Abstract
Spectral direct numerical simulations of incompressible MHD turbulence at a resolution of up to collocation points are presented for a statistically isotropic system as well as for a setup with an imposed strong mean magnetic field. The spectra of residual energy, , and total energy, , are observed to scale self-similarly in the inertial range as , (isotropic case) and , (anisotropic case, perpendicular to the mean field direction). A model of dynamic equilibrium between kinetic and magnetic energy, based on the corresponding evolution equations of the eddy-damped quasinormal Markovian closure approximation, explains the findings. The assumed interplay of turbulent dynamo and Alfvén effect yields , which is confirmed by the simulations.
- Received 21 February 2005
DOI:https://doi.org/10.1103/PhysRevLett.95.114502
©2005 American Physical Society