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arXiv · 0712.2247

Lattice Boltzmann method for inhomogeneous fluids

S. Melchionna·U. Marini Bettolo Marconi
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Abstract

We present a lattice-based numerical method to describe the non equilibrium behavior of a simple fluid under non-uniform spatial conditions. The evolution equation for the one-particle phase-space distribution function is derived starting from a microscopic description of the system. It involves a series of approximations which are similar to those employed in theories of inhomogeneous fluids, such as Density Functional theory. Among the merits of the present approach: the possibility to determine the equation of state of the model, the transport coefficients and to provide an efficient method of numerical solution under non-uniform conditions. The algorithm is tested in a particular non equilibrium situation, namely the steady flow of a hard-sphere fluid across a narrow slit. Pronounced non-hydrodynamic oscillations in the density and velocity profiles are found.

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BibTeXRIS

S. Melchionna, U. Marini Bettolo Marconi. 2007-12-13. Lattice Boltzmann method for inhomogeneous fluids. https://doi.org/10.1209/0295-5075/81/34001

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