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Title: Drift kinetic effects on the plasma response in high beta spherical tokamak experiments

Abstract

The high β plasma response to rotating n = 1 external magnetic perturbations is numerically studied and compared with the National Spherical Torus Experiment (NSTX). The hybrid magnetohydrodynamic(MHD)-kinetic modeling shows that drift kinetic effects are important in resolving the disagreement of plasma response between the ideal MHD prediction and the NSTX experimental observation when plasma pressure reaches and exceeds the no-wall limit. Since the external rotating fields and high plasma rotation are presented in the NSTX experiments, the importance of the resistive wall effect and plasma rotation in determining the plasma response is also identified, where the resistive wall suppresses the plasma response through the wall eddy current. The inertial energy due to plasma rotation destabilizes the plasma. In conclusion, the complexity of the plasma response in this study indicates that MHD modeling, including comprehensive physics, e.g. the drift kinetic effects, resistive wall and plasma rotation, are essential in order to reliably predict the plasma behavior in a high beta spherical tokamak device.

Authors:
ORCiD logo [1];  [1]; ORCiD logo [1];  [2];  [1];  [1]
  1. Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
  2. General Atomics, San Diego, CA (United States)
Publication Date:
Research Org.:
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1395003
Report Number(s):
PPPL-5442
Journal ID: ISSN 0029-5515
Grant/Contract Number:
AC02-09CH11466
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nuclear Fusion
Additional Journal Information:
Journal Volume: 58; Journal Issue: 1; Journal ID: ISSN 0029-5515
Publisher:
IOP Science
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; kinetic effects; plasma response; spherical tokamak; NSTX

Citation Formats

Wang, Zhirui, Park, Jong-Kyu, Menard, Jonathan E., Liu, Yue-Qiang, Kaye, Stanley M., and Gerhardt, Stefan P. Drift kinetic effects on the plasma response in high beta spherical tokamak experiments. United States: N. p., 2017. Web. doi:10.1088/1741-4326/aa8e08.
Wang, Zhirui, Park, Jong-Kyu, Menard, Jonathan E., Liu, Yue-Qiang, Kaye, Stanley M., & Gerhardt, Stefan P. Drift kinetic effects on the plasma response in high beta spherical tokamak experiments. United States. doi:10.1088/1741-4326/aa8e08.
Wang, Zhirui, Park, Jong-Kyu, Menard, Jonathan E., Liu, Yue-Qiang, Kaye, Stanley M., and Gerhardt, Stefan P. 2017. "Drift kinetic effects on the plasma response in high beta spherical tokamak experiments". United States. doi:10.1088/1741-4326/aa8e08. https://www.osti.gov/servlets/purl/1395003.
@article{osti_1395003,
title = {Drift kinetic effects on the plasma response in high beta spherical tokamak experiments},
author = {Wang, Zhirui and Park, Jong-Kyu and Menard, Jonathan E. and Liu, Yue-Qiang and Kaye, Stanley M. and Gerhardt, Stefan P.},
abstractNote = {The high β plasma response to rotating n = 1 external magnetic perturbations is numerically studied and compared with the National Spherical Torus Experiment (NSTX). The hybrid magnetohydrodynamic(MHD)-kinetic modeling shows that drift kinetic effects are important in resolving the disagreement of plasma response between the ideal MHD prediction and the NSTX experimental observation when plasma pressure reaches and exceeds the no-wall limit. Since the external rotating fields and high plasma rotation are presented in the NSTX experiments, the importance of the resistive wall effect and plasma rotation in determining the plasma response is also identified, where the resistive wall suppresses the plasma response through the wall eddy current. The inertial energy due to plasma rotation destabilizes the plasma. In conclusion, the complexity of the plasma response in this study indicates that MHD modeling, including comprehensive physics, e.g. the drift kinetic effects, resistive wall and plasma rotation, are essential in order to reliably predict the plasma behavior in a high beta spherical tokamak device.},
doi = {10.1088/1741-4326/aa8e08},
journal = {Nuclear Fusion},
number = 1,
volume = 58,
place = {United States},
year = 2017,
month = 9
}

Journal Article:
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