Shell Models for Magnetohydrodynamic Turbulence

Multiscaling in Models of Magnetohydrodynamic Turbulence

From a numerical study of the magnetohydrodynamic (MHD) equations we show, for the first time in three dimensions sd ­ 3d, that velocity and magnetic-field structure functions exhibit multiscaling, extended self-similarity (ESS), and generalized extended self-similarity (GESS). We propose a new shell model for homogeneous and isotropic MHD turbulence, which preserves all the invariants of ideal...

A non-local shell model of hydrodynamic and magnetohydrodynamic turbulence

Dynamic multiscaling in magnetohydrodynamic turbulence.

We present a study of the multiscaling of time-dependent velocity and magnetic-field structure functions in homogeneous, isotropic magnetohydrodynamic (MHD) turbulence in three dimensions. We generalize the formalism that has been developed for analogous studies of time-dependent structure functions in fluid turbulence to MHD. By carrying out detailed numerical studies of such time-dependent st...

Magnetohydrodynamic turbulence in supernova remnants

We present estimates of the angular power spectra of the synchrotron radiation intensity fluctuations at 6 and 20 cm for the shell type supernova remnant Cas A and the filled-centre Crab supernova remnant. We find that the intensity fluctuations of both sources have a power law power spectrum with index −3.24 ± 0.03. This power law power spectrum is consistent with the magnetohydrodynamic turbu...

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

A phenomenology of isotropic magnetohydrodynamic (MHD) turbulence subject to both rotation and applied magnetic field is presented. It is assumed that the triple correlation decay time is the shortest between the eddy turn-over time and the ones associated to the rotating frequency and the Alfvén wave period. For Pm=1 it leads to four kinds of piecewise spectra, depending on four parameters: in...