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@ARTICLE{AR-CFD-22-1, author = {Veilleux, A. and Puigt, G. and Deniau, H. and Daviller, G. }, title = {A stable Spectral Difference approach for computations with triangular and hybrid grids up to the 6th order of accuracy}, year = {2022}, volume = {449}, pages = {110774}, doi = {10.1016/j.jcp.2021.110774}, journal = {Journal of Computational Physics}, abstract = {In the present paper, a stable Spectral Difference formulation on triangles is defined using a flux polynomial expressed in the Raviart-Thomas basis up to the sixth-order of accuracy. Compared to the literature on the Spectral Difference approach, the present work increases the order of accuracy that the stable formulation can deal with. The proposed scheme is based on a set of flux points defined in the paper. The sets of points leading to a stable formulation are determined using a Fourier stability analysis of the linear advection equation coupled with an optimization process. The proposed Spectral Difference formulation differs from the Flux Reconstruction method on hybrid grids: the distinction between the two approaches is highlighted through the definition of the number of interior flux points. Validation starts from a convergence study using Euler equations and continues with simulations of laminar viscous flows over the NACA0012 airfoil using quadratic triangles and around a cylinder using a hybrid grid.}, url = {https://www.sciencedirect.com/science/article/pii/S0021999121006690#!}}

@ARTICLE{AR-CFD-22-2, author = {Di Renzo, M. }, title = {HTR-1.3 solver: Predicting electrified combustion using the hypersonic task-based research solver}, year = {2022}, volume = {272}, pages = {108247}, doi = {10.1016/j.cpc.2021.108247}, journal = {Computer Physics Communications}, abstract = {This manuscript presents an updated open-source version of the Hypersonics Task-based Research (HTR) solver. The solver, whose main features are presented in Di Renzo et al. (2020) [9] and Di Renzo & Pirozzoli (2021) [10], is designed for direct numerical simulation of reacting flows at high Reynolds numbers. This new version extends the applications of the HTR solver to turbulent combustion in the presence of external electric fields. In particular, a new distributed Poisson solver compatible with heterogeneous architectures has been incorporated in the algorithm to compute the electric potential distribution in bi-periodic configurations. The drift fluxes of the electrically charged species are now included in the transport equations using a targeted essentially non-oscillatory scheme. A verification of these new features of the solver is provided using one-dimensional burner stabilized flames, whereas a three dimensional turbulent flame is utilized to discuss the scalability of the proposed numerical tool.}, keywords = {Compressible reacting flows, GPUs, High-order numerics, Chemi-ionization}, url = {https://www.sciencedirect.com/science/article/pii/S0010465521003593?via%3Dihub}}

@ARTICLE{AR-CFD-22-5, author = {Blanchard, S. and Cazères, Q. and Cuenot, B. }, title = {Chemical modeling for methane oxy-combustion in Liquid Rocket Engines}, year = {2022}, volume = {190}, pages = {98-111}, doi = {10.1016/j.actaastro.2021.09.039}, journal = {Acta Astronautica}, abstract = {Methane–oxygen burning is considered for many future rocket engines for practicality and cost reasons. As this combustion is slower than hydrogen–oxygen, flame ignition and stability may be more difficult to obtain. To address these questions, numerical simulation with realistic chemistry is appropriate. However the high pressure and turbulence intensity encountered in rocket engines enhance drastically the stiffness of methane oxy-combustion. In this work, Analytically Reduced Chemistry (ARC) is proposed for accurate chemistry description at a reasonable computational cost. An ARC scheme is specifically derived for typical rocket engine conditions. It is validated by comparison with its parent skeletal mechanism on a series of laminar flames. Then the numerical stiffness of chemistry is overcome with an original approach for time integration, allowing to run simulations close to the acoustic time step whatever the chemical stiffness. It is demonstrated on laminar cases that the flame structure is well preserved, and that numerical stability is ensured while decreasing significantly the computational cost. The performance of ARC with the fast time integration method is finally demonstrated in a 3D Large-Eddy Simulation of a lab-scale Liquid Rocket Engine combustion chamber, where a detailed flame analysis is conducted.}, keywords = {LES, Methane oxy-combustion, Chemical kinetics, Implicitation, Liquid Rocket Engine}, url = {https://www.sciencedirect.com/science/article/pii/S0094576521005245?via%3Dihub}}

@ARTICLE{AR-CFD-22-7, author = {Fiore, M. and Daroukh, M. and Montagnac, M. }, title = {Loss assessment of the NASA SDT configuration using LES with phase-lagged assumption}, year = {2022}, volume = {234}, pages = {105256}, doi = {10.1016/j.compfluid.2021.105256}, journal = {Computers and Fluids}, abstract = {This paper presents the numerical study of the Source Diagnostic Test fan rig of the NASA Glenn (NASA SDT). Large-Eddy Simulations (LES) based on a finite volume approach are performed for the three different Outlet Guide Vane (OGV) geometries (baseline, low-count and low-noise) and three rotational speeds corresponding to approach, cutback and sideline operating conditions respectively. The full stage and nacelle geometries are considered in the numerical simulations, and results are compared to available measurements. The NASA SDT configuration is equipped respectively with 22 fan blades and either 26 of 54 vanes depending on the OGV geometry. The simulation domain could only be reduced to half of the full annulus and would still be a significant cost for the LES. In order to reduce computational cost, an LES with phase-lagged assumption approach is used. This method allows to perform unsteady simulations of multistage turbomachinery configurations including multiple frequency flows with a reduced computational domain composed of one single blade passage for each row. The large data storage required by the phase-lagged approach is handled by a compression method based on a Proper Orthogonal Decomposition replacing the traditional Fourier series decomposition. This compression method improves the signal spectral content especially at high frequency. Based on the numerical simulations, the flow field is described and used to assess the losses generated in the turbofan configuration based on an entropy approach. The results show different flow topologies for the fan depending on the rotational speed with a leading edge shock at high rotational speed. The fan boundary layer contributes strongly to losses with the majority of the losses being generated close to the leading edge for the dissipation due to mean strains and close to the recirculation zone occurring on the suction side for the turbulent kinetic energy production.}, url = {https://www.sciencedirect.com/science/article/abs/pii/S0045793021003571}}

@ARTICLE{AR-PA-21-208, author = {Agullo, E. and Altenbernd, M. and Anzt, H. and Bautista-Gomez, L.A. and Benacchio, T. and Bonaventura, L. and Bungartz, H.J. and Chatterjee, S. and Ciorba, F.M. and DeBardeleben, N. and Drzisga, D. and Eibl, S. and Engelmann, C. and Gansterer, W.N. and Giraud, L. and Göddeke, D. and Heisig, M. and Jézéquel, F. and Kohl, N. and Li, X.S. and Lion, R. and Mehl, M. and Mycek, P. and Obersteiner, M. and Quintana-Orti, E.S. and Rizzi, F. and Ruede, U. and Schulz, M. and Fung, F. and Speck, R. and Stals, L. and Teranishi, K. and Thibault, S. and Thönnes, D. and Wagner, A. and Wohlmuth, B. }, title = {Resiliency in numerical algorithm design for extreme scale simulations}, year = {2021}, pages = {10943420211055188}, doi = {10.1177/10943420211055188}, journal = {International Journal of High Performance Computing Applications}, url = {https://journals.sagepub.com/doi/10.1177/10943420211055188}}