A finite-difference lattice Boltzmann approach for gas microflows

G. P. Ghiroldi; L. Gibelli

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arXiv · 1308.0692

A finite-difference lattice Boltzmann approach for gas microflows

G. P. Ghiroldi·L. Gibelli

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Abstract

Finite-difference Lattice Boltzmann (LB) models are proposed for simulating gas flows in devices with microscale geometries. The models employ the roots of half-range Gauss-Hermite polynomials as discrete velocities. Unlike the standard LB velocity-space discretizations based on the roots of full-range Hermite polynomials, using the nodes of a quadrature defined in the half-space permits a consistent treatment of kinetic boundary conditions. The possibilities of the proposed LB models are illustrated by studying the one-dimensional Couette flow and the two-dimensional driven cavity flow. Numerical and analytical results show an improved accuracy in finite Knudsen flows as compared with standard LB models.

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G. P. Ghiroldi, L. Gibelli. 2013-08-03. A finite-difference lattice Boltzmann approach for gas microflows. https://arxiv.org/abs/1308.0692

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