Stable compression of a spherical tokamak plasma
Abstract
In this study, an analysis of toroidal plasma compression by a collapsing flux conserver reveals linearly stable scenarios of operation to high compression ratios. The resistive and ideal MHD stability is calculated in full toroidal geometry using the asymptotic matching method in realistic conditions. A time dependent MHD simulation of the compression is conducted to confirm the conservation principles used to calculate the equilibrium states for the analysis. The near edge current profile, controlled by toroidal field ramping during compression, is shown to be critical to stability due to coupling between poloidal components of the least stable mode. Two cases with slight differences in edge current are examined, one with a stable corridor to high compression and one without.
 Authors:

 Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
 General Fusion Inc., Burnaby, BC (Canada)
 Publication Date:
 Research Org.:
 Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1650654
 Grant/Contract Number:
 AC0209CH11466
 Resource Type:
 Accepted Manuscript
 Journal Name:
 Nuclear Fusion
 Additional Journal Information:
 Journal Volume: 60; Journal Issue: 4; Journal ID: ISSN 00295515
 Publisher:
 IOP Science
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY
Citation Formats
Brennan, Dylan, Froese, Aaron, Reynolds, Meritt, Barsky, Sandra, Wang, Zhirui, Delage, Michael, and Laberge, Michel. Stable compression of a spherical tokamak plasma. United States: N. p., 2020.
Web. https://doi.org/10.1088/17414326/ab74a2.
Brennan, Dylan, Froese, Aaron, Reynolds, Meritt, Barsky, Sandra, Wang, Zhirui, Delage, Michael, & Laberge, Michel. Stable compression of a spherical tokamak plasma. United States. https://doi.org/10.1088/17414326/ab74a2
Brennan, Dylan, Froese, Aaron, Reynolds, Meritt, Barsky, Sandra, Wang, Zhirui, Delage, Michael, and Laberge, Michel. Thu .
"Stable compression of a spherical tokamak plasma". United States. https://doi.org/10.1088/17414326/ab74a2. https://www.osti.gov/servlets/purl/1650654.
@article{osti_1650654,
title = {Stable compression of a spherical tokamak plasma},
author = {Brennan, Dylan and Froese, Aaron and Reynolds, Meritt and Barsky, Sandra and Wang, Zhirui and Delage, Michael and Laberge, Michel},
abstractNote = {In this study, an analysis of toroidal plasma compression by a collapsing flux conserver reveals linearly stable scenarios of operation to high compression ratios. The resistive and ideal MHD stability is calculated in full toroidal geometry using the asymptotic matching method in realistic conditions. A time dependent MHD simulation of the compression is conducted to confirm the conservation principles used to calculate the equilibrium states for the analysis. The near edge current profile, controlled by toroidal field ramping during compression, is shown to be critical to stability due to coupling between poloidal components of the least stable mode. Two cases with slight differences in edge current are examined, one with a stable corridor to high compression and one without.},
doi = {10.1088/17414326/ab74a2},
journal = {Nuclear Fusion},
number = 4,
volume = 60,
place = {United States},
year = {2020},
month = {3}
}
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