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Title: Nonlinear damping of zonal flows

Abstract

The modulatonal instability theory for the generation of large-scale (zonal) modes by drift modes has been extended to the second order including the effects of finite amplitude zonal flows, ϕ{sub q}. The nonlinear (second-order) sidebands are included in the perturbative expansion to derive the nonlinear equation for the evolution of ϕ{sub q}. It is shown that effects of finite ϕ{sub q} reduce the growth rate of zonal flow with a possibility of oscillatory regimes at a later stage.

Authors:
;  [1];  [2]
  1. University of Saskatchewan, Department of Physics and Engineering Physics (Canada)
  2. Instituto Superior Técnico, Instituto de Plasmas e Fusão Nuclear (Portugal)
Publication Date:
OSTI Identifier:
22614094
Resource Type:
Journal Article
Resource Relation:
Journal Name: Plasma Physics Reports; Journal Volume: 42; Journal Issue: 8; Other Information: Copyright (c) 2016 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AMPLITUDES; DAMPING; EQUATIONS; NONLINEAR PROBLEMS; PLASMA INSTABILITY

Citation Formats

Koshkarov, O., E-mail: koshkarov.alexandr@usask.ca, Smolyakov, A. I., and Mendonca, J. T. Nonlinear damping of zonal flows. United States: N. p., 2016. Web. doi:10.1134/S1063780X16080067.
Koshkarov, O., E-mail: koshkarov.alexandr@usask.ca, Smolyakov, A. I., & Mendonca, J. T. Nonlinear damping of zonal flows. United States. doi:10.1134/S1063780X16080067.
Koshkarov, O., E-mail: koshkarov.alexandr@usask.ca, Smolyakov, A. I., and Mendonca, J. T. 2016. "Nonlinear damping of zonal flows". United States. doi:10.1134/S1063780X16080067.
@article{osti_22614094,
title = {Nonlinear damping of zonal flows},
author = {Koshkarov, O., E-mail: koshkarov.alexandr@usask.ca and Smolyakov, A. I. and Mendonca, J. T.},
abstractNote = {The modulatonal instability theory for the generation of large-scale (zonal) modes by drift modes has been extended to the second order including the effects of finite amplitude zonal flows, ϕ{sub q}. The nonlinear (second-order) sidebands are included in the perturbative expansion to derive the nonlinear equation for the evolution of ϕ{sub q}. It is shown that effects of finite ϕ{sub q} reduce the growth rate of zonal flow with a possibility of oscillatory regimes at a later stage.},
doi = {10.1134/S1063780X16080067},
journal = {Plasma Physics Reports},
number = 8,
volume = 42,
place = {United States},
year = 2016,
month = 8
}
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