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@ARTICLE{AR-PA-21-23, author = {Bauer, M. and Kostler, H. and Ruede, U. }, title = {lbmpy: Automatic code generation for efficient parallel lattice Boltzmann methods}, year = {2021}, volume = {49}, pages = {101269}, doi = {10.1016/j.jocs.2020.101269}, journal = {Journal of Computational Science}, pdf = {https://doi.org/10.1016/j.jocs.2020.101269}}

@ARTICLE{AR-CFD-21-53, author = {Renard, F. and Feng, Y. and Boussuge, J.-F. and Sagaut, P. }, title = {Improved compressible hybrid lattice Boltzmann method on standard lattice for subsonic and supersonic flows}, year = {2021}, number = {April 2021}, volume = {219}, pages = {104867 }, issn = {0045-7930}, doi = {10.1016/j.compfluid.2021.104867}, abstract = {A D2Q9 Hybrid Lattice Boltzmann Method (HLBM) is proposed for the simulation of both compressible subsonic and supersonic flows. This HLBM is an extension of the model of Feng et al. [1], which has been found, via different test cases, to be unstable for supersonic regimes. To circumvent this limitation, we propose:: (1) a new discretization of the lattice closure correction term that makes possible the simulation of supersonic flows, (2) a corrected viscous stress tensor that takes into account polyatomic gases, and (3) a novel discretization of the viscous heat production term fitting with the regularized formalism. The result is a hybrid method that resolves the mass and momentum equations with an LBM algorithm, and resolves the entropy-based energy equation with a finite volume method. This approach fully recovers the physics of the Navier–Stokes–Fourier equations with the ideal gas equation of state, and is valid from subsonic to supersonic regimes. It is then successfully assessed with both smooth flows and flows involving shocks. The proposed model is shown to be an efficient, accurate, and robust alternative to classic Navier–Stokes methods for the simulation of compressible flows}, keywords = {LBM, Compressible High speed flow, Shock waves, Aerodynamic noise}, url = {https://www.sciencedirect.com/science/article/abs/pii/S0045793021000335?via%3Dihub}}

@ARTICLE{AR-PA-21-45, author = {Mohanamuraly, P. and Müller, J.D. }, title = {An Adjoint‐assisted Multilevel Multifidelity Method for Uncertainty Quantification And Its Application To Turbomachinery Manufacturing Variability}, year = {2021}, number = {9}, volume = {122}, pages = {2179-2204}, doi = {10.1002/nme.6617}, journal = {International Journal for Numerical Methods in Engineering}, keywords = {Multilevel Multifidelity Monte Carlo, Uncertainty Quantification, Goalbased PCA, Adjoint Sensitivity, Manufacturing Variations}, pdf = {https://doi.org/10.1002/nme.6617}}

@ARTICLE{AR-CMGC-21-40, author = {Mouradi, R.-S. and Goeury, C. and Thual, O. and Zaoui, F. and Tassi, P. }, title = {Physically interpretable machine learning algorithm on multidimensional non-linear fields}, year = {2021}, volume = {428}, pages = {1-34}, doi = {10.1016/j.jcp.2020.110074}, journal = {Journal of Computational Physics}, pdf = {https://cerfacs.fr/wp-content/uploads/2021/03/GlobC-Article-Mouradi-Physically-interpretable-machine-learning-algorithm-on-multidimensional-2021-Elsevier.pdf}}

@ARTICLE{AR-CFD-21-26, author = {Lo Schiavo, E. and Laera, D. and Riber, E. and Gicquel, L.Y.M. and Poinsot, T. }, title = {On the impact of fuel injection angle in Euler-Lagrange Large Eddy Simulations of swirling spray flames exhibiting thermoacoustic instabilities}, year = {2021}, number = {May 2021}, volume = {227}, pages = {359-370}, doi = {10.1016/j.combustflame.2021.01.009}, journal = {Combustion and Flame}, abstract = {This study deals with the fundamental problem of combustion dynamics in gas turbine combustors operating with liquid fuel. In this framework the present work proposes the study of an academic liquid fueled combustor sensitive to thermoacoustic instabilities, simulated via high-fidelity Large Eddy Simulations. The experimental setup addressed is SICCA-spray from EM2C laboratory featuring both stable and unstable flames depending on the combustion chamber length. The proposed analysis, based on the Euler-Lagrange modeling approach, studies the impact of the spray injection angle θ on both the stable flame and the triggering of the longitudinal combustor acoustic mode when using a longer quartz tube. For the liquid injection modeling, the FIM-UR semi-empirical model is adopted with three different θ values: θ = 35◦, 45◦ and 60◦. In stable conditions, the spray angle is proven to have a negligible impact on the flame anchoring point, however, the mean flame length and fuel distribution are found to be slightly modified by the velocity at which droplets enter the combustion chamber. For the thermoacoustically unstable conditions, two well-established stable limit cycles with the same frequency and similar amplitudes are obtained when fuel is injected at θ = 45◦ and 60◦. Contrarily, the system stabilizes when θ = 35◦ pointing to the importance of the dynamics of the liquid film layer formed inside the injector for this setup. Likewise, this liquid film layer dynamics and its modeling appear critical as already suggested by previous studies on the same configuration. The detailed analysis of the thermoacoustically unstable different predictions is then performed through the investigation of the spatial fields of the local Rayleigh index obtained following the novel extension in the frequency domain of the Rayleigh criterion complemented by the application of Dynamic Mode Decomposition. It confirms that the injection angle of the liquid spray has a significant effect on the thermoacoustic response of the system. Indeed the influence of θ on the dynamics of the liquid fuel when entering the combustion chamber is proven to have an impact on the synchronization mechanism governing the liquid phase with respect to acoustics sustaining the observed limit cycles. More specifically, couplings at the liquid phase level are evidenced by introducing two novel indices correlating the fluctuations of liquid fuel volume fraction and evaporation rate with pressure.}, keywords = {Thermoacoustic instabilities, Turbulent spray flames, Large Eddy Simulations, Spray angle sensitivity, Eulerian-Lagrangian approach}, url = {https://www.sciencedirect.com/science/article/pii/S0010218021000171}}