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arXiv · 2203.01380

Over-Relaxation in Diffusive Integer Lattice Gas

Kyle Strand·Alexander J. Wagner
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Abstract

One of the most striking draw-backs of standard lattice gas methods over lattice Boltzmann methods is a much more limited range of transport parameters that can be achieved. It is common for lattice Boltzmann methods to use over-relaxation to achieve arbitrarily small transport parameters in the hydrodynamic equations. Here, we show that it is possible to implement over-relaxation for integer lattice gases. For simplicity we focus here on lattice gases for the diffusion equation. We demonstrate that adding a flipping operation to lattice gases results in a multi-relaxation time lattice Boltzmann scheme with over-relaxation in the Boltzmann limit.

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Kyle Strand, Alexander J. Wagner. 2022-03-02. Over-Relaxation in Diffusive Integer Lattice Gas. https://doi.org/10.1103/physreve.105.l063301

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