Toroidally symmetric plasma vortex at tokamak divertor null point

doi:10.1063/1.4943101

Title: Toroidally symmetric plasma vortex at tokamak divertor null point

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Reduced MHD equations are used for studying toroidally symmetric plasma dynamics near the divertor null point. Numerical solution of these equations exhibits a plasma vortex localized at the null point with the time-evolution defined by interplay of the curvature drive, magnetic restoring force, and dissipation. Convective motion is easier to achieve for a second-order null (snowflake) divertor than for a regular x-point configuration, and the size of the convection zone in a snowflake configuration grows with plasma pressure at the null point. In conclusion, the trends in simulations are consistent with tokamak experiments which indicate the presence of enhanced transport at the null point.

Authors:

Umansky, M. V. ^[1] ; Ryutov, D. D. ^[1]

Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Publication Date:: 2016-03-09

Report Number(s):: LLNL-JRNL-680074
Journal ID: ISSN 1070-664X

Grant/Contract Number:: AC52-07NA27344

Type:: Accepted Manuscript

Journal Name:: Physics of Plasmas

Additional Journal Information:: Journal Volume: 23; Journal Issue: 3; Journal ID: ISSN 1070-664X

Publisher:: American Institute of Physics (AIP)

Research Org:: Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Sponsoring Org:: USDOE

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION; Toroidal plasma confinement; Divertors; Plasma convection; Plasma motion; Fluid equations

OSTI Identifier:: 1368023

Alternate Identifier(s):: OSTI ID: 1241397


                    Umansky, M. V., and Ryutov, D. D.. Toroidally symmetric plasma vortex at tokamak divertor null point.  United States: N. p.,  
        Web.  doi:10.1063/1.4943101.

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                    Umansky, M. V., & Ryutov, D. D.. Toroidally symmetric plasma vortex at tokamak divertor null point.  United States.  doi:10.1063/1.4943101.

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                    Umansky, M. V., and Ryutov, D. D.. 2016.  
        "Toroidally symmetric plasma vortex at tokamak divertor null point".  United States.  
        doi:10.1063/1.4943101.  https://www.osti.gov/servlets/purl/1368023.

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@article{osti_1368023,

  title        = {Toroidally symmetric plasma vortex at tokamak divertor null point},

  author       = {Umansky, M. V. and Ryutov, D. D.},

  abstractNote = {Reduced MHD equations are used for studying toroidally symmetric plasma dynamics near the divertor null point. Numerical solution of these equations exhibits a plasma vortex localized at the null point with the time-evolution defined by interplay of the curvature drive, magnetic restoring force, and dissipation. Convective motion is easier to achieve for a second-order null (snowflake) divertor than for a regular x-point configuration, and the size of the convection zone in a snowflake configuration grows with plasma pressure at the null point. In conclusion, the trends in simulations are consistent with tokamak experiments which indicate the presence of enhanced transport at the null point.},

  doi          = {10.1063/1.4943101},

  journal      = {Physics of Plasmas},

  number       = 3,

  volume       = 23,

  place        = {United States},

  year         = {2016},

  month        = {3}

}

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Title: Toroidally symmetric plasma vortex at tokamak divertor null point

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