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arXiv · 1803.11345

Central-moments-based lattice Boltzmann scheme for coupled Cahn-Hilliard-Navier-Stokes equations

Alessandro De Rosis·Shimpei Saito·Akiko Kaneko·Yutaka Abe
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Abstract

In this paper, we propose a lattice Boltzmann (LB) model to solve the coupled Cahn-Hilliard-Navier-Stokes equations. Differently from previous efforts, the LB equation for the fluid velocity is decomposed in a space of non-orthogonal central moments where the surface tension force is inserted directly in the equilibrium state. The present scheme is validated against well-consolidated benchmark tests, showing very good accuracy. Moreover, it outperforms the BGK approach in terms of stability, as our algorithm allows us to simulate a very large range of viscosity contrast.

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Alessandro De Rosis, Shimpei Saito, Akiko Kaneko, Yutaka Abe. 2018-03-30. Central-moments-based lattice Boltzmann scheme for coupled Cahn-Hilliard-Navier-Stokes equations. https://arxiv.org/abs/1803.11345

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