Integer Lattice Gas with a sampling collision operator for the fluctuating Diffusion Equation

Noah Seekins; Alexander J. Wagner

doi:10.1103/physreve.105.035303

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arXiv · 2105.13104

Integer Lattice Gas with a sampling collision operator for the fluctuating Diffusion Equation

Noah Seekins·Alexander J. Wagner

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Abstract

We developed an integer lattice gas method for the fluctuating diffusion equation. Such a method is unconditionally stable and able to recover the Poisson distribution for the microscopic densities. A key advance for integer lattice gases introduced in this paper is a new sampling collision operator that replaces particle collisions with sampling from an equilibrium distribution. This can increase the efficiency of our integer lattice gas by several orders of magnitude.

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Noah Seekins, Alexander J. Wagner. 2021-05-27. Integer Lattice Gas with a sampling collision operator for the fluctuating Diffusion Equation. https://doi.org/10.1103/physreve.105.035303

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