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arXiv · 1706.01424

A Partial Entropic Stabilization of Lattice Boltzmann MHD

Christopher Flint·George Vahala
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Abstract

The entropic lattice Boltzmann algorithm of Karlin et. al. is partially extended to magnetohydrodynamics, based on the Dellar model of introducing a vector distribution for the magnetic field. This entropic ansatz is now applied only to the scalar particle distribution function so as to permit the many problems entailing magnetic field reversal. A 9-bit lattice is employed for both particle and magnetic distributions for our two dimensional simulations. The entropic ansatz is benchmarked against our earlier multiple relaxation lattice-Boltzmann model for the Kelvin-Helmholtz instability in a magnetized jet. Other two dimensional simulations are performed and compared to results determined by more standard direct algorithms: in particular the switch over between the Kelvin-Helmholtz/tearing mode instability of Chen et. al., and the generalized Orszag-Tang vortex model of Biskamp-Welter. Very good results are achieved.

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Christopher Flint, George Vahala. 2017-12-20. A Partial Entropic Stabilization of Lattice Boltzmann MHD. https://doi.org/10.1103/physreve.97.013302

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