Three-dimensional electromagnetic strong turbulence. I. Scalings, spectra, and field statistics

Journal Article · Wed Jun 15 04:00:00 EDT 2011 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.3592147· OSTI ID:21546945

Graham, D B; Robinson, P A; Cairns, Iver H ^[1]; Skjaeraasen, O ^[2]

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1. School of Physics, University of Sydney, New South Wales 2006 (Australia)
2. ProsTek, Institute for Energy Technology, P.O. Box 40, N-2027 Kjeller (Norway)

The first fully three-dimensional (3D) simulations of large-scale electromagnetic strong turbulence (EMST) are performed by numerically solving the electromagnetic Zakharov equations for electron thermal speeds {nu}{sub e} with {nu}{sub e}/c{>=}0.025. The results of these simulations are presented, focusing on scaling behavior, energy density spectra, and field statistics of the Langmuir (longitudinal) and transverse components of the electric fields during steady-state strong turbulence, where multiple wave packets collapse simultaneously and the system is approximately statistically steady in time. It is shown that for {nu}{sub e}/c > or approx. 0.17 strong turbulence is approximately electrostatic and can be explained using the electrostatic two-component model. For v{sub e}/c > or approx. 0.17 the power-law behaviors of the scalings, spectra, and field statistics differ from the electrostatic predictions and results because {nu}{sub e}/c is sufficiently high to allow transverse modes to become trapped in density wells. The results are compared with those of past 3D electrostatic strong turbulence (ESST) simulations and 2D EMST simulations. For number density perturbations, the scaling behavior, spectra, and field statistics are shown to be only weakly dependent on {nu}{sub e}/c, whereas the Langmuir and transverse scalings, spectra, and field statistics are shown to be strongly dependent on {nu}{sub e}/c. Three-dimensional EMST is shown to have features in common with 2D EMST, such as a two-component structure and trapping of transverse modes which are dependent on {nu}{sub e}/c.

• OSTI ID: 21546945
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 6 Vol. 18; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
DISTURBANCES
ENERGY DENSITY
PLASMA DENSITY
PLASMA SIMULATION
SCALING
SIMULATION
SPECTRA
STEADY-STATE CONDITIONS
THREE-DIMENSIONAL CALCULATIONS
TURBULENCE
WAVE PACKETS