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arXiv · 2212.07494

Second-order force scheme for lattice Boltzmann method

Xuhui Li·Wenyang Duan·Xiaowen Shan
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Abstract

We present an a priori derivation of the force scheme for lattice Boltzmann method based on kinetic theoretical formulation. We show that the discrete lattice effect, previously eliminated a posteriori in BGK collision model, is due to first-order space-time discretization and can be eliminated generically for a wide range of collision models with second-order space-time discretization. Particularly, the force scheme for the recently developed spectral multiple-relaxation-time (SMRT) collision model is obtained and numerically verified.

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Xuhui Li, Wenyang Duan, Xiaowen Shan. 2022-12-14. Second-order force scheme for lattice Boltzmann method. https://arxiv.org/abs/2212.07494

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