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arXiv · 1608.01906

Evaluation of the Finite Element Lattice Boltzmann Method for Binary Fluid Flows

Rastin Matin·Marek Krzysztof Misztal·Anier Hernandez-Garcia·Joachim Mathiesen
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Abstract

In contrast to the commonly used lattice Boltzmann method, off-lattice Boltzmann methods decouple the velocity discretization from the underlying spatial grid, thus allowing for more efficient geometric representations of complex boundaries. The current work combines characteristic-based integration of the streaming step with the free-energy based multiphase model by Lee et. al. [Journal of Computational Physics, 206 (1), 2005 ]. This allows for simulation time steps more than an order of magnitude larger than the relaxation time. Unlike previous work by Wardle et. al. [Computers and Mathematics with Applications, 65 (2), 2013 ] that integrated intermolecular forcing terms in the advection term, the current scheme applies collision and forcing terms locally for a simpler finite element formulation. A series of thorough benchmark studies reveal that this does not compromise stability and that the scheme is able to accurately simulate flows at large density and viscosity contrasts.

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Rastin Matin, Marek Krzysztof Misztal, Anier Hernandez-Garcia, Joachim Mathiesen. 2016-08-05. Evaluation of the Finite Element Lattice Boltzmann Method for Binary Fluid Flows. https://arxiv.org/abs/1608.01906

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