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Title: Toroidally symmetric plasma vortex at tokamak divertor null point

Journal Article · · Physics of Plasmas
DOI: https://doi.org/10.1063/1.4943101 · OSTI ID:1368023
 [1];  [1]
  1. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

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.

Research Organization:
Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
Sponsoring Organization:
USDOE
Grant/Contract Number:
AC52-07NA27344
OSTI ID:
1368023
Alternate ID(s):
OSTI ID: 1241397
Report Number(s):
LLNL-JRNL--680074
Journal Information:
Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 3 Vol. 23; ISSN 1070-664X
Publisher:
American Institute of Physics (AIP)Copyright Statement
Country of Publication:
United States
Language:
English

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Cited By (3)

Turbulence and flows in the plasma boundary of snowflake magnetic configurations journal January 2020
The effect of the secondary x-point on the scrape-off layer transport in the TCV snowflake minus divertor journal December 2018
Developing physics basis for the snowflake divertor in the DIII-D tokamak journal February 2018