Toroidally symmetric plasma vortex at tokamak divertor null point
Abstract
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 timeevolution defined by interplay of the curvature drive, magnetic restoring force, and dissipation. Convective motion is easier to achieve for a secondorder null (snowflake) divertor than for a regular xpoint 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:

 Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
 Publication Date:
 Research Org.:
 Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1368023
 Alternate Identifier(s):
 OSTI ID: 1241397
 Report Number(s):
 LLNLJRNL680074
Journal ID: ISSN 1070664X
 Grant/Contract Number:
 AC5207NA27344
 Resource Type:
 Accepted Manuscript
 Journal Name:
 Physics of Plasmas
 Additional Journal Information:
 Journal Volume: 23; Journal Issue: 3; Journal ID: ISSN 1070664X
 Publisher:
 American Institute of Physics (AIP)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION; Toroidal plasma confinement; Divertors; Plasma convection; Plasma motion; Fluid equations
Citation Formats
Umansky, M. V., and Ryutov, D. D. Toroidally symmetric plasma vortex at tokamak divertor null point. United States: N. p., 2016.
Web. https://doi.org/10.1063/1.4943101.
Umansky, M. V., & Ryutov, D. D. Toroidally symmetric plasma vortex at tokamak divertor null point. United States. https://doi.org/10.1063/1.4943101
Umansky, M. V., and Ryutov, D. D. Wed .
"Toroidally symmetric plasma vortex at tokamak divertor null point". United States. https://doi.org/10.1063/1.4943101. https://www.osti.gov/servlets/purl/1368023.
@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 timeevolution defined by interplay of the curvature drive, magnetic restoring force, and dissipation. Convective motion is easier to achieve for a secondorder null (snowflake) divertor than for a regular xpoint 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}
}
Web of Science
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Works referencing / citing this record:
Turbulence and flows in the plasma boundary of snowflake magnetic configurations
journal, January 2020
 Giacomin, M.; Stenger, L. N.; Ricci, P.
 Nuclear Fusion, Vol. 60, Issue 2
Developing physics basis for the snowflake divertor in the DIIID tokamak
journal, February 2018
 Soukhanovskii, V. A.; Allen, S. L.; Fenstermacher, M. E.
 Nuclear Fusion, Vol. 58, Issue 3
The effect of the secondary xpoint on the scrapeoff layer transport in the TCV snowflake minus divertor
journal, December 2018
 Maurizio, R.; Tsui, C. K.; Duval, B. P.
 Nuclear Fusion, Vol. 59, Issue 1