Mean sheared flow and parallel ion motion effects on zonal flow generation in ion-temperature-gradient mode turbulence

doi:https://doi.org/10.1063/1.2357892

Title: Mean sheared flow and parallel ion motion effects on zonal flow generation in ion-temperature-gradient mode turbulence

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Abstract

The present work investigates the direct interaction of sheared mean flow with zonal flows (ZFs) and the effect of parallel ion motion on ZF generation in ion-temperature-gradient (ITG) background turbulence. An analytical model for the direct interaction of sheared mean flows with zonal flows is constructed. The model used for the toroidal ITG driven mode is based on the equations for ion continuity, ion temperature and parallel ion motion, whereas the ZF evolution is described by the vorticity equation. The behavior of the ZF growth rate and real frequency is examined for typical tokamak parameters. It is shown that in general the zonal flow growth rate is suppressed by the presence of a sheared mean flow. In addition, with parallel ion motion effects the ZFs become more oscillatory for increasing {eta}{sub i}(=L{sub n}/L{sub Ti}) value.

Authors:

Anderson, J; Kishimoto, Y ^[1]

Department of Fundamental Energy Science, Graduate School of Energy Science, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)

Publication Date:: 2006-10-15

OSTI Identifier:: 20860295

Resource Type:: Journal Article

Journal Name:: Physics of Plasmas

Additional Journal Information:: Journal Volume: 13; Journal Issue: 10; Other Information: DOI: 10.1063/1.2357892; (c) 2006 American Institute of Physics; 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; ELECTRON TEMPERATURE; ION TEMPERATURE; PLASMA; PLASMA CONFINEMENT; PLASMA INSTABILITY; PLASMA WAVES; RADIATION TRANSPORT; SHEAR; TEMPERATURE GRADIENTS; TOKAMAK DEVICES; TURBULENCE; VORTICES

Citation Formats


                    Anderson, J, and Kishimoto, Y. Mean sheared flow and parallel ion motion effects on zonal flow generation in ion-temperature-gradient mode turbulence.  United States: N. p., 2006. 
        Web.  doi:10.1063/1.2357892.

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                    Anderson, J, & Kishimoto, Y. Mean sheared flow and parallel ion motion effects on zonal flow generation in ion-temperature-gradient mode turbulence.  United States.  https://doi.org/10.1063/1.2357892

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                    Anderson, J, and Kishimoto, Y. Sun .  
        "Mean sheared flow and parallel ion motion effects on zonal flow generation in ion-temperature-gradient mode turbulence".  United States.  https://doi.org/10.1063/1.2357892.

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@article{osti_20860295,

  title        = {Mean sheared flow and parallel ion motion effects on zonal flow generation in ion-temperature-gradient mode turbulence},

  author       = {Anderson, J and Kishimoto, Y},

  abstractNote = {The present work investigates the direct interaction of sheared mean flow with zonal flows (ZFs) and the effect of parallel ion motion on ZF generation in ion-temperature-gradient (ITG) background turbulence. An analytical model for the direct interaction of sheared mean flows with zonal flows is constructed. The model used for the toroidal ITG driven mode is based on the equations for ion continuity, ion temperature and parallel ion motion, whereas the ZF evolution is described by the vorticity equation. The behavior of the ZF growth rate and real frequency is examined for typical tokamak parameters. It is shown that in general the zonal flow growth rate is suppressed by the presence of a sheared mean flow. In addition, with parallel ion motion effects the ZFs become more oscillatory for increasing {eta}{sub i}(=L{sub n}/L{sub Ti}) value.},

  doi          = {10.1063/1.2357892},

  url          = {https://www.osti.gov/biblio/20860295},
  journal      = {Physics of Plasmas},

  issn         = {1070-664X},

  number       = 10,

  volume       = 13,

  place        = {United States},

  year         = {2006},

  month        = {10}

}

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