Zonal flow formation in the presence of ambient mean shear

Hsu, Pei-Chun; Diamond, P. H.

doi:10.1063/1.4907905

Title: Zonal flow formation in the presence of ambient mean shear

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Abstract

The effect of mean shear flows on zonal flow formation is considered in the contexts of plasma drift wave turbulence and quasi-geostrophic turbulence models. The generation of zonal flows by modulational instability in the presence of large-scale mean shear flows is studied using the method of characteristics as applied to the wave kinetic equation. It is shown that mean shear flows reduce the modulational instability growth rate by shortening the coherency time of the wave spectrum with the zonal shear. The scalings of zonal flow growth rate and turbulent vorticity flux with mean shear are determined in the strong shear limit.

Authors:

Hsu, Pei-Chun; Diamond, P. H. ^[1]

Center for Astrophysics and Space Sciences and Department of Physics, University of California San Diego, La Jolla, California 92093-0424 (United States)

Publication Date:: Sun Feb 15 00:00:00 EST 2015

OSTI Identifier:: 22408089

Resource Type:: Journal Article

Journal Name:: Physics of Plasmas

Additional Journal Information:: Journal Volume: 22; Journal Issue: 2; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1070-664X

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; INSTABILITY GROWTH RATES; KINETIC EQUATIONS; PLASMA DRIFT; PLASMA INSTABILITY; SHEAR; TURBULENCE

Citation Formats


                    Hsu, Pei-Chun, and Diamond, P. H. Zonal flow formation in the presence of ambient mean shear.  United States: N. p., 2015. 
        Web.  doi:10.1063/1.4907905.

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                    Hsu, Pei-Chun, & Diamond, P. H. Zonal flow formation in the presence of ambient mean shear.  United States.  https://doi.org/10.1063/1.4907905

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                    Hsu, Pei-Chun, and Diamond, P. H. 2015.  
        "Zonal flow formation in the presence of ambient mean shear".  United States.  https://doi.org/10.1063/1.4907905.

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@article{osti_22408089,

  title        = {Zonal flow formation in the presence of ambient mean shear},

  author       = {Hsu, Pei-Chun and Diamond, P. H.},

  abstractNote = {The effect of mean shear flows on zonal flow formation is considered in the contexts of plasma drift wave turbulence and quasi-geostrophic turbulence models. The generation of zonal flows by modulational instability in the presence of large-scale mean shear flows is studied using the method of characteristics as applied to the wave kinetic equation. It is shown that mean shear flows reduce the modulational instability growth rate by shortening the coherency time of the wave spectrum with the zonal shear. The scalings of zonal flow growth rate and turbulent vorticity flux with mean shear are determined in the strong shear limit.},

  doi          = {10.1063/1.4907905},

  url          = {https://www.osti.gov/biblio/22408089},
  journal      = {Physics of Plasmas},

  issn         = {1070-664X},

  number       = 2,

  volume       = 22,

  place        = {United States},

  year         = {Sun Feb 15 00:00:00 EST 2015},

  month        = {Sun Feb 15 00:00:00 EST 2015}

}

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