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Statistical anisotropy of magnetohydrodynamic turbulence

Wolf-Christian Mueller·Dieter Biskamp·Roland Grappin
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Abstract

Direct numerical simulations of decaying and forced magnetohydrodynamic (MHD) turbulence without and with mean magnetic field are analyzed by higher-order two-point statistics. The turbulence exhibits statistical anisotropy with respect to the direction of the local magnetic field even in the case of global isotropy. A mean magnetic field reduces the parallel-field dynamics while in the perpendicular direction a gradual transition towards two-dimensional MHD turbulence is observed with $k^{-3/2}$ inertial-range scaling of the perpendicular energy spectrum. An intermittency model based on the Log-Poisson approach, $ζ_p=p/g^2 +1 -(1/g)^{p/g}$, is able to describe the observed structure function scalings.

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Wolf-Christian Mueller, Dieter Biskamp, Roland Grappin. 2003-06-05. Statistical anisotropy of magnetohydrodynamic turbulence. https://doi.org/10.1103/physreve.67.066302

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