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arXiv · 2012.11075

Well-balanced lattice Boltzmann equation for two-phase flows

Zhaoli Guo
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Abstract

The standard lattice Boltzmann equation (LBE) method usually fails to capture the physical equilibrium state of a two-phase fluid system, i.e., zero velocity and constant chemical potential. Consequently, spurious velocities and inconsistent thermodynamic density properties are frequently encountered in LBE simulations. In this work, based on a rigorous analysis of the discrete balance equation of LBE, we identify the structure of the force imbalance due to discretization errors from different parts. Then a well-balanced LBE is proposed which can achieve the discrete equilibrium state. The well-balanced properties of the LBE are confirmed by some numerical tests of a flat interface problem and a droplet system.

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Zhaoli Guo. 2020-12-21. Well-balanced lattice Boltzmann equation for two-phase flows. https://doi.org/10.1063/5.0041446

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