A Partial Entropic Stabilization of Lattice Boltzmann MHD

摘要

The entropic lattice Boltzmann algorithm of Karlin et. al. is partiallyextended to magnetohydrodynamics, based on the Dellar model of introducing avector distribution for the magnetic field. This entropic ansatz is now appliedonly to the scalar particle distribution function so as to permit the manyproblems entailing magnetic field reversal. A 9-bit lattice is employed forboth particle and magnetic distributions for our two dimensional simulations.The entropic ansatz is benchmarked against our earlier multiple relaxationlattice-Boltzmann model for the Kelvin-Helmholtz instability in a magnetizedjet. Other two dimensional simulations are performed and compared to resultsdetermined by more standard direct algorithms: in particular the switch overbetween the Kelvin-Helmholtz/tearing mode instability of Chen et. al., and thegeneralized Orszag-Tang vortex model of Biskamp-Welter. Very good results areachieved.