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arXiv · 1803.00437

Lattice Boltzmann model approximated with finite difference expressions

François Dubois·Pierre Lallemand·Christian Obrecht·Mohamed Tekitek
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Abstract

We show that the asymptotic properties of the link-wise artificial compressibility method are not compatible with a correct approximation of fluid properties. We propose to adapt the previous method through a framework suggested by the Taylor expansion method and to replace first order terms in the expansion by appropriate three or five points finite differences and to add non linear terms. The "FD-LBM" scheme obtained by this method is tested in two dimensions for shear wave, Stokes modes and Poiseuille flow. The results are compared with the usual lattice Boltzmann method in the framework of multiple relaxation times.

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François Dubois, Pierre Lallemand, Christian Obrecht, Mohamed Tekitek. 2018-03-01. Lattice Boltzmann model approximated with finite difference expressions. https://arxiv.org/abs/1803.00437

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