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arXiv · 1009.3549

Cascades and dissipation ratio in rotating MHD turbulence at low magnetic Prandtl number

Franck Plunian·Rodion Stepanov
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Abstract

A phenomenology of isotropic magnetohydrodynamic turbulence subject to both rotation and applied magnetic field is presented. It is assumed that the triple correlations decay-time is the shortest between the eddy turn-over time and the ones associated to the rotating frequency and Alfv\'en wave period. For $Pm=1$ it leads to four kinds of piecewise spectra, depending on the four parameters, injection rate of energy, magnetic diffusivity, rotation rate and applied field. With a shell model of MHD turbulence (including rotation and applied magnetic field), spectra for $Pm \le 1$ are presented, together with the ratio between magnetic and viscous dissipation.

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Franck Plunian, Rodion Stepanov. 2010-09-18. Cascades and dissipation ratio in rotating MHD turbulence at low magnetic Prandtl number. https://doi.org/10.1103/physreve.82.046311

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