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@ARTICLE{AR-CFD-19-156, 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 = {2019}, volume = {online}, 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}}

@ARTICLE{AR-CMGC-19-139, author = {Fisher, R.A. and Wieder, W.R. and Sanderson, B.M. and Koven, C.D. and Oleson, K.W. and Xu, C. and Fisher, J.B. and Shi, M. and Walker, A.P. and Lawrence, D.M. }, title = {Parametric controls on vegetation responses to biogeochemical forcing in the CLM5}, year = {2019}, volume = {11}, pages = {2879–2895}, doi = {10.1029/2019MS001609}, journal = {Journal of Advances in Modeling Earth Systems}, pdf = {https://cerfacs.fr/wp-content/uploads/2019/10/GLOBC-Fisher_et_al-102019-JAMES.pdf}}

@ARTICLE{AR-CMGC-19-135, author = {Massoud, E.C. and Xu, C. and Fisher, R.A. and Knox, R.G. and Walker, A.P. and Serbin, S.P. and Christoffersen, B.O. and Holm, J.A. and Kueppers, L.M. and Ricciuto, D.M. and Wei, L. and Johnson, D.J. and Chambers, J.Q. and Koven, C.D. and McDowell, N.G. and Vrugt, J.A. }, title = {Identification of key parameters controlling demographically structured vegetation dynamics in a land surface model: CLM4.5(FATES)}, year = {2019}, number = {9}, volume = {12}, pages = {4133–4164}, doi = {10.5194/gmd-12-4133-2019}, journal = {Geoscientific Model Development}, pdf = {https://cerfacs.fr/wp-content/uploads/2019/09/Globc-Article-Fisher-GeoSci.Mod_.pdf}, url = {https://www.geosci-model-dev.net/12/4133/2019/}}

@ARTICLE{AR-CMGC-19-119, author = {Emili, E. and Barret, B. and Le Flochmoën, E. and Cariolle, D. }, title = {Comparison between the assimilation of IASI Level 2 ozone retrievals and Level 1 radiances in a chemical transport model}, year = {2019}, number = {7}, volume = {12}, pages = {3963-3984}, doi = {doi.org/10.5194/amt-12-3963-2019}, journal = {Atmospheric Measurement Techniques}, pdf = {https://cerfacs.fr/wp-content/uploads/2019/08/GLOBC-Article-EMILI-amt-12-3963-2019.pdf}}

@ARTICLE{AR-CFD-19-120, author = {Muscat, L. and Puigt, G. and Montagnac, M. and Brenner, P. }, title = {A coupled implicit-explicit time integration method for compressible unsteady flows}, year = {2019}, number = {Article 108883}, volume = {398}, doi = {10.1016/j.jcp.2019.108883}, journal = {Journal of Computational Physics}, abstract = {This paper addresses how two time integration schemes, the Heun's scheme for explicit time integration and the second-order Crank-Nicolson scheme for implicit time integration, can be coupled spatially. This coupling is the prerequisite to perform a coupled Large Eddy Simulation / Reynolds Averaged Navier-Stokes computation in an industrial context, using the implicit time procedure for the boundary layer (RANS) and the explicit time integration procedure in the LES region. The coupling procedure is designed in order to switch from explicit to implicit time integrations as fast as possible, while maintaining stability. After introducing the different schemes, the paper presents the initial coupling procedure adapted from a published reference and shows that it can amplify some numerical waves. An alternative procedure, studied in a coupled time/space framework, is shown to be stable and with spectral properties in agreement with the requirements of industrial applications. The coupling technique is validated with standard test cases, ranging from one-dimensional to three-dimensional flows.}, keywords = {Hybrid time integration, Space-time stability analysis, Finite volume formulation, Compressible unsteady flows}, url = {https://doi.org/10.1016/j.jcp.2019.108883}}