Aachen (Germany},
keywords = {combustion},
pdf = {https://cerfacs.fr/wp-content/uploads/2021/01/ICNC2019-Cuenot.pdf}}

Duchaine, F., Segui-Troth, L., de Laborderie, J., Odier, N., Dombard, J. and Gicquel, L.Y.M. (2019) Large-Eddy Simulations of turbomachinery flows: from wall-resolved academic configurations to wall-modeled industrial geometries, 72nd Annual Meeting of the APS Division of Fluid Dynamics., Seattle, Washington (USA), 11 2019

[bibtex]
[url]

@CONFERENCE{PR-CFD-19-189,
author = {Duchaine, F. and Segui-Troth, L. and de Laborderie, J. and Odier, N. and Dombard, J. and Gicquel, L.Y.M. },
title = {Large-Eddy Simulations of turbomachinery flows: from wall-resolved academic configurations to wall-modeled industrial geometries},
year = {2019},
month = {11},
booktitle = {72nd Annual Meeting of the APS Division of Fluid Dynamics},
volume = {64},
number = {13},
address = {Seattle, Washington (USA)},
abstract = {LES has been shown to be a promising tool to tackle turbomachinery challenges induced by high Reynolds and Mach numbers and complex flow physics. The CPU cost is however identified as the reason why existing LES of turbomachinery flows concern simplified configurations. CERFACS has extended the capability of the reactive LES solver AVBP for turbomachinery applications. The developments and validations have concerned the application of accurate boundary conditions at inlets and outlets as well as the numerical treatment of the rotor/stator interface compliant with LES requirements.
After a brief description of the flow solver, the presentation will focus on the results and insights obtained on two configurations. The first one is the high-pressure turbine cascade LS89 for which the MUR239 operating point is still today a challenge to simulate accurately. To address this academic aerothermal case, a wall-resolved approach is used with a high-order numerical scheme. The second configuration of interest is the 3.5 stages high-pressure axial compressor CREATE. This simulation, corresponding to one of the first wall-modeled LES of such a complex machine, has shown very promising results by comparison with experimental data.},
keywords = {LES, TURBOMACHINARY},
url = {https://meetings.aps.org/Meeting/DFD19/Content/3770}}

Harnieh, M., Gicquel, L.Y.M. and Duchaine, F. (2018) Large eddy simulations of a highly loaded transonic blade with separated flow - Invited conference, Turbomachinery Technical Conference & Exposition 2018. ASME International Gas Turbine Institute, Oslo, Norway, 6 2018

[bibtex]

@CONFERENCE{PR-CFD-18-84,
author = {Harnieh, M. and Gicquel, L.Y.M. and Duchaine, F. },
title = {Large eddy simulations of a highly loaded transonic blade with separated flow - Invited conference},
year = {2018},
month = {6},
booktitle = {Turbomachinery Technical Conference & Exposition 2018},
pages = {GT2018-75730},
organization = {ASME International Gas Turbine Institute},
address = {Oslo, Norway},
abstract = {Efficient design of highly loaded pressure blades often leads to the generation of a separation bubble on the pressure side of highly curved blades. For this specific region, fundamental, numerical and experimental studies have indicated the importance of the turbulence present in the main stream in determining the size of the bubble before its reattachment to the blade. Despite this important finding, many complex phenomena remain and are still present and can influence the overall flow response. In this paper, explorations of high-fidelity unsteady Large Eddy Simulations of a separated flow are studied for the high pressure T120 blade from the European project AITEB II (Aerothermal Investigation on Turbine Endwalls and Blades). For this investigation, simulations are carried out at the nominal operating point with and without synthetic turbulence injection at the inlet condition to comply with the specification from the experiment. Based on these predictions, the near wall
flow structure and turbulent fields are specifically investigated in an attempt to identify the key mechanisms introduced by the turbulent main stream
flow. Results show that the turbulence specification at the inlet enables the recovery of the correct pressure distribution on the blade surface contrary to the laminar inlet condition if compared to the experiment. Investigations of the boundary layer profiles show a strong impact of the freestream turbulence on the shape factor from the leading edge. As a consequence, the recirculation bubble located downstream on the pressure side is impacted and reduced when turbulence is injected. Due to this change in mean flow topology, the mass flow distribution in the passage appears strongly affected. Investigations of loss fields furthermore show that the freestream turbulence dramatically increases the loss production within the computational domain.},
keywords = {LES, Detached flow, loss}}

Harnieh, M., Thomas, M., Bizzari, R., Gicquel, L.Y.M. and Duchaine, F. (2018) Assessment of a coolant injection model on cooled high-pressure vanes in Large Eddy Simulation - Invited conference, 12th International Symposium on Engineering Turbulence Modelling and Measurements (ETMM12)., Montpellier, France, 9 2018, ERCOFTAC

[bibtex] [pdf]

@CONFERENCE{PR-CFD-18-86,
author = {Harnieh, M. and Thomas, M. and Bizzari, R. and Gicquel, L.Y.M. and Duchaine, F. },
title = {Assessment of a coolant injection model on cooled high-pressure vanes in Large Eddy Simulation - Invited conference},
year = {2018},
month = {9},
booktitle = {12th International Symposium on Engineering Turbulence Modelling and Measurements (ETMM12)},
editor = {ERCOFTAC},
address = {Montpellier, France},
abstract = {Combustion temperatures in modern gas turbine engines reach levels well above the thermal stress limit of materials. Being the most critical component of the engine, the high-pressure turbine blades are therefore equipped with cooling system to ensuresafe and longterm operation. To predict the flow in such configurations, Reynolds Average Navier Stokes (RANS) is usually used in the industrial context but is limited by its steady formalism. Potential improvement is foreseen with the Large Eddy Simulation (LES) which resolves the most energetic turbulent structures while modeling the small ones and has been found to be well suited to predict turbulent and fully unsteady flows. However, assessing the impact of a cooling system on the flow field of the high-pressure turbine using high fidelity simulations still remains prohibitively expensive. This work investigates the applicability for turbine cooled blades of a recently proposed effusion cooling model, designed for modeling c
ooling of the combustion chamber liners. This model was specifically designed to mimic the impact of cooling jets and do not require to solve the flow in the liners which leads to a dramatic reduction of the CPU cost. To assess the applicability of the model on turbine blades, the cooled NGVs of the FACTOR configuration are chosen. A modeled LES using the hole model is carried out and compared to a hole-resolved LES on the same configuration. Results show that both simulations give very close results. The time averaged skin temperature of the model LES is slightly lower than the resolved one. Indeed, the cold film around the NGVs is colder and thinner with the model. Indeed, investigation of the RMS fields also shows that the turbulent mixing is less important if applied the model to blades.},
keywords = {LES, Modeling hole, Cooling},
pdf = {https://cerfacs.fr/wp-content/uploads/2018/07/CFD_HARNIEH_ETMM12.pdf}}

Thomas, M., Duchaine, F., Gicquel, L.Y.M. and Koupper, C. (2018) Impact of realistic inlet condition on les predictions of isolated high pressure vanes, 12th International ERCOFTAC Symposium on Engineering Turbulence Modelling and Measurements (ETMM12) ., Montpellier, France, 9 2018

[bibtex]

@CONFERENCE{PR-CFD-18-113,
author = {Thomas, M. and Duchaine, F. and Gicquel, L.Y.M. and Koupper, C. },
title = {Impact of realistic inlet condition on les predictions of isolated high pressure vanes},
year = {2018},
month = {9},
booktitle = {12th International ERCOFTAC Symposium on Engineering Turbulence Modelling and Measurements (ETMM12) },
address = {Montpellier, France},
abstract = {Next generation lean combustion gas turbine engines
feature a harsher aerothermal environment if
compared to current state of the art engine technologies.
Higher levels of swirl, turbulence and temperature
non-uniformities at the exit of the combustion
chamber directly impact the high-pressure turbine,
which in industrial design practice is usually simulated
separately using 1D time averaged profiles as
inlet condition for the turbine. The definition of inlet
boundary conditions for stand-alone high fidelity
stator simulations is however crucial to obtain meaningful
Large Eddy Simulation (LES) predictions and
1D time averaged profiles are most likely inappropriate.
This work investigates this specific point and compares
different approaches. To do so, an integrated
simulation of a combustion chamber and its high pressure
vanes is performed first and serves as a reference
for stand-alone stator vane simulations performed
afterwards using inlet boundary conditions retrieved
from the first simulation. As shown hereafter use of
instantaneous flow fields from the reference simulation
allows to a large extent to recover the correct
flow field, which is a huge improvement over simulations
using 2D constant boundary conditions, with or
without synthetic turbulence. Differences between
the fully integrated simulation and that using constant
boundary conditions are principally due to the lack
of mixing and strong persistent vortex structures in
the stand-alone high pressure turbine simulation using
constant boundary conditions. Changes of secondary
flow patterns are also seen to impact the temperature
distribution on the nozzle guide vane (NGV) walls.},
keywords = {LES, combustor-turbine interface}}

Odier, N., Duchaine, F., Gicquel, L.Y.M., Staffelbach, G., Thacker, A., Garcia-Rosa, N., Dufour, G. and Mueller, J.-D. (2018) Evaluation of Integral Turbulence Scale Through the Fan Stage of a Turbofan Using Hot Wire Anemometry and Large Eddy Simulation, ASME Turbo Expo 2018: Turbomachinery Technical Conference & Exposition. ASME, Oslo, Norwa, 6 2018, doi: 10.1115/GT2018-75741

[bibtex]
[url]

@CONFERENCE{PR-CFD-18-118,
author = {Odier, N. and Duchaine, F. and Gicquel, L.Y.M. and Staffelbach, G. and Thacker, A. and Garcia-Rosa, N. and Dufour, G. and Mueller, J.-D. },
title = {Evaluation of Integral Turbulence Scale Through the Fan Stage of a Turbofan Using Hot Wire Anemometry and Large Eddy Simulation},
year = {2018},
month = {6},
booktitle = {ASME Turbo Expo 2018: Turbomachinery Technical Conference & Exposition},
volume = {Volume 2C},
number = {GT2018-75741},
pages = {pp. V02CT42A021},
organization = {ASME},
address = {Oslo, Norwa},
doi = {10.1115/GT2018-75741},
abstract = {This paper aims at evaluating wall-modeled LES capabilities to accurately predict turbulence properties in an aero-engine turbomachinery configuration. To do so, two LES numerical setups are compared, the first one using a 2nd-order space and time numerical scheme on a user-defined mesh, the second one using a 3rd order accurate in space and 4th order time numerical scheme on an automatically adapted mesh. Numerical results are compared to hot-wire anemometry measurements. Turbulence is evaluated through a triple velocity decomposition, enabling the evaluation of stochastic velocity fluctuations. A very fair agreement is evidenced regarding the numerically predicted turbulence spectra and integral turbulence time scale. Turbu- lence intensity values is however over estimated downstream of the stator, underlying the need for a second mesh adaptation.},
keywords = {Turbomachinery},
url = {http://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleID=2700717}}

Dombard, J., Duchaine, F., Gicquel, L.Y.M., Staffelbach, G., Buffaz, N. and Trebinjac, I. (2018) Large Eddy Simulations in a transonic centrifugal compressor, Proceedings of ASME Turbo Expo 2018: Turbine Technical Conference and Exposition. International Gas Turbine Institute, Oslo, Norway, 6 2018, doi: 10.1115/GT2018-77023

[bibtex]
[url]

@CONFERENCE{PR-CFD-18-185,
author = {Dombard, J. and Duchaine, F. and Gicquel, L.Y.M. and Staffelbach, G. and Buffaz, N. and Trebinjac, I. },
title = {Large Eddy Simulations in a transonic centrifugal compressor},
year = {2018},
month = {6},
booktitle = {Proceedings of ASME Turbo Expo 2018: Turbine Technical Conference and Exposition},
volume = {Volume 2B},
number = {GT2018-77023},
pages = { V02BT44A030 - 10 pages},
organization = {International Gas Turbine Institute},
address = {Oslo, Norway},
doi = {10.1115/GT2018-77023},
abstract = {In an attempt to validate a Large Eddy Simulation (LES) approach, computations of a transonic centrifugal compressor with a backswept, unshrouded impeller followed by radial and axial vaned diffusers are performed. A sector composed of one main
blade and one splitter blade, two radial diffuser vanes and six axial diffuser vanes is simulated including all the technological effects of the experimental rig. The LES methodology to simulate the rotor/stator configuration is introduced. Emphasis is put on the best trade-off between accuracy of the simulation and affordable CPU cost. A law-of-the-wall boundary condition is used to reduce the mesh size, with a target of y+ around a hundred for all walls except in the tip leakage with y+ around five. Computation of one entire characteristic line is obtained continuously in time: the transient from the flow at rest to the converged points at blockage, peak efficiency, near surge and path to deep surge is computed increasing progressively the outlet pressure as in the experiments. First, LES results are compared to experiments and show excellent agreement both in
terms of overall performance and time-averaged internal flow fields previously obtained by Laser Doppler Anemometry. Then, a focus is proposed on the complementary information LES provide in the rotor. The key findings are that contrary to previous URANS studies in this centrifugal compressor, LES capture influential details of the flow structures in the rotor: secondary structures, shock/boundary layer interaction and boundary layer separation at the tip of the impeller. Moreover, it is clearly shown that the tip leakage vortex increases in size and intensity from peak efficiency to surge and becomes much more erratic. Emphasis is put on the causes and consequences of the tip leakage spillage in the neighbouring rotor channels. Pressure fluctuations were also found to increase from peak efficiency to surge downstream the splitter blade leading edge. The whole results finally show that LES with a law-ofthe-wall provides excellent results in such a complex case.},
keywords = {Turbomachinery, Compressors , Large eddy simulation},
url = {http://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleid=2700695}}

Bizzari, R., Lahbib, D., Dauptain, A., Duchaine, F., Richard, S. and Nicoud, F. (2018) A model able to assess multiperforated liners temperature from an unresolved adiabatic simulation, Journée SFT - Groupes "Convection" et "Modélisation et Simulation Numérique"., Paris, France, 3 2018, Société Française de Thermique

[bibtex] [pdf]

@CONFERENCE{PR-CFD-18-211,
author = {Bizzari, R. and Lahbib, D. and Dauptain, A. and Duchaine, F. and Richard, S. and Nicoud, F. },
title = {A model able to assess multiperforated liners temperature from an unresolved adiabatic simulation},
year = {2018},
month = {3},
booktitle = {Journée SFT - Groupes "Convection" et "Modélisation et Simulation Numérique"},
editor = {Société Française de Thermique},
address = {Paris, France},
abstract = {A low-order model is proposed to predict the temperature of a multi-perforated plate
from an unresolved adiabatic computation. Its development relies on the analysis of both
an adiabatic and a conjugate heat transfer wall resolved large eddy simulation of an academic multi-perforated liner representative of the cooling systems used in combustion
chambers of actual aero-engines. These two simulations show that the time averaged
velocity field is marginally modified by the coupling with the heat diffusion in the perforated plate when compared to the adiabatic case. This gives rise to a methodology to
assess the wall temperature from an unresolved adiabatic computation. It relies on heat
transfer coefficients from referenced correlations as well as a mixing temperature relevant
to the flow in the injection region where the cold micro-jets mix with the hot outer flow.
In this approach, a coarse mesh simulation using an homogeneous adiabatic model for
the aerodynamics of the flow with effusion is post-processed to provide a low cost alternative to conjugate heat transfer computations based on hole resolved meshes. The
model is validated on an academic test case and successfully applied to a real industrial
combustion chamber.},
keywords = {couplage thermique, numérique},
pdf = {https://cerfacs.fr/wp-content/uploads/2018/12/Abstract_SFT.pdf}}

Brunet, V., Croner, E., Minot, A., de Laborderie, J., Lippinois, E., Richard, S., Boussuge, J.-F., Dombard, J., Duchaine, F., Gicquel, L.Y.M., Poinsot, T., Puigt, G., Staffelbach, G., Segui-Troth, L., Vermorel, O., Villedieu, N., Cagnone, J.-S., Hillewaert, K., Rasquin, M., Lartigue, G., Moureau, V., Couaillier, V., Martin, E., de la Llave Plata, M., Le Gouez, J.-M. and Renac, F. (2018) Comparison of Various CFD Codes for LES Simulations of Turbomachinery: From Inviscid Vortex Convection to Multi-Stage Compressor, ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition., Oslo (Norway), 6 2018, doi: 10.1115/GT2018-75523

[bibtex]
[url]

@CONFERENCE{PR-CFD-18-225,
author = {Brunet, V. and Croner, E. and Minot, A. and de Laborderie, J. and Lippinois, E. and Richard, S. and Boussuge, J.-F. and Dombard, J. and Duchaine, F. and Gicquel, L.Y.M. and Poinsot, T. and Puigt, G. and Staffelbach, G. and Segui-Troth, L. and Vermorel, O. and Villedieu, N. and Cagnone, J.-S. and Hillewaert, K. and Rasquin, M. and Lartigue, G. and Moureau, V. and Couaillier, V. and Martin, E. and de la Llave Plata, M. and Le Gouez, J.-M. and Renac, F. },
title = {Comparison of Various CFD Codes for LES Simulations of Turbomachinery: From Inviscid Vortex Convection to Multi-Stage Compressor},
year = {2018},
month = {6},
booktitle = {ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition},
volume = {2C},
number = {GT2018-75523},
pages = {V02CT42A013},
address = {Oslo (Norway)},
doi = {10.1115/GT2018-75523},
abstract = {Some possible future High Fidelity CFD codes for LES simulation of turbomachinery are compared on several test cases increasing in complexity, starting from a very simple inviscid Vortex Convection to a multistage axial experimental compressor. Simulations were performed between 2013 and 2016 by major Safran partners (Cenaero, Cerfacs, CORIA and Onera) and various numerical methods compared: Finite Volume, Discontinuous Galerkin, Spectral Differences. Comparison to analytical results, to experimental data or to RANS simulations are performed to check and measure accuracy. CPU efficiency versus accuracy are also presented. It clearly appears that the level of maturity could be different between codes and numerical approaches. In the end, advantages and disadvantages of every codes obtained during this project are presented.},
keywords = { Compressors , Simulation , Computational fluid dynamics , Convection , Vortices , Turbomachinery},
url = {http://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleid=2700709}}

Aillaud, P., Duchaine, F., Gicquel, L.Y.M. and Didorally, S. (2017) Characterization of the surface curvature effect using LES for a single round impinging jet, Proceedings of ASME Turbo Expo 2017: Turbine Technical Conference and Exposition ., Charlotte, NC, USA 2017

[bibtex]

@CONFERENCE{PR-CFD-17-43,
author = {Aillaud, P. and Duchaine, F. and Gicquel, L.Y.M. and Didorally, S. },
title = {Characterization of the surface curvature effect using LES for a single round impinging jet},
year = {2017},
booktitle = {Proceedings of ASME Turbo Expo 2017: Turbine Technical Conference and Exposition },
pages = {GT2017-64159},
address = {Charlotte, NC, USA},
abstract = {In this paper, wall resolved Large Eddy Simulation is used to study the effect of the surface curvature for two impinging jet configurations. The reference case is a single round jet imping- ing on a flat plate at a Reynolds number (based on the bulk ve- locity Ub and the pipe diameter D) Re = 23 000 and for a nozzle to plate distance H = 2D. The results on this configuration have been previously analyzed and validated against experimental re- sults. This paper compares for the same operating point, the flat plate impingement to an impinging jet on a concave hemi- spherical surface with a relative curvature d/D = 0.089 where d is the concave surface diameter. Mean and Root Mean Square (RMS) quantities are compared to highlight differences and sim- ilarities between the two cases. In addition high order statistic such as Skewness of the temporal distribution of wall heat flux is analyzed. Probability density functions (PDF) are also built to further characterize the effect of surface curvature. It is shown that the surface curvature has a destabilizing effect on the vorti- cal structures present in such a flow leading to a modification of the wall heat transfer compared to the flat plate case. The flow topology in the concave case is dominated by a large toroidal stationary vortex. This vortex generates a natural confinement that causes the increase of the mean temperature of the ambient air around the jet. The main effect is the reduction of the capac- ity of the vortical structures to enhance heat transfer. Finally, the confinement effect combined with the destabilization due to the concave curvature lead to an alleviation of the secondary peak in the Nusselt distribution and a reduction of the heat transfer at the wall
}}

Odier, N., Duchaine, F., Gicquel, L.Y.M., Dufour, G. and Garcia-Rosa, N. (2017) Comparison of LES and RANS predictions with experimental results of the fan of a turbofan, Proceedings of 12th European Conference on Turbomachinery Fluid dynamics & Thermodynamics., Stockholm, Sweden 2017

[bibtex] [pdf]

@CONFERENCE{PR-CFD-17-57,
author = {Odier, N. and Duchaine, F. and Gicquel, L.Y.M. and Dufour, G. and Garcia-Rosa, N. },
title = {Comparison of LES and RANS predictions with experimental results of the fan of a turbofan},
year = {2017},
booktitle = {Proceedings of 12th European Conference on Turbomachinery Fluid dynamics & Thermodynamics},
number = {Paper ID: ETC2017-126},
address = {Stockholm, Sweden},
abstract = {This paper aims at validating LES capability if applied to an actual turbofan configuration
at nominal regime, if compared to RANS and experimental measurements. For
assessment, averaged radial profiles are compared in 3 axial planes – before the stage,
between the rotor blade and stator vanes, and downstream of the stator. RANS and LES
results are in very good agreement, but found to be shifted compared to the measurements
and for some quantities. An analysis of the unsteady axial velocity is then proposed, investigating
root-mean square of axial velocity. Tip-leakage, as well as two boundary layer
transitions are evidenced in the rotor. An estimation of the integral turbulent timescale is
finally proposed in the whole domain, using autocorrelation of the axial velocity. Suctionside
horseshoe vortices are found to be very coherent, as well as the stator corner vortices.
Regions of large timescale are moreover evidenced between rotor and stator wakes},
pdf = {https://cerfacs.fr/wp-content/uploads/2017/04/CFD_ETC2017_ODIER.pdf}}

Segui-Troth, L., Gicquel, L.Y.M., Duchaine, F. and de Laborderie, J. (2017) LES of the LS89 cascade: influence of inflow turbulence on the flow predictions, 12th European Conference on Turbomachinery Fluid Dynamics & Thermodynamics ., Stockholm, Sweden 2017, EUROTURBO

[bibtex] [pdf]

@CONFERENCE{PR-CFD-17-59,
author = {Segui-Troth, L. and Gicquel, L.Y.M. and Duchaine, F. and de Laborderie, J. },
title = {LES of the LS89 cascade: influence of inflow turbulence on the flow predictions},
year = {2017},
booktitle = { 12th European Conference on Turbomachinery Fluid Dynamics & Thermodynamics },
editor = {EUROTURBO},
pages = {Paper ID: ETC2017-159},
address = {Stockholm, Sweden},
abstract = {Free-stream turbulence preceding high-pressure turbine blades has a crucial impact on
blade fields including the heat transfer on the wall. Many parameters characterize this
turbulence; its intensity, length scales and physical spectrum are addressed in the study of
various operating points of the LS89 configuration. Usually, operating points where weak
turbulence is injected are well predicted for all fields by Direct Numerical Simulations
(DNS) and Large Eddy Simulations (LES). The MUR235 operating point however, with
an experimentally injected turbulence level of 6%, remains incorrectly predicted when imposing
the experimental values in the simulations. Such difficulties raise many questions
amongst which mesh size and turbulent kinetic energy spectrum are of specific importance
for LES. Going away from synthetic turbulence injection by imposing a physical energy
spectrum can help improving the prediction of heat transfer. From the present study, it
seems that turbulent spots developing in a pre-transition region for higher levels of turbulence
on the suction side are important features to capture for proper predictions. In
parallel, typical structures of boundary layers such as streamwise oriented vortices have
been observed and their existence conditions the heat transfer field on the blade wall.
From this specific study, all of these physical processes are seen to be highly dependent on
the turbulent specification and turbulent transition observed for the MUR235 case. Depending
on these inflow specifications, a transitional boundary layer may be encountered
upstream of the shock thus modifying the heat transfer profile.},
keywords = {Large Eddy Simulation, Combustion},
pdf = {https://cerfacs.fr/wp-content/uploads/2017/04/ETC2017-159_Segui.pdf}}

de Laborderie, J., Duchaine, F. and Gicquel, L.Y.M. (2017) Analysis of a high-pressure multistage axial compressor at off-design conditions with coarse Large Eddy Simulations, 12th European Conference on Turbomachinery Fluid Dynamics & Thermodynamics., Stockholm, Sweden 2017, EUROTURBO

[bibtex] [pdf]

@CONFERENCE{PR-CFD-17-60,
author = {de Laborderie, J. and Duchaine, F. and Gicquel, L.Y.M. },
title = {Analysis of a high-pressure multistage axial compressor at off-design conditions with coarse Large Eddy Simulations},
year = {2017},
booktitle = {12th European Conference on Turbomachinery Fluid Dynamics & Thermodynamics},
editor = {EUROTURBO},
pages = {Paper ID: ETC2017-125},
address = {Stockholm, Sweden},
abstract = {This paper aims at evaluating Large Eddy Simulations (LES) for the prediction of the performance line and flow at off-design conditions in a multistage high-pressure compressor. A coarse and an intermediate grid are specifically investigated, since their associated computational cost appears affordable in an industrial context. Several operating conditions of the 3.5 stages high-pressure compressor CREATE are simulated, then results are compared to experimental data and to an existing URANS simulation. Both grids yield iso-speed performance lines close to experimental measurements, but only the intermediate one is able to correctly predict the experimental point at lowest mass flow rate. The unstable regime is specifically investigated in the last stage of the intermediate grid, showing the presence of rotating instabilities. Their amount and spinning velocity are similar to experimental observations and previous URANS results. Hence coarse LES appears as an interesting tradeoff for off-design predictions of flow in a multistage compressor.},
keywords = {Large Eddy Simulation, Combustion},
pdf = {https://cerfacs.fr/wp-content/uploads/2017/04/ETC2017-125_JLaborderie.pdf}}

Harnieh, M., Gicquel, L.Y.M. and Duchaine, F. (2017) Sensitivity of Large Eddy Simulations to inflow condition and modeling if applied to a transonic high-pressure cascade vane, Proceedings of ASME Turbo Expo 2017: Turbine Technical Conference and Exposition., Charlotte, NC, USA 2017

[bibtex]

@CONFERENCE{PR-CFD-17-96,
author = {Harnieh, M. and Gicquel, L.Y.M. and Duchaine, F. },
title = {Sensitivity of Large Eddy Simulations to inflow condition and modeling if applied to a transonic high-pressure cascade vane},
year = {2017},
booktitle = {Proceedings of ASME Turbo Expo 2017: Turbine Technical Conference and Exposition},
pages = {paper GT2017-64686 },
address = {Charlotte, NC, USA},
abstract = {Large Eddy Simulation (LES) prediction of the flow around
transonic high-pressure turbine cascade vanes is an active subject
of research. For such problems, the flow topology is dictated
by the geometry, inflow conditions and irreversibilities. When
studied experimentally, input specifications necessarily suffer
from uncertainties inherent to experimental measurement facilities.
Such limits are also present in numerical applications. The
following paper proposes to evaluate the relative importance of
uncertainty sources in determining the adequate LES flow behaviour
for the T120 transonic blade experimentally tested at
UniBw (Munich) during the European project AITEB II. To do so,
the nominal operating point is targeted and different simulations
are obtained by changing inflow specifications with and without
turbulence injection. As expected, changes in the static pressure
ratio between the inlet and the outlet by more or less 4%, alter
significantly the flow topology and the aerodynamic losses.
Impact of turbulence injection at inlet is also addressed. Investigation
of dissipation fields, including the laminar and sub-grid
model contributions, allows the identification of the underlying
mechanisms. Although irreversibilities have a smaller impact on
the flow prediction relative to the static pressure ratio (and associated
uncertainties), its relevance on the flow prediction and
topology is found to be of primary importance.
}}

Aillaud, P., Duchaine, F., Gicquel, O., Koupper, C. and Staffelbach, G. (2017) Large Eddy Simulation of trailing edge cutback film cooling: Impact of internal stiffening ribs on the adiabatic effectiveness, 7th European Conference for Aeronautics and Aerospace Sciences (EUCASS 2017)., Milan, Italy 2017

[bibtex] [pdf]

@CONFERENCE{PR-CFD-17-109,
author = {Aillaud, P. and Duchaine, F. and Gicquel, O. and Koupper, C. and Staffelbach, G. },
title = {Large Eddy Simulation of trailing edge cutback film cooling: Impact of internal stiffening ribs on the adiabatic effectiveness},
year = {2017},
booktitle = {7th European Conference for Aeronautics and Aerospace Sciences (EUCASS 2017)},
volume = {CD},
address = {Milan, Italy},
abstract = {This study deals with the Large Eddy Simulation (LES) of the film cooling technique at the trailing edge of a transonic vane equipped with a pressure side cutback. This configuration was studied experimentally at DLR within the framework of the European project AITEB-2. The cooling air is blown through a long slot and two rib arrays are placed inside the coolant channel to increase the stiffness of the thin trailing edge region. The simulation is first validated against global quantities such as the discharge coeffcient and the blowing ratio as well as local quantities such as the isentropic Mach number and the adiabatic effectiveness.
Then LES results are used to connect the flow dynamics to the adiabatic effectiveness observed in the cutback region. The interesting point is that the spatial period of the adiabatic effectiveness patterns, observed experimentally and numerically, is not the separation distance S in the spanwise direction between two consecutive ribs but is approximately 4S . 3D flow visualizations highlight different physical phenomena present in the internal channel such as a separated flow at certain locations behind the diffuser array. It is shown that this separation is caused by a Coanda effect forcing the flow to follow the curvature of a profiled rib at some specific locations. This mechanism is used to explain the inhomogeneities observed
in the spanwise direction for the adiabatic effectiveness. The separation regions behind the diffuser array cause an early attachment of the main flow to the cutback surface, detected with the skin friction lines, causing a rapid decrease of the the adiabatic effectiveness. This non-uniform film, generated by such a diffuser array, may affect the thermal behavior of the trailing edge.},
pdf = {https://cerfacs.fr/wp-content/uploads/2017/07/Aillaud_et_al_eucass_2017.pdf}}

Thomas, M., Dauptain, A., Duchaine, F., Gicquel, L.Y.M., Koupper, C. and Nicoud, F. (2017) Comparison of Heterogeneous and Homogeneous Coolant Injection Models for Large Eddy Simulation of Multiperforated Liners Present in a Combustion Simulator, ASME Turbo Expo 2017 Proceedings : Design Methods and CFD Modeling for Turbomachinery. International Gas Turbine Institute, Charlotte, North Carolina, USA, 2017, doi: 10.1115/GT2017-64622

[bibtex]

@CONFERENCE{PR-CFD-17-127,
author = {Thomas, M. and Dauptain, A. and Duchaine, F. and Gicquel, L.Y.M. and Koupper, C. and Nicoud, F. },
title = {Comparison of Heterogeneous and Homogeneous Coolant Injection Models for Large Eddy Simulation of Multiperforated Liners Present in a Combustion Simulator},
year = {2017},
booktitle = {ASME Turbo Expo 2017 Proceedings : Design Methods and CFD Modeling for Turbomachinery},
volume = {2B: Turbomachinery},
pages = {GT2017-64622 (12pp.)},
isbn = {978-0-7918-5079-4},
organization = {International Gas Turbine Institute},
address = {Charlotte, North Carolina, USA,},
doi = {10.1115/GT2017-64622},
abstract = {With the goal of increasing the thermodynamic efficiency of aircraft engines, the temperature in the combustion chamber has risen to the point where the gas temperature is above the melting point of materials used in the chamber and cooling systems are mandatory. Today, most of the existing lean burn combustors rely on multiperforated liners to keep hot gases away from the walls. However, resolving all holes of the combustor in the CFD design phase remains beyond currently available computational resources, so the effusion cooling system is often modeled by homogeneously injecting air on the whole surface of the liner, especially in the context of Large Eddy Simulation (LES) based CFD. This paper investigates a novel approach to simulate the effect of jets emitted from discrete holes on the flow inside a combustion chamber. In this new modeling approach, jet diameters are treated to be resolvable by the grid while conserving the correct mass and momentum flow rate. LES are performed on the combustion simulator of the engine representative FACTOR test rig at two different operating points and compared to measurement data as well as previous simulations obtained using a homogeneous air injection modeling on liners. The new approach shows globally similar results as the well validated homogeneous injection model and is applicable on realistic industrial geometries at a negligible level of additional cost (+0.3%).},
supplementaryMaterial = { http://proceedings.asmedigitalcollection.asme.org/}}

Thomas, M., Duchaine, F., Gicquel, L.Y.M. and Koupper, C. (2017) Advanced Statistical Analysis Estimating the Heat Load Issued by Hot Streaks and Turbulence on a High-Pressure Vane in the Context of Adiabatic Large Eddy Simulations, ASME Turbo Expo 2017 Proceedings : Design Methods and CFD Modeling for Turbomachinery. International Gas Turbine Institute, Charlotte, North Carolina, USA, 2017, doi: 10.1115/GT2017-64648

[bibtex]

@CONFERENCE{PR-CFD-17-128,
author = {Thomas, M. and Duchaine, F. and Gicquel, L.Y.M. and Koupper, C. },
title = {Advanced Statistical Analysis Estimating the Heat Load Issued by Hot Streaks and Turbulence on a High-Pressure Vane in the Context of Adiabatic Large Eddy Simulations},
year = {2017},
booktitle = {ASME Turbo Expo 2017 Proceedings : Design Methods and CFD Modeling for Turbomachinery},
volume = {2B: Turbomachinery},
pages = {GT2017-64648 (12 pages)},
isbn = {978-0-7918-5079-4},
organization = {International Gas Turbine Institute},
address = {Charlotte, North Carolina, USA,},
doi = {10.1115/GT2017-64648},
abstract = { The next generation of lean combustion engines promises to further decrease environmental impact and cost of air traffic. Compared to the currently employed Rich Quench Lean (RQL) concept, the flow field at the exit of a lean combustion chamber is characterized by stronger variations of velocity as well as temperature and higher levels of turbulence. These specific features may have a substantial impact on the aerothermal performance of the high-pressure turbine and thereby on the efficiency of the entire engine. Indeed, high levels of turbulence in the Nozzle Guide Vane (NGV) passages locally impact the heat flux and result in globally over dimensioned cooling systems of the NGV. In this study, Large Eddy Simulations (LES) are performed on an engine representative lean combustion simulator geometry to investigate the evolution of turbulence and the migration of hot streaks through the high-pressure turbine. To investigate the impact of non-uniform stator inlet conditions on the estimated thermal stress on the NGVs, adiabatic LES predictions of the lean combustor NGV FACTOR configuration are analyzed through the use of high statistical moments of temperature and two point statistics for the assessment of turbulent quantities. Relations between temperature statistical features and turbulence are evidenced on planes through the NGV passage pointing to the role of mixing and large scale features along with marked wall temperatures that locally can largely differ from obtained mean values.
},
supplementaryMaterial = {http://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleid=2649653}}

Grosnickel, T., Duchaine, F., Gicquel, L.Y.M. and Koupper, C. (2017) Large Eddy Simulations of static and rotating ribbed channels in adiabatic and isothermal conditions, Proceedings of ASME Turbo Expo 2017: Turbine Technical Conference and Exposition. 2017, doi: 10.1115/GT2017-64241

[bibtex]

@CONFERENCE{PR-CFD-17-320,
author = {Grosnickel, T. and Duchaine, F. and Gicquel, L.Y.M. and Koupper, C. },
title = {Large Eddy Simulations of static and rotating ribbed channels in adiabatic and isothermal conditions},
year = {2017},
booktitle = {Proceedings of ASME Turbo Expo 2017: Turbine Technical Conference and Exposition},
number = {GT2017-64241},
pages = {12 pp.},
doi = {10.1115/GT2017-64241},
abstract = {In an attempt to better understand spatially developing rotating
cooling flows, the present study focuses on a computational
investigation of a straight, rotating rib roughened cooling
channel initially numerically studied by Fransen et al. [1]. The
configuration consists of a squared channel equipped with 8 rib
turbulators placed with an angle of 90 degrees with respect to
the flow direction. The rib pitch-to-height (p/h) ratio is 10 and
the height-to-hydraulic diameter (h=Dh) ratio is 0.1. The simulations
are based on a case where time resolved two-dimensional
Particle Image Velocimetry (PIV) measurements have been performed
at the Von Karman Institute (VKI) in a near gas turbine
operating condition: the Reynolds number (Re) and the rotation
number (Ro) are around 15000 and 0.38 respectively.
Adiabatic as well as anisothermal conditions have been investigated
to evaluate the impact of the wall temperature on the
flow, especially in the rotating configurations. Static as well
as both positive and negative rotating channels are compared
with experimental data. In each case, either an adiabatic or an
isothermal wall boundary condition can be computed. In this
work, Large Eddy Simulation (LES) results show that the high
fidelity CFD model manages very well the turbulence increase
(decrease) around the rib in destabilizing (stabilizing) rotation of the ribbed channels. Thanks to the full spatial and temporal description
produced by LES, the spatial development of secondary
flows are found to be at the origine of observed differences with
experimental measurements. Finally, the model is also able to reproduce
the differences induced by buoyancy on the flow topology
in the near rib region and resulting from an anisothermal
flow in rotation.},
keywords = {LES, GAS TURBINE}}

Berger, S., Richard, S., Duchaine, F. and Gicquel, L.Y.M. (2016) Variations of anchoring pattern of a bluff-body stabilized laminar premixed flame as a function of the wall temperature, ASME Turbo Expo 2016., Seoul, South Korea 2016

[bibtex]
[url]

@CONFERENCE{PR-CFD-16-29525,
author = {Berger, S. and Richard, S. and Duchaine, F. and Gicquel, L.Y.M. },
title = {Variations of anchoring pattern of a bluff-body stabilized laminar premixed flame as a function of the wall temperature},
year = {2016},
booktitle = {ASME Turbo Expo 2016},
pages = {GT2016-56473},
address = {Seoul, South Korea},
abstract = {Aircraft engine components are subject to hostile thermal
environments. The solid parts in the hot stages encounter very
high temperature levels and gradients that are critical for the engine lifespan. Combustion chamber walls in particular exhibit
very heterogeneous thermal fields. The prediction of this specific thermal field is a very complex task as it results from complex interactions between fresh gas injections, cooling flow repartitions, combustion, flame stabilization and thermal transfers to the solids. All these phenomena are tightly coupled and do not evolve linearly. Today, the design phase of a combustion chamber is strongly enhanced by the use of high fidelity computations such as Large Eddy Simulations (LES). However, thermal boundary conditions are rarely well known and are thus treated either as adiabatic or as approximated isothermal conditions. Such approximations on thermal boundary conditions can lead to several errors and inaccurate predictions of the combustion chamber flow field. With this in mind and to foresee the potential difficulties
of LES based Conjugate Heat Transfer (CHT) predictions,
the effect of the wall temperature on a laminar premixed flame
stabilization is numerically investigated in this paper for an academic configuration. The considered case consists of a square cylinder flame holder at a low Reynolds number for which several wall-resolved Direct Numerical Simulations are performed varying the bluff body wall thermal condition. In such a set-up, the reactive flow and the flame holder interact in a complex way underlying a strong impact of the wall temperature. For a baseline configuration where the wall temperature is fixed at 700K, the flow field is steady with a flame anchored close to the recirculation zone of the flame holder. As the wall temperature is decreased, the position of the stabilized flame moves further downstream. The flame remains steady until a threshold cold temperature is reached below which an instability appears. For solid temperatures above 700 K, the flame is seen to move further and further upstream. For very hot conditions, the flame even stabilizes ahead of the bluff body. The various flow solution
bifurcations as the flame stabilization evolves are detailed
in this paper. Heat flux repartition along the bluff body walls are
observed to be dictated by the flame stabilization process illustrating different mechanisms while integration of these fluxes on the whole flame holder surface confirms that various theoretical equilibrium states exist for this configuration. This suggests that computation of more realistic cases including thermal conduction in the bluff body solid part could lead to different converged results depending on the initial thermal state.
NOMENCLATURE
Symbols
y+ Non-dimensionnal distance to the
wall of the first cell
ut Friction velocity
t Wall friction
n viscosity},
url = {https://asmedigitalcollection.asme.org/GT/proceedings-abstract/GT2016/49798/V05BT17A004/239705}}

Lahbib, D., Dauptain, A., Duchaine, F. and Nicoud, F. (2016) Large-Eddy Simulation of conjugate heat transfer around a multi-perforated plate with deviation, ASME Turbo Expo 2016., Seoul, South Korea 2016

[bibtex]

@CONFERENCE{PR-CFD-16-29527,
author = {Lahbib, D. and Dauptain, A. and Duchaine, F. and Nicoud, F. },
title = {Large-Eddy Simulation of conjugate heat transfer around a multi-perforated plate with deviation},
year = {2016},
booktitle = {ASME Turbo Expo 2016},
pages = {GT2016-56442},
address = {Seoul, South Korea}}

de Laborderie, J., Duchaine, F., Vermorel, O., Gicquel, L.Y.M. and Moreau, S. (2016) Application of an overset grid method to the Large-Eddy Simulation of a high speed multistage axial compressor, ASME Turbo Expo 2016., Seoul, South Korea 2016

[bibtex]

@CONFERENCE{PR-CFD-16-29529,
author = {de Laborderie, J. and Duchaine, F. and Vermorel, O. and Gicquel, L.Y.M. and Moreau, S. },
title = {Application of an overset grid method to the Large-Eddy Simulation of a high speed multistage axial compressor},
year = {2016},
pages = {GT2016-56344},
address = {Seoul, South Korea},
booktitle = {ASME Turbo Expo 2016}}

Koupper, C., Bonneau, L., Gicquel, L.Y.M. and Duchaine, F. (2016) Large-Eddy Simulation of the combustor turbine interface: study of the potential and clocking effects, ASME Turbo Expo 2016. 2016

[bibtex]

@CONFERENCE{PR-CFD-16-29531,
author = {Koupper, C. and Bonneau, L. and Gicquel, L.Y.M. and Duchaine, F. },
title = {Large-Eddy Simulation of the combustor turbine interface: study of the potential and clocking effects},
year = {2016},
pages = {GT2016-56443},
booktitle = {ASME Turbo Expo 2016}}

Aillaud, P., Duchaine, F. and Gicquel, L.Y.M. (2016) Analyse aérothermique d'un jet circulaire impactant sur plaque plane à l'aide de la SGE, Congrés Français de Thermique 2016., Toulouse, France, 5 2016

[bibtex] [pdf]

@CONFERENCE{PR-CFD-16-29533,
author = {Aillaud, P. and Duchaine, F. and Gicquel, L.Y.M. },
title = {Analyse aérothermique d'un jet circulaire impactant sur plaque plane à l'aide de la SGE},
year = {2016},
month = {5},
booktitle = {Congrés Français de Thermique 2016},
address = {Toulouse, France},
abstract = {Ce papier présente l’étude d’une Simulations aux Grandes Echelles (SGE) aérothermique
d'un jet circulaire, de diamètre D, impactant sur une paroi plane. Le nombre de Reynolds est de 23 000
et la distance jet-plaque est H = 2D. Après validation, cette base de données numérique est analysée
dans le but d’aider à la compréhension de l’apparition du second pic dans la distribution radiale du
nombre de Nusselt. Pour ce faire, les séries temporelles de vitesse et de pression sont utilisées pour
construire les statistiques d’ordre élevé, telles que la Skewness et le Kurtosis. Ces statistiques sont alors
analysées conjointement aux densités de probabilité issues des s'éries temporelles de température afin de
caractériser l’aérothermique du jet impactant.},
pdf = {https://cerfacs.fr/wp-content/uploads/2016/08/Aillaud_SFT16.pdf}}

Berger, S., Duchaine, F. and Gicquel, L.Y.M. (2016) Influence des conditions aux limites thermiques sur la stabilisation d'une flamme laminaire prémélangée, Congrés Français de Thermique 2016., Toulouse, France, 5 2016

[bibtex]
[url] [pdf]

@CONFERENCE{PR-CFD-16-29535,
author = {Berger, S. and Duchaine, F. and Gicquel, L.Y.M. },
title = {Influence des conditions aux limites thermiques sur la stabilisation d'une flamme laminaire prémélangée},
year = {2016},
month = {5},
booktitle = {Congrés Français de Thermique 2016},
address = {Toulouse, France},
abstract = {Le motif de stabilisation d’une flamme laminaire pre-melangee pauvre sur un accroche
flamme de section carree positionne dans un canal 2D est analysee en fonction de la temperature du
barreau. Trois grandes familles de topologies sont identifiees : des flammes decrochees se stabilisent en
arriere du barreau pour les faibles temperatures de barreau, des flammes accroches aux parois laterales
du cylindre pour les temperatures intermediaires et une stabilisation de flamme en amont de l’accroche
flamme pour les temperatures plus elevees. Ces resultats montrent un comportement non monotone de
l’integrale du flux de chaleur sur les parois du cylindre en fonction de la temperature parietale, indiquant
3 valeurs de temperatures pouvant mener a un equilibre thermique du solide. Ces trois temperatures
correspondent aux trois topologies de stabilisation. Finalement, des simulations de transfert de chaleur
conjugue avec differentes valeurs de conductivite indiquent que deux regimes sont thermiquement
stables : le premier correspond a la famille des flammes decrochees et le second pour lequel le barreau
est plonge dans les gaz chauds avec une flamme stabilisee en amont.},
pdf = {https://cerfacs.fr/wp-content/uploads/2016/08/berger_sft2016.pdf},
url = {http://www.sft.asso.fr/Local/sft/dir/user-3775/documents/actes/Congres_2016/resumes_toulouse/6.pdf}}

Léonard, T., Sanjosé, M., Moreau, S. and Duchaine, F. (2016) Large Eddy Simulation of a scale-model turbofan for fan noise source diagnostic, 22nd AIAA/CEAS Aeroacoustics Conference., Lyon, France 2016

[bibtex]
[url]

@CONFERENCE{PR-CFD-16-29539,
author = {Léonard, T. and Sanjosé, M. and Moreau, S. and Duchaine, F. },
title = {Large Eddy Simulation of a scale-model turbofan for fan noise source diagnostic},
year = {2016},
booktitle = {22nd AIAA/CEAS Aeroacoustics Conference},
pages = {AIAA 2016-3000},
address = {Lyon, France},
url = {http://dx.doi.org/10.2514/6.2016-3000}}

Errera, M.-P. and Duchaine, F. (2016) Stable and fast numerical schemes for conjugate heat transfer, ICHMT International Symposium on Advances in Computational Heat Transfer., Rutgers University, Piscataway, USA 2016

[bibtex]

@CONFERENCE{PR-CFD-16-29541,
author = {Errera, M.-P. and Duchaine, F. },
title = {Stable and fast numerical schemes for conjugate heat transfer},
year = {2016},
address = {Rutgers University, Piscataway, USA},
booktitle = {ICHMT International Symposium on Advances in Computational Heat Transfer}}

Aillaud, P., Duchaine, F. and Gicquel, L.Y.M. (2016) LES of a round impinging jet: investigation of the link between nusselt secondary peak and near-wall vortical structures, Proceedings of ASME Turbo Expo 2016: Turbine Technical Conference and Exposition., Seoul, South Korea 2016

[bibtex]

@CONFERENCE{PR-CFD-16-210,
author = {Aillaud, P. and Duchaine, F. and Gicquel, L.Y.M. },
title = {LES of a round impinging jet: investigation of the link between nusselt secondary peak and near-wall vortical structures},
year = {2016},
booktitle = {Proceedings of ASME Turbo Expo 2016: Turbine Technical Conference and Exposition},
number = {GT2016-56111},
address = {Seoul, South Korea},
abstract = {In an attempt to improve our understanding of the fundamental
flow problem that is an impinging jet, a wall-resolved
Large Eddy Simulation (LES) is produced to investigate largescale
unsteady flow features, mixing processes near the wall and
heat transfer. The simulation focuses on a single unconfined
round jet normally impinging on a flat plate at a Reynolds number
(based on the pipe diameter and bulk velocity) of Re = 23
000 and for a nozzle to plate distance of H = 2D. This configuration
is known to lead to a double peak in the Nusselt distribution.
Evaluation of the high order statistics, such as Skewness
and Kurtosis of the temporal evolution of axial velocity and wall
heat flux, provides first-ever insights into the effect of the vortical
structures on the mean wall heat transfer. Heat transfer statistics
such as probability density functions (PDF) confirm the ability
of LES to reproduce the strong intermittent thermal events responsible
for the increase of the mean wall heat transfer radial
distribution. Axial velocity and temperature temporal distributions
are analysed simultaneously to gain further insight into the
mixing process near the wall. In particular, the probabilities of
the different cold/hot fluid ejection/injection events prove that the
strong intermittent thermal events are linked to a change in the
mixing behavior induced by the passage of the large-scale vortical
structures. These structures are found to preferentially produce
a cold fluid flux towards the wall leading to the local heat
transfer enhancement usually identified by the secondary peak.}}

Duchaine, F., Berger, S., Staffelbach, G. and Gicquel, L.Y.M. (2016) Partitioned High Performance Coupling Applied to CFD, JARA HPC Symposium. Jülich Aachen Research Alliance (JARA), October 4-5, Aachen, Germany 2016

[bibtex]
[url] [pdf]

@CONFERENCE{PR-CMGC-16-230,
author = {Duchaine, F. and Berger, S. and Staffelbach, G. and Gicquel, L.Y.M. },
title = {Partitioned High Performance Coupling Applied to CFD},
year = {2016},
booktitle = {JARA HPC Symposium},
organization = {Jülich Aachen Research Alliance (JARA), October 4-5},
address = {Aachen, Germany},
keywords = {invite},
pdf = {https://cerfacs.fr/wp-content/uploads/2016/10/GLOBC-CONFERENCE-Duchaine-2016_JHPCS.pdf},
url = {http://hpc-symposium.jara.org}}

Ghani, A., Brebion, M., Selle, L., Duchaine, F. and Poinsot, T. (2016) Effect of wall heat transfer on screech in a turbulent premixed combustor, Proceedings of the Summer Program 2016. Center for Turbulence Research, Stanford University, Palo Alto, USA 2016

[bibtex] [pdf]

@CONFERENCE{PR-CFD-16-350,
author = {Ghani, A. and Brebion, M. and Selle, L. and Duchaine, F. and Poinsot, T. },
title = {Effect of wall heat transfer on screech in a turbulent premixed combustor},
year = {2016},
booktitle = {Proceedings of the Summer Program 2016},
pages = {133 - 142},
organization = {Center for Turbulence Research},
address = {Stanford University, Palo Alto, USA},
abstract = {Large eddy simulation (LES) of adiabatic and thermally coupled walls are compared for
a turbulent bluff-body flame which exhibits a strong unstable transverse mode called
screech. The flame is stabilized behind a triangular flame holder. LES captures the highfrequency
mode, but results depend on the condition used for heat transfer on the flame holder. Going from an adiabatic simulation to a thermally coupled case shifts the LES instability frequency: conjugate heat transfer (CHT) also modifies the limit-cycle amplitude: a decrease of 30% of the maximal amplitude is found compared to the adiabatic LES. An active control methodology is applied to control the mode and trigger it in order to study growth rates. In the linear regime, CHT results have growth rates which are half of those obtained for the adiabatic LES. This study shows the effect of wall temperature
on flame dynamics and the importance of wall temperatures for LES of combustion instabilities.},
pdf = {https://cerfacs.fr/wp-content/uploads/2017/01/CFD_CTR2016_Ghani.pdf}}

Berger, S., Richard, S., Staffelbach, G., Duchaine, F. and Gicquel, L.Y.M. (2015) Aerothermal prediction of an aeronautical combustion chamber based on the coupling of Large Eddy Simulation, solid conduction and radiation solvers, 15th International Conference on Numerical Combustion., Avignon, France, 4 2015

[bibtex]

@CONFERENCE{PR-CFD-15-23165,
author = {Berger, S. and Richard, S. and Staffelbach, G. and Duchaine, F. and Gicquel, L.Y.M. },
title = {Aerothermal prediction of an aeronautical combustion chamber based on the coupling of Large Eddy Simulation, solid conduction and radiation solvers},
year = {2015},
month = {4},
booktitle = {15th International Conference on Numerical Combustion},
address = {Avignon, France}}

Koupper, C., Bacci, T., Facchini, B., Picchi, A., Tarchi, L., Gicquel, L., Duchaine, F. and Bonneau, G. (2015) Experimental and numerical calculation of turbulent timescales at the exit of an engine representative combustor simulator, ASME Turbo Expo 2015: turbine technical conference and exposition. International Gas Turbine Institute, Montreal, Canada, 6 2015

[bibtex]
[url]

@CONFERENCE{PR-CFD-15-23372,
author = {Koupper, C. and Bacci, T. and Facchini, B. and Picchi, A. and Tarchi, L. and Gicquel, L. and Duchaine, F. and Bonneau, G. },
title = {Experimental and numerical calculation of turbulent timescales at the exit of an engine representative combustor simulator},
year = {2015},
month = {6},
booktitle = {ASME Turbo Expo 2015: turbine technical conference and exposition},
volume = {5C: Heat Transfer},
number = {GT2015-42278},
pages = {V05CT17A003},
isbn = {978-0-7918-5673-4},
organization = {International Gas Turbine Institute},
address = {Montreal, Canada},
abstract = {To deepen the knowledge of the interaction between modern lean burn combustors and high pressure turbines, a non-reactive real scale annular trisector Combustor Simulator (CS) has been assembled at University of Florence, with the goal of investigating and characterizing the combustor aerothermal field as well as the hot streak transport towards the high pressure vanes. To generate hot streaks and simulate lean burn combustor behaviors, the rig is equipped with axial swirlers fed by a main air flow stream that is heated up to 531 K, while liners with effusion cooling holes are fed by air at ambient temperature. Detailed experimental investigations are then performed with the aim of characterizing the turbulence quantities at the exit of the combustion module, and specifically evaluating an integral scale of turbulence. To do so, an automatic traverse system is mounted at the exit of the CS and equipped to perform Hot Wire Anemometry (HWA) measurements. In this paper, two-point correlations are computed from the time signal of the axial velocity giving access to an evaluation of the turbulence timescales at each measurement point. For assessment of the advanced numerical method that is Large Eddy Simulation (LES), the same methodology is applied to a LES prediction of the CS. Although comparisons seem relevant and easily accessible, both approaches and contexts have fundamental differences: mostly in terms of duration of the signals acquired experimentally and numerically but also with potentially different acquisition frequencies. In the exercise that aims at comparing high-order statistics and diagnostics, the specificity of comparing experimental and numerical results is comprehensively discussed. Attention is given to the importance of the acquisition frequency, intrinsic bias of having a short duration signal and influence of the investigating windows. For an adequate evaluation of the turbulent time scales, it is found that comparing experiments and numerics for high Reynolds number flows inferring small-scale phenomena requires to obey a set of rules, otherwise important errors can be made. If adequately processed, LES and HWA are found to agree well indicating the potential of LES for such problems.},
keywords = { Turbulence, Engines, Combustion chambers},
url = {http://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleid=2428454}}

Scholl, S., Verstraete, T., Torres-Garcia, J., Duchaine, F. and Gicquel, L. (2015) Influence of the thermal boundary conditions on the heat transfer of a rib-roughened cooling channel using LES, 11th european turbomachinery conference., Madrid, Espagne 2015

[bibtex]
[url]

@CONFERENCE{PR-CFD-15-23528,
author = {Scholl, S. and Verstraete, T. and Torres-Garcia, J. and Duchaine, F. and Gicquel, L. },
title = {Influence of the thermal boundary conditions on the heat transfer of a rib-roughened cooling channel using LES},
year = {2015},
address = {Madrid, Espagne},
booktitle = {11th european turbomachinery conference},
url = {http://www.cerfacs.fr/~cfdbib/repository/TR_CFD_15_27.pdf}}

Rochoux, M., Cuenot, B., Duchaine, F., Riber, E., Veynante, D. and Darabiha, N. (2015) Analysis of large-eddy simulations of laboratory-scale fire, 15th International Conference on Numerical Combustion., Avignon, France 2015

[bibtex]

@CONFERENCE{PR-CFD-15-26902,
author = {Rochoux, M. and Cuenot, B. and Duchaine, F. and Riber, E. and Veynante, D. and Darabiha, N. },
title = {Analysis of large-eddy simulations of laboratory-scale fire},
year = {2015},
address = {Avignon, France},
booktitle = {15th International Conference on Numerical Combustion}}

Duchaine, F., Papadogiannis, D., Gicquel, L., de Laborderie, J., Wang, G. and Moreau, S. (2015) Towards the simulation of compressor, combustion chamber and turbine interactions - Invited conference, 3rd ECCOMAS Young Investigators Conference., Aachen, Germany, 7 2015

[bibtex]

@CONFERENCE{PR-CFD-15-29513,
author = {Duchaine, F. and Papadogiannis, D. and Gicquel, L. and de Laborderie, J. and Wang, G. and Moreau, S. },
title = {Towards the simulation of compressor, combustion chamber and turbine interactions - Invited conference},
year = {2015},
month = {7},
booktitle = {3rd ECCOMAS Young Investigators Conference},
address = {Aachen, Germany}}

Duchaine, F. (2015) User presentation on Data Centric Approach in turbulent flows - Invited conference, European Exascale Software Initiative (EESI) Final Conference., Dublin Irlande 2015

[bibtex]
[url]

@CONFERENCE{PR-CFD-15-29515,
author = {Duchaine, F. },
title = {User presentation on Data Centric Approach in turbulent flows - Invited conference},
year = {2015},
address = {Dublin Irlande},
booktitle = {European Exascale Software Initiative (EESI) Final Conference},
url = {http://www.eesi-project.eu/wp-content/uploads/2015/05/Duchaine_-_CERFACS_-_Data_centric_approach_in_turbulent_flows_-_EESI2_Final_Conference.pdf }}

Duchaine, F. (2015) Efficient Couplers for Extreme Computing - Invited conference, 3rd ECCOMAS Young Investigators Conference., Dublin Irlande 2015

[bibtex]
[url]

@CONFERENCE{PR-CFD-15-29520,
author = {Duchaine, F. },
title = {Efficient Couplers for Extreme Computing - Invited conference},
year = {2015},
address = {Dublin Irlande},
booktitle = {3rd ECCOMAS Young Investigators Conference},
url = {http://www.eesi-project.eu/wp-content/uploads/2015/05/Duchaine_-_CERFACS_-_Efficient_couplers_-_EESI2_Final_Conference.pdf}}

Berger, S., Richard, S., Staffelbach, G., Duchaine, F. and Gicquel, L.Y.M. (2015) Aerothermal prediction of an aeronautical combustion chamber based on the coupling of Large Eddy Simulation, solid conduction and radiation solvers, ASME Turbo Expo 2015., Montreal, Canada, 6 2015

[bibtex]
[url]

@CONFERENCE{PR-CFD-15-34,
author = {Berger, S. and Richard, S. and Staffelbach, G. and Duchaine, F. and Gicquel, L.Y.M. },
title = {Aerothermal prediction of an aeronautical combustion chamber based on the coupling of Large Eddy Simulation, solid conduction and radiation solvers},
year = {2015},
month = {6},
booktitle = {ASME Turbo Expo 2015},
pages = {GT2015-42457},
address = {Montreal, Canada},
abstract = {A precise knowledge of the thermal environment is essential for gas turbines design. Combustion chamber walls in particular are subject to strong thermal constraints. It is thus essential for designers to characterize accurately the local thermal state of such devices. Today, the determination of wall temperatures is performed experimentally by complex thermocolor tests. To limit such expensive experiments and integrate the knowledge of the thermal environment earlier in the design process, efforts are currently performed to provide high fidelity numerical tools able to predict the combustion chamber walls temperature. Many coupled physical phenomena are involved: turbulent combustion, convection and mixing of hot products and cold flows, conduction in the solid parts as well as gas to gas, gas to wall and wall to wall radiative transfers. The resolution of such a multiphysics problem jointly in the fluid and the solid domains can be done numerically through the use of several dedicated numerical and algorithmic approaches. In this paper, a partitioned coupling methodology is used to investigate the solid steady state wall temperature of a helicopter combustor in take-off conditions. The methodology relies on a high fidelity Large Eddy Simulation reacting flow solver coupled to conduction and radiative solvers. Different computations are presented in order to assess the role of each heat transfer process in the temperature field. A conjugate heat transfer simulation is first proposed and compared with experimental thermocolor tests. The effect of radiation is then investigated comparing relative importance of convective and radiative heat fluxes.},
url = {http://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleid=2428270}}

Koupper, C., Bonneau, G., Caciolli, G., Facchini, B., Tarchi, L., Gicquel, L.Y.M. and Duchaine, F. (2014) Development of an engine representative combustor simulator dedicated to hot streak generation, Proceedings of asme turbo expo 2014: power for land, sea and air 2014., Dusseldorf, Germany 2014

[bibtex]

@conference{PR-CFD-14-23371,
author = {Koupper, C. and Bonneau, G. and Caciolli, G. and Facchini, B. and Tarchi, L. and Gicquel, L.Y.M. and Duchaine, F. },
title = {Development of an engine representative combustor simulator dedicated to hot streak generation},
year = {2014},
pages = {},
address = {Dusseldorf, Germany},
booktitle = {Proceedings of asme turbo expo 2014: power for land, sea and air 2014}}

Papadogiannis, D., Wang, G., Moreau, S., Duchaine, F., Sicot, F. and Gicquel, L.Y.M. (2014) Large Eddy Simulation of a high pressure turbine stage: effects of sub-grid scale modeling and mesh resolution, Proceedings of asme turbo expo 2014: power for land, sea and air 2014., Dusseldorf, Germany 2014

[bibtex]
[url]

@conference{PR-CFD-14-23453,
author = {Papadogiannis, D. and Wang, G. and Moreau, S. and Duchaine, F. and Sicot, F. and Gicquel, L.Y.M. },
title = {Large Eddy Simulation of a high pressure turbine stage: effects of sub-grid scale modeling and mesh resolution},
year = {2014},
pages = {},
address = {Dusseldorf, Germany},
booktitle = {Proceedings of asme turbo expo 2014: power for land, sea and air 2014},
url = {http://www.cerfacs.fr/~cfdbib/repository/TR_CFD_14_25.pdf}}

Shum Kivan, F., Duchaine, F. and Gicquel, L.Y.M. (2014) Large-eddy simulation and conjugate heat transfer in a round impinging jet, Proceedings of asme turbo expo 2014: turbine technical conference and exposition., Dusseldorf, Germany 2014

[bibtex]
[url]

@CONFERENCE{PR-CFD-14-23530,
author = {Shum Kivan, F. and Duchaine, F. and Gicquel, L.Y.M. },
title = {Large-eddy simulation and conjugate heat transfer in a round impinging jet},
year = {2014},
address = {Dusseldorf, Germany},
booktitle = {Proceedings of asme turbo expo 2014: turbine technical conference and exposition},
url = {http://www.cerfacs.fr/~cfdbib/repository/TR_CFD_14_24.pdf}}

Wang, G., Moreau, S., Duchaine, F. and Gicquel, L.Y.M. (2014) LES investigation of aerodynamics performance in an axial compressor stage, 22nd annual conference of the cfd society of canada., University of Toronto, Canada 2014

[bibtex]
[url]

@conference{PR-CFD-14-23575,
author = {Wang, G. and Moreau, S. and Duchaine, F. and Gicquel, L.Y.M. },
title = {LES investigation of aerodynamics performance in an axial compressor stage},
year = {2014},
address = {University of Toronto, Canada},
booktitle = {22nd annual conference of the cfd society of canada},
url = {http://www.cerfacs.fr/~cfdbib/repository/TR_CFD_14_34.pdf}}

Cuenot, B., Gicquel, L.Y.M., Riber, E., Staffelbach, G., Vermorel, O., Dauptain, A., Duchaine, F. and Poinsot, Th. (2013) Simulations aux Grandes Echelles: instabilités thermo-acoustiques, combustion diphasique et couplages multi-physiques - invited conference, 21 ième congrès français de mécanique - bordeaux, france. 2013

[bibtex]
[url]

@conference{PR-CFD-13-23224,
author = {Cuenot, B. and Gicquel, L.Y.M. and Riber, E. and Staffelbach, G. and Vermorel, O. and Dauptain, A. and Duchaine, F. and Poinsot, Th. },
title = {Simulations aux Grandes Echelles: instabilit´{e}s thermo-acoustiques, combustion diphasique et couplages multi-physiques - invited conference},
year = {2013},
booktitle = {21 i`{e}me congr`{e}s franc{c}ais de m´{e}canique - bordeaux, france},
url = {http://www.cerfacs.fr/~cfdbib/repository/TR_CFD_13_68.pdf}}

Duchaine, F., Maheau, N., Moureau, V., Balarac, G. and Moreau, S. (2013) Large Eddy Simulation and conjugate heat transfer around a low-mach turbine blade, Proceedings of asme turbo expo 2013., San Antonio, Texas, USA 2013

[bibtex]
[url]

@conference{PR-CFD-13-23267,
author = {Duchaine, F. and Maheau, N. and Moureau, V. and Balarac, G. and Moreau, S. },
title = {Large Eddy Simulation and conjugate heat transfer around a low-mach turbine blade},
year = {2013},
pages = {},
address = {San Antonio, Texas, USA},
booktitle = {Proceedings of asme turbo expo 2013},
url = {http://www.cerfacs.fr/~cfdbib/repository/TR_CFD_13_10.pdf}}

Wang, G., Papadogiannis, D., Duchaine, F., Gourdain, N. and Gicquel, L.Y.M. (2013) Towards massively parallel large eddy simulation of turbine stages, Asme turbo expo 2013 gas turbine technical congress & exposition., San Antonio, USA 2013

[bibtex]
[url]

@conference{PR-CFD-13-23574,
author = {Wang, G. and Papadogiannis, D. and Duchaine, F. and Gourdain, N. and Gicquel, L.Y.M. },
title = {Towards massively parallel large eddy simulation of turbine stages},
year = {2013},
address = {San Antonio, USA},
booktitle = {Asme turbo expo 2013 gas turbine technical congress & exposition},
url = {http://www.cerfacs.fr/~cfdbib/repository/TR_CFD_13_2.pdf}}

Habert, J., Ricci, S., Piacentini, A, Jonville, G., Morel, T., Duchaine, F., Thévenin, A., Le Pape, E., Thual, O., Goutal, N., Zaoui, F. and Ata, R. (2012) Estimation of lateral inflows using data assimilation in the context of real-time flood forecasting for the Marne catchment in France XIXth telemac-mascaret user conference, october 18-19, Oxford, UK 2012

[bibtex]

@CONFERENCE{PR-CMGC-12-22045,
author = {Habert, J. and Ricci, S. and Piacentini, A and Jonville, G. and Morel, T. and Duchaine, F. and Thévenin, A. and Le Pape, E. and Thual, O. and Goutal, N. and Zaoui, F. and Ata, R. },
title = {Estimation of lateral inflows using data assimilation in the context of real-time flood forecasting for the Marne catchment in France},
year = {2012},
organization = {XIXth telemac-mascaret user conference, october 18-19},
address = {Oxford, UK}}

Piacentini, A, Ricci, S., Le Pape, E., Habert, J., Jonville, G., Goutal, N., Barthélémy, S., Morel, T., Duchaine, F. and Thual, O. (2012) Towards operational flood forecasting using data assimilation AGU fall meeting, 3-7 december , San Francisco, USA 2012

[bibtex]

@CONFERENCE{PR-CMGC-12-22218,
author = {Piacentini, A and Ricci, S. and Le Pape, E. and Habert, J. and Jonville, G. and Goutal, N. and Barthélémy, S. and Morel, T. and Duchaine, F. and Thual, O. },
title = {Towards operational flood forecasting using data assimilation},
year = {2012},
organization = {AGU fall meeting, 3-7 december },
address = {San Francisco, USA}}

Ricci, S., Piacentini, A, Le Pape, E., Habert, J., Jonville, G., Goutal, N., Barthélémy, S., Morel, T., Duchaine, F. and Thual, O. (2012) Towards operational flood forecasting using data assimilation AGU fall meeting american geophysical union, 5-9 december, San Francisco, USA 2012

[bibtex]

@CONFERENCE{PR-CMGC-12-22254,
author = {Ricci, S. and Piacentini, A and Le Pape, E. and Habert, J. and Jonville, G. and Goutal, N. and Barthélémy, S. and Morel, T. and Duchaine, F. and Thual, O. },
title = {Towards operational flood forecasting using data assimilation},
year = {2012},
organization = {AGU fall meeting american geophysical union, 5-9 december},
address = {San Francisco, USA}}

Ricci, S., Piacentini, A, Riadh, A., Goutal, N., Razafindrakoto, E., Zaoui, F., Gant, M., Morel, T., Duchaine, F. and Thual, O. (2012) A variational data assimilation algorithm to better estimate the salinity for the Berre lagoon with TELEMAC AGU fall meeting, american geophysical union, 5-9 december 2012

[bibtex]

@CONFERENCE{PR-CMGC-12-22256,
author = {Ricci, S. and Piacentini, A and Riadh, A. and Goutal, N. and Razafindrakoto, E. and Zaoui, F. and Gant, M. and Morel, T. and Duchaine, F. and Thual, O. },
title = {A variational data assimilation algorithm to better estimate the salinity for the Berre lagoon with TELEMAC},
year = {2012},
organization = {AGU fall meeting, american geophysical union, 5-9 december}}

Moureau, V., Duchaine, F. and Balarac, G. (2012) Large-eddy simulations of flow and heat transfer around a low-mach number turbine blade, In Proceedings of the Summer Program Center for Turbulence Research. NASA AMES - Stanford University, Stanford, USA 2012

[bibtex]

@CONFERENCE{PR-CMGC-12-22732,
author = {Moureau, V. and Duchaine, F. and Balarac, G. },
title = {Large-eddy simulations of flow and heat transfer around a low-mach number turbine blade},
year = {2012},
booktitle = {In Proceedings of the Summer Program Center for Turbulence Research},
organization = {NASA AMES - Stanford University},
address = {Stanford, USA}}

Gicquel, L.Y.M., Cuenot, B., Staffelbach, G., Vermorel, O., Riber, E., Dauptain, A., Duchaine, F., Gourdain, N., Sicot, F. and Poinsot, Th. (2012) CERFACS state-of-the-art and recent investigations for temperature predictions in turbo-machineries - invited conference, Conference on high fidelity simulations of combustion turbine systems., GE RC Niskayuna, NY, USA 2012

[bibtex]
[url]

@conference{PR-CFD-12-23326,
author = {Gicquel, L.Y.M. and Cuenot, B. and Staffelbach, G. and Vermorel, O. and Riber, E. and Dauptain, A. and Duchaine, F. and Gourdain, N. and Sicot, F. and Poinsot, Th. },
title = {CERFACS state-of-the-art and recent investigations for temperature predictions in turbo-machineries - invited conference},
year = {2012},
address = {GE RC Niskayuna, NY, USA},
booktitle = {Conference on high fidelity simulations of combustion turbine systems},
url = {http://www.cerfacs.fr/~cfdbib/repository/TR_CFD_12_44.pdf}}

Mari, R., Cuenot, B., Duchaine, F. and Selle, L. (2012) Stabilization mechanisms of a supercritical hydrogen/oxygen flame, Proceedings of the 2012 summer program., Center for Turbulence Research, NASA AMES, Stanford University, USA 2012

[bibtex]
[url]

@conference{PR-CFD-12-23409,
author = {Mari, R. and Cuenot, B. and Duchaine, F. and Selle, L. },
title = {Stabilization mechanisms of a supercritical hydrogen/oxygen flame},
year = {2012},
pages = {439 - 448},
address = {Center for Turbulence Research, NASA AMES, Stanford University, USA},
booktitle = {Proceedings of the 2012 summer program},
url = {http://www.cerfacs.fr/~cfdbib/repository/TR_CFD_12_83.pdf}}

Jauré, S., Duchaine, F. and Gicquel, L.Y.M. (2011) Comparisons of coupling strategies for massively parallel conjugate
heat transfer with large eddy simulation, In iv international conference on computational methods for coupled problems in science and engineering., Kos Island, Greece 2011

[bibtex]

@conference{PR-CMGC-11-22060,
author = {Jaur´{e}, S. and Duchaine, F. and Gicquel, L.Y.M. },
title = {Comparisons of coupling strategies for massively parallel conjugate
heat transfer with large eddy simulation},
year = {2011},
address = {Kos Island, Greece},
booktitle = {In iv international conference on computational methods for coupled
problems in science and engineering}}

Piacentini, A., Morel, T., Thévenin, A. and Duchaine, F. (2011) Open-palm: an open source dynamic parallel coupler., In iv international conference on computational methods for coupled problems in science and engineering. 2011

[bibtex]

@conference{PR-CMGC-11-22217,
author = {Piacentini, A. and Morel, T. and Th´{e}venin, A. and Duchaine, F. },
title = {Open-palm: an open source dynamic parallel coupler.},
year = {2011},
booktitle = {In iv international conference on computational methods for coupled
problems in science and engineering}}

Dauptain, A., Frichet, G., Duchaine, F., Riber, E., Dejean, G. and Poinsot, T. (2011) Transferring Large Eddy Simulation tools from laboratories experts to industry users: a challenge for the INCA community, 3ème colloque INCA., ONERA Toulouse, France 2011

[bibtex]
[url]

@CONFERENCE{PR-CFD-11-23240,
author = {Dauptain, A. and Frichet, G. and Duchaine, F. and Riber, E. and Dejean, G. and Poinsot, T. },
title = {Transferring Large Eddy Simulation tools from laboratories experts to industry users: a challenge for the INCA community},
year = {2011},
booktitle = {3ème colloque INCA},
address = {ONERA Toulouse, France},
url = {http://www.cerfacs.fr/~cfdbib/repository/TR_CFD_11_112.pdf}}

Fransen, R., Collado, E., Duchaine, F., Gourdain, N., Gicquel, L.Y.M., Vial, L. and Bonneau, G. (2011) Comparison of RANS and LES in high pressure turbines, 3ème colloque inca., ONERA Toulouse 2011

[bibtex]
[url]

@conference{PR-CFD-11-23294,
author = {Fransen, R. and Collado, E. and Duchaine, F. and Gourdain, N. and Gicquel, L.Y.M. and Vial, L. and Bonneau, G. },
title = {Comparison of RANS and LES in high pressure turbines},
year = {2011},
address = {ONERA Toulouse},
booktitle = {3`{e}me colloque inca},
url = {http://www.cerfacs.fr/~cfdbib/repository/TR_CFD_11_144.pdf}}

Gicquel, L.Y.M., Cuenot, B., Staffelbach, G., Vermorel, O., Riber, E., Dauptain, A., Duchaine, F. and Poinsot, Th. (2011) LES modeling and sensitivity issues - implications on the prediction and flame dynamics - invited conference, Ge global research symposium on LES of turbulent reacting flows for GT design., Niskayuna, NY, USA 2011

[bibtex]

@conference{PR-CFD-11-23325,
author = {Gicquel, L.Y.M. and Cuenot, B. and Staffelbach, G. and Vermorel, O. and Riber, E. and Dauptain, A. and Duchaine, F. and Poinsot, Th. },
title = {LES modeling and sensitivity issues - implications on the prediction and flame dynamics - invited conference},
year = {2011},
address = {Niskayuna, NY, USA},
booktitle = {Ge global research symposium on LES of turbulent reacting flows for GT design}}

Jauré, S., Duchaine, F. and Gicquel, L.Y.M. (2011) Comparisons of coupling strategies for massively parallel conjugate heat transfer with large eddy simulation, Iv international conference on computational methods for coupled problems in science and engineering - coupled problems 2011., KOS ISLAND, GREECE 2011

[bibtex]
[url]

@conference{PR-CFD-11-23360,
author = {Jaur´{e}, S. and Duchaine, F. and Gicquel, L.Y.M. },
title = {Comparisons of coupling strategies for massively parallel conjugate heat transfer with large eddy simulation},
year = {2011},
pages = {},
address = {KOS ISLAND, GREECE},
booktitle = {Iv international conference on computational methods for coupled problems in science and engineering - coupled problems 2011},
url = {http://www.cerfacs.fr/~cfdbib/repository/TR_CFD_11_143.pdf}}

Gourdain, N., Duchaine, F., Gicquel, L.Y.M. and Collado, E. (2010) Advanced numerical simulation dedicated to the prediction of heat transfer in a highly loaded turbine guide vane, Asme turbo expo, paper gt2010-22793., Glasgow, United Kingdom 2010

[bibtex]

@conference{PR-CFD-10-20997,
author = {Gourdain, N. and Duchaine, F. and Gicquel, L.Y.M. and Collado, E. },
title = {Advanced numerical simulation dedicated to the prediction of heat transfer in a highly loaded turbine guide vane},
year = {2010},
address = {Glasgow, United Kingdom},
booktitle = {Asme turbo expo, paper gt2010-22793}}

Léonard, T., Duchaine, F., Gourdain, N. and Gicquel, L.Y.M. (2010) Steady/unsteady reynolds averaged navier-stokes and Large Eddy Simulations of a turbine blade at high subsonic outlet mach number, Proceedings of the asme turbo expo 2010 gas turbine technical congress & exposit., Glasgow, UK 2010

[bibtex]

@conference{PR-CFD-10-23378,
author = {L´{e}onard, T. and Duchaine, F. and Gourdain, N. and Gicquel, L.Y.M. },
title = {Steady/unsteady reynolds averaged navier-stokes and Large Eddy Simulations of a turbine blade at high subsonic outlet mach number},
year = {2010},
pages = {},
address = {Glasgow, UK},
booktitle = {Proceedings of the asme turbo expo 2010 gas turbine technical congress & exposit}}

Wlassow, F., Duchaine, F., Leroy, G. and Gourdain, N. (2010) 3D simulation of coupled fluid flow and solid heat conduction for the calculation of blade wall temperature in a turbine stage, Asme turbo expo., Glasgow, UK 2010

[bibtex]

@conference{PR-CFD-10-23584,
author = {Wlassow, F. and Duchaine, F. and Leroy, G. and Gourdain, N. },
title = {3D simulation of coupled fluid flow and solid heat conduction for the calculation of blade wall temperature in a turbine stage},
year = {2010},
pages = {},
address = {Glasgow, UK},
booktitle = {Asme turbo expo}}

Dufour, G., Gourdain, N., Duchaine, F., Vermorel, O., Gicquel, L.Y.M. and Boussuge, J.-F. (2009) Large Eddy Simulation applications - invited conference, Vki lecture series on : numerical investigations in turbomachinery: the state-of-the-art., Van Karman Institute, Brussels, Belgium 2009

[bibtex]
[url]

@conference{PR-CFD-09-23274,
author = {Dufour, G. and Gourdain, N. and Duchaine, F. and Vermorel, O. and Gicquel, L.Y.M. and Boussuge, J.-F. },
title = {Large Eddy Simulation applications - invited conference},
year = {2009},
address = {Van Karman Institute, Brussels, Belgium},
booktitle = {Vki lecture series on : numerical investigations in turbomachinery: the state-of-the-art},
url = {http://www.cerfacs.fr/~cfdbib/repository/TR_CFD_09_156.pdf}}

Duchaine, F., Mendez, S., Nicoud, F., Corpron, A., Moureau, V. and Poinsot, Th. (2008) Coupling heat transfer solvers and Large Eddy Simulations for combustion applications, Proceedings of the summer program., Center for Turbulence Research, NASA AMES, Stanford University, USA 2008

[bibtex]
[url]

@conference{PR-CFD-08-20834,
author = {Duchaine, F. and Mendez, S. and Nicoud, F. and Corpron, A. and Moureau, V. and Poinsot, Th. },
title = {Coupling heat transfer solvers and Large Eddy Simulations for combustion applications},
year = {2008},
pages = {113 - 126},
address = {Center for Turbulence Research, NASA AMES, Stanford University, USA},
booktitle = {Proceedings of the summer program},
url = {http://www.cerfacs.fr/~cfdbib/repository/TR_CFD_08_99.pdf}}

Duchaine, F., Mendez, S., Nicoud, F., Corpron, A., Moureau, V. and Poinsot, Th. (2008) Conjugate heat transfer with Large Eddy Simulation. application to gas turbine components, 2ème colloque inca., CORIA, Rouen, France 2008

[bibtex]

@conference{PR-CFD-08-23261,
author = {Duchaine, F. and Mendez, S. and Nicoud, F. and Corpron, A. and Moureau, V. and Poinsot, Th. },
title = {Conjugate heat transfer with Large Eddy Simulation. application to gas turbine components},
year = {2008},
address = {CORIA, Rouen, France},
booktitle = {2`{e}me colloque inca}}

Duchaine, F., Gicquel, L.Y.M., Poinsot, Th., Bissières, D. and Bérat, C. (2006) Optimization loop based on a CFD RANS code, Icas 2006., Munich, Germany 2006

[bibtex]
[url]

@conference{PR-CFD-06-23260,
author = {Duchaine, F. and Gicquel, L.Y.M. and Poinsot, Th. and Bissi`{e}res, D. and B´{e}rat, C. },
title = {Optimization loop based on a CFD RANS code},
year = {2006},
address = {Munich, Germany},
booktitle = {Icas 2006},
url = {http://www.cerfacs.fr/~cfdbib/repository/TR_CFD_06_20.pdf}}

Duchaine, F., Gicquel, L.Y.M., Bissières, D., Bérat, C. and Poinsot, Th. (2005) Automatic design optimization applied to lean premixed combustor cooling, 1st workshop inca., SNECMA Villaroche, France 2005

[bibtex]
[url]

@conference{PR-CFD-05-23257,
author = {Duchaine, F. and Gicquel, L.Y.M. and Bissi`{e}res, D. and B´{e}rat, C. and Poinsot, Th. },
title = {Automatic design optimization applied to lean premixed combustor cooling},
year = {2005},
pages = {295 - 304},
address = {SNECMA Villaroche, France},
booktitle = {1st workshop inca},
url = {http://www.cerfacs.fr/~cfdbib/repository/TR_CFD_05_94.pdf}}

Gicquel, L.Y.M., Vermorel, O., Duchaine, F., Riber, E., Dauptain, A., Staffelbach, G., Cuenot, B. and Poinsot, T. (2013) Best Practice Guidelines in Computational Fluid Dynamics of Turbulent combustion, ERCOFTAC

[bibtex]

@BOOK{BK-CFD-13-3,
author = {Gicquel, L.Y.M. and Vermorel, O. and Duchaine, F. and Riber, E. and Dauptain, A. and Staffelbach, G. and Cuenot, B. and Poinsot, T. },
title = {Best Practice Guidelines in Computational Fluid Dynamics of Turbulent combustion},
year = {2013},
month = {2},
chaptertitle = {Gas Turbine and Industrial Burners},
publisher = {ERCOFTAC},
chapter = {4}}

Morel, T., Duchaine, F. and Fares, MBarek (2016) Rapport d'activités 2015 sur la collaboration Cerfacs/ONERA autour du coupleur OpenPALM et de la composante CWIPI, UMR 5318 CECI, CERFACS-CNRS, TR-CMGC-16-36, Technical report

[bibtex]

@TECHREPORT{TR-CMGC-16-36,
author = {Morel, T. and Duchaine, F. and Fares, MBarek },
title = {Rapport d'activités 2015 sur la collaboration Cerfacs/ONERA autour du coupleur OpenPALM et de la composante CWIPI},
year = {2016},
institution = {UMR 5318 CECI, CERFACS-CNRS, TR-CMGC-16-36},
address = {Toulouse, France},
type = {Technical report},
abstract = {Ce document présente les différents éléments de la collaboration Cerfacs-ONERA 2015 autour du coupleur dynamique de codes parallèles OpenPALM. L'année a été marquée par la fin du projet FUI COSMOS+, la prise en main par le Cerfacs de développements dans CWIPI, des tests de performance en comparaison avec le coupleur OASIS développé par le Cerfacs, de tests de CWIPI sur des calculateurs haute performance et enfin du montage d'un nouveau projet financé qui pourrait aboutir courant 2016. }}

Morel, T. and Duchaine, F. (2016) PALM_PARASOL version 2.0, manuel utilisateur, UMR 5318 CECI, CERFACS-CNRS, TR-CMGC-16-307, Technical report

[bibtex] [pdf]

@TECHREPORT{TR-CMGC-16-307,
author = {Morel, T. and Duchaine, F. },
title = {PALM_PARASOL version 2.0, manuel utilisateur},
year = {2016},
institution = {UMR 5318 CECI, CERFACS-CNRS, TR-CMGC-16-307},
address = {Toulouse, France},
type = {Technical report},
pdf = {https://cerfacs.fr/wp-content/uploads/2016/12/GLOBC-TR-PALM-User-manuel-2016.pdf}}

Duchaine, F., Staffelbach, G., Gicquel, L.Y.M. and de Laborderie, J. (2015) GENCI/CINES : rapport de grand challenge sur OCCIGEN - simulations aux grandes échelles d un compresseur axial multi-étages, Cerfacs, technical report

[bibtex]

@TECHREPORT{TR-CFD-15-20843,
author = {Duchaine, F. and Staffelbach, G. and Gicquel, L.Y.M. and de Laborderie, J. },
title = {GENCI/CINES : rapport de grand challenge sur OCCIGEN - simulations aux grandes échelles d un compresseur axial multi-étages},
year = {2015},
institution = {Cerfacs},
month = {3},
type = {technical report}}

Duchaine, F. (2013) Rapport de cadrage: développement et industrialisation d'une chaîne de calcul de thermique de parois de chambre de combustion, Cerfacs, technical report

[bibtex]

@TECHREPORT{TR-CFD-13-20839,
author = {Duchaine, F. },
title = {Rapport de cadrage: développement et industrialisation d'une chaîne de calcul de thermique de parois de chambre de combustion},
year = {2013},
institution = {Cerfacs},
type = {technical report}}

Morel, T., Duchaine, F., Thévenin, A., Piacentini, A, Kirmse, M. and Quémerais, E. (2013) Coupleur OpenPALM version 4.1.7 user guide and training manual, URA SUC 1875, CERFACS-CNRS, TR-CMGC-13-22814, Technical report

[bibtex]

@TECHREPORT{TR-CMGC-13-22814,
author = {Morel, T. and Duchaine, F. and Thévenin, A. and Piacentini, A and Kirmse, M. and Quémerais, E. },
title = {Coupleur OpenPALM version 4.1.7 user guide and training manual},
year = {2013},
institution = {URA SUC 1875, CERFACS-CNRS, TR-CMGC-13-22814},
address = {Toulouse, France},
type = {Technical report}}

Trespeuch, P., Valcke, S., Morel, T. and Duchaine, F. (2012) Réalisation d'un modèle couplé océan-atmosphère avec le coupleur dynamique de codes parallèles OpenPALM, URA SUC 1875, CERFACS-CNRS, TR-CMGC-12-22758, Technical report

[bibtex] [pdf]

@TECHREPORT{TR-CMGC-12-22758,
author = {Trespeuch, P. and Valcke, S. and Morel, T. and Duchaine, F. },
title = {Réalisation d'un modèle couplé océan-atmosphère avec le coupleur dynamique de codes parallèles OpenPALM},
year = {2012},
institution = {URA SUC 1875, CERFACS-CNRS, TR-CMGC-12-22758},
address = {Toulouse, France},
type = {Technical report},
pdf = {https://cerfacs.fr/wp-content/uploads/2018/09/GLOBC_RT_Trespeuch_Rapport_2012.pdf}}

Duchaine, F. and Boileau, M. (2009) Calcul aérothermique par SGE de l'expérimentation E - Validation du chaînage AVBP /TMP, Cerfacs, rapport contractuel

[bibtex]

@techreport{TR-CFD-09-23262,
author = {Duchaine, F. and Boileau, M. },
title = {Calcul a´{e}rothermique par SGE de l´exp´{e}rimentation E - Validation du cha^{i}nage AVBP /TMP},
year = {2009},
institution = {Cerfacs},
month = {5},
type = {rapport contractuel}}

Duchaine, F. and Boileau, M. (2009) Comparaison des méthodes U-RANS et SGE dans le cas d'une configuration aérothermique proche des écoulements présents dans les zones d'intégration des moteurs, Cerfacs, rapport contractuel

[bibtex]

@techreport{TR-CFD-09-23263,
author = {Duchaine, F. and Boileau, M. },
title = {Comparaison des m´{e}thodes U-RANS et SGE dans le cas d´une configuration a´{e}rothermique proche des ´{e}coulements pr´{e}sents dans les zones d´int´{e}gration des moteurs},
year = {2009},
institution = {Cerfacs},
month = {5},
type = {rapport contractuel}}

Boileau, M. and Duchaine, F. (2008) Calculs aérothermiques AVBP/TMG appliqués à
l'intégration thermique en zones nacelle - livrable 1 : étude bibliographique, Cerfacs, rapport contractuel

[bibtex]

@techreport{TR-CFD-08-23177,
author = {Boileau, M. and Duchaine, F. },
title = {Calculs a´{e}rothermiques AVBP/TMG appliqu´{e}s `{a}
l´int´{e}gration thermique en zones nacelle - livrable 1 : ´{e}tude bibliographique},
year = {2008},
institution = {Cerfacs},
month = {9},
type = {rapport contractuel}}

Duchaine, F. (2006) Guide d'utilisation de la chaîne de calcul thermique N3SNatur-ASTRE-Abaqus pour la prédiction des températures de parois, Cerfacs

[bibtex]

@techreport{TR-CFD-06-20831,
author = {Duchaine, F. },
title = {Guide d´utilisation de la cha^{i}ne de calcul thermique N3SNatur-ASTRE-Abaqus pour la pr´{e}diction des temp´{e}ratures de parois},
year = {2006},
institution = {Cerfacs},
month = {7}}

Duchaine, F. (2005) Palmérisation de N3SNatur, Cerfacs

[bibtex]
[url]

@techreport{TR-CFD-05-23258,
author = {Duchaine, F. },
title = {Palm´{e}risation de N3SNatur},
year = {2005},
institution = {Cerfacs},
month = {2},
url = {http://www.cerfacs.fr/~cfdbib/repository/TR_CFD_05_8.pdf}}

Duchaine, F. (2004) Optimisation de turbomoteur d'hélicoptère - Stage en collaboration avec TURBOMECA, Cerfacs, rapport de stage de mastère mécanique des fluides numérique

[bibtex]
[url]

@techreport{TR-CFD-04-23256,
author = {Duchaine, F. },
title = {Optimisation de turbomoteur d´h´{e}licopt`{e}re - Stage en collaboration avec TURBOMECA},
year = {2004},
institution = {Cerfacs},
month = {8},
type = {rapport de stage de mast`{e}re m´{e}canique des fluides num´{e}rique},
url = {http://www.cerfacs.fr/~cfdbib/repository/WN_CFD_04_76.pdf}}