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arXiv · 1705.09807

A large eddy lattice Boltzmann simulation of magnetohydrodynamic turbulence

Christopher Flint·George Vahala
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Abstract

Large eddy simulations (LES) of a lattice Boltzmann magnetohydrodynamic (LB-MHD) model are performed for the unstable magnetized Kelvin-Helmholtz jet instability. This algorithm is an extension of Ansumali et. al. (2004) to MHD in which one performs first an expansion in the filter width on the kinetic equations followed by the usual low Knudsen number expansion. These two perturbation operations do not commute. Closure is achieved by invoking the physical constraint that subgrid effects occur at transport time scales. The simulations are in very good agreement with direct numerical simulations.

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Christopher Flint, George Vahala. 2017-12-18. A large eddy lattice Boltzmann simulation of magnetohydrodynamic turbulence. https://doi.org/10.1016/j.physleta.2017.12.016

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