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arXiv · 0901.4799

Continuum Free-Energy formulation for a class of Lattice Boltzmann multiphase models

M. Sbragaglia·H. Chen·X. Shan·S. Succi
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Abstract

It is shown that the Shan-Chen (SC) model for non-ideal lattice fluids can be made compliant with a pseudo free-energy principle by simple addition of a gradient force, whose expression is uniquely specified in terms of the fluid density. This additional term is numerically shown to provide fairly negligible effects on the system evolution during phase-separation. To the best of our knowledge, these important properties of the SC model were not noted before. The approach developed in the present work is based on a continuum analysis: further extensions, more in line with a discrete lattice theory (X. Shan, {\it Phys Rev E}, {\bf 77} 066702 (2008)) can be envisaged for the future.

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M. Sbragaglia, H. Chen, X. Shan, S. Succi. 2009-01-29. Continuum Free-Energy formulation for a class of Lattice Boltzmann multiphase models. https://doi.org/10.1209/0295-5075%2F86%2F24005

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