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arXiv · 1311.1922

Discrete Filters for Large Eddy Simulation of Forced Compressible MHD Turbulence

Alexander A. Chernyshov·Kirill. V. Karelsky·Arakel. S. Petrosyan
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Abstract

In present study, we discuss results of applicability of discrete filters for large eddy simulation (LES) method of forced compressible magnetohydrodynamic (MHD) turbulent flows with the scale-similarity model. Influences and effects of discrete filter shapes on the scale-similarity model are examined in physical space using a finite-difference numerical schemes. We restrict ourselves to the Gaussian filter and the top-hat filter. Representations of this subgrid-scale model which correspond to various 3- and 5-point approximations of both Gaussian and top-hat filters for different values of parameter $ε$ (the ratio of the mesh size to the cut-off lengthscale of the filter) are investigated. Discrete filters produce more discrepancies for magnetic field. It is shown that the Gaussian filter is more sensitive to the parameter $ε$ than the top-hat filter in compressible forced MHD turbulence. The 3-point filters at $ε=2$ and $ε=3$ give the least accurate results and the 5-point Gaussian filter shows the best results at $ε=2$.

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Alexander A. Chernyshov, Kirill. V. Karelsky, Arakel. S. Petrosyan. 2013-11-08. Discrete Filters for Large Eddy Simulation of Forced Compressible MHD Turbulence. https://arxiv.org/abs/1311.1922

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