Forward and inverse cascades in decaying two-dimensional electron magnetohydrodynamic turbulence

Journal Article · Wed Apr 15 04:00:00 EDT 2009 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.3111033· OSTI ID:21276986

Wareing, C J; Hollerbach, R ^[1]

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1. Department of Applied Mathematics, University of Leeds, Leeds LS2 9JT (United Kingdom)

Electron magnetohydrodynamic (EMHD) turbulence in two dimensions is studied via high-resolution numerical simulations with a normal diffusivity. The resulting energy spectra asymptotically approach a k{sup -5/2} law with increasing R{sub B}, the ratio of the nonlinear to linear time scales in the governing equation. No evidence is found of a dissipative cutoff, consistent with nonlocal spectral energy transfer. Dissipative cutoffs found in previous studies are explained as artificial effects of hyperdiffusivity. Relatively stationary structures are found to develop in time, rather than the variability found in ordinary or MHD turbulence. Further, EMHD turbulence displays scale-dependent anisotropy with reduced energy transfer in the direction parallel to the uniform background field, consistent with previous studies. Finally, the governing equation is found to yield an inverse cascade, at least partially transferring magnetic energy from small to large scales.

• OSTI ID: 21276986
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 4 Vol. 16; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
DIFFUSION
ELECTRONS
ENERGY SPECTRA
ENERGY TRANSFER
MAGNETOHYDRODYNAMICS
PLASMA
PLASMA SIMULATION
TURBULENCE
TWO-DIMENSIONAL CALCULATIONS