Regularized characteristic boundary conditions for the Lattice-Boltzmann methods at high Reynolds number flows

JOURNAL OF COMPUTATIONAL PHYSICS

卷:331

Article

Wissocq, Gauthier^1,2,3  Gourdain, Nicolas¹  Malaspinas, Orestis⁴  Eyssartier, Alexandre² 

[1] ISAE, Dept Aerodynam Energet & Prop, Toulouse, France

[2] Altran, DO ME, Blagnac, France

[3] CERFACS, CFD Team, 42 Ave Gaspard Coriolis, F-31057 Toulouse 01, France

[4] Univ Geneva, SPC Ctr Univ Informat, 7 Route Drize, CH-1227 Geneva, Switzerland

关键词: Lattice Boltzmann method;    Characteristic boundary conditions;    LODI;    High Reynolds number flows;   

DOI  :  10.1016/j.jcp.2016.11.037

来源: Elsevier

【 摘 要 】

This paper reports the investigations done to adapt the Characteristic Boundary Conditions (CBC) to the Lattice-Boltzmann formalism for high Reynolds number applications. Three CBC formalisms are implemented and tested in an open source LBM code: the baseline local one-dimension inviscid (BL-LODI) approach, its extension including the effects of the transverse terms (CBC-2D) and a local streamline approach in which the problem is reformulated in the incident wave framework (LS-LODI). Then all implementations of the CBC methods are tested for a variety of test cases, ranging from canonical problems (such as 2D plane and spherical waves and 2D vortices) to a 2D NACA profile at high Reynolds number (Re =10(5)), representative of aeronautic applications. The LS-LODI approach provides the best results for pure acoustics waves (plane and spherical waves). However, it is not well suited to the outflow of a convected vortex for which the CBC-2D associated with a relaxation on density and transverse waves provides the best results. As regards numerical stability, a regularized adaptation is necessary to simulate high Reynolds number flows. The so-called regularized FD (Finite Difference) adaptation, a modified regularized approach where the off-equilibrium part of the stress tensor is computed thanks to a finite difference scheme, is the only tested adaptation that can handle the high Reynolds computation. (C) 2016 Elsevier Inc. All rights reserved.

【 授权许可】

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