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arXiv · 1806.10202

Fully resolved array of simulations investigating the influence of the magnetic Prandtl number on magnetohydrodynamic turbulence

Mairi E. McKay·Arjun Berera·Richard D. J. G. Ho
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Abstract

We explore the effect of the magnetic Prandtl number Pm on energy and dissipation in fully resolved direct numerical simulations of steady-state, mechanically forced homogeneous magnetohydrodynamic turbulence in the range Pm = 1/32 to 32. We compare the spectra and show that if the simulations are not fully resolved, the steepness of the scaling of the kinetic-to-magnetic dissipation ratio with Pm is overestimated. We also present results of decaying turbulence with helical and nonhelical magnetic fields, where we find nonhelical reverse spectral transfer for Pm < 1. The results of this systematic analysis have applications including stars, planetary dynamos, and accretion disks.

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Mairi E. McKay, Arjun Berera, Richard D. J. G. Ho. 2019-01-15. Fully resolved array of simulations investigating the influence of the magnetic Prandtl number on magnetohydrodynamic turbulence. https://doi.org/10.1103/physreve.99.013101

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