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 nowall 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:
 Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
 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):
 PPPL5442
Journal ID: ISSN 00295515
 Grant/Contract Number:
 AC0209CH11466
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Nuclear Fusion
 Additional Journal Information:
 Journal Volume: 58; Journal Issue: 1; Journal ID: ISSN 00295515
 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, JongKyu, Menard, Jonathan E., Liu, YueQiang, 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:10.1088/17414326/aa8e08.
Wang, Zhirui, Park, JongKyu, Menard, Jonathan E., Liu, YueQiang, Kaye, Stanley M., & Gerhardt, Stefan P. Drift kinetic effects on the plasma response in high beta spherical tokamak experiments. United States. doi:10.1088/17414326/aa8e08.
Wang, Zhirui, Park, JongKyu, Menard, Jonathan E., Liu, YueQiang, Kaye, Stanley M., and Gerhardt, Stefan P. 2017.
"Drift kinetic effects on the plasma response in high beta spherical tokamak experiments". United States.
doi:10.1088/17414326/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, JongKyu and Menard, Jonathan E. and Liu, YueQiang 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 nowall 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 = {10.1088/17414326/aa8e08},
journal = {Nuclear Fusion},
number = 1,
volume = 58,
place = {United States},
year = 2017,
month = 9
}

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