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arXiv · 1009.0254

Thermal fluctuations in the lattice Boltzmann method for non-ideal fluids

M. Gross·R. Adhikari·M. E. Cates·F. Varnik
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Abstract

We introduce thermal fluctuations in the lattice Boltzmann method for non-ideal fluids. A fluctuation-dissipation theorem is derived within the Langevin framework and applied to a specific lattice Boltzmann model that approximates the linearized fluctuating Navier-Stokes equations for fluids based on square-gradient free energy functionals. The obtained thermal noise is shown to ensure equilibration of all degrees of freedom in a simulation to high accuracy. Furthermore, we demonstrate that satisfactory results for most practical applications of fluctuating hydrodynamics can already be achieved using thermal noise derived in the long wavelength-limit.

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M. Gross, R. Adhikari, M. E. Cates, F. Varnik. 2010-09-01. Thermal fluctuations in the lattice Boltzmann method for non-ideal fluids. https://doi.org/10.1103/physreve.82.056714

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