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

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 Alfvén 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.

5 figures, 1 table, appear in PRE

References in corpus (3)

• Development of Anisotropy in Incompressible Magnetohydrodynamic Turbulence
• Role of Cross Helicity in Cascade Processes of MHD turbulence
• Phenomenology of turbulent dynamo growth and saturation