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Title: Resistive MHD modelling of the quasi-single helicity state in the KTX regimes

Abstract

Here, the potential formation of a quasi-single-helicity (QSH) state in the Keda Torus eXperiment (KTX) is investigated in resistive MHD simulations using the NIMROD code. We focus on the effects of finite resistivity on the mode structure and characteristics of the dominant linear and nonlinear resistive tearing-mode in a finite β, cylindrical configuration of a reversed field pinch model for KTX. In the typical resistive regimes of KTX where the Lundquist number $$S=5 \times 10^4$$ , the plasma transitions to a steady QSH state after evolving through an initial transient phase with multiple helicities. The dominant mode of the QSH state develops from the dominant linear tearing mode instability. In the lower β regime, the QSH state is intermittent and short in duration; in the higher β regime, the QSH state persists for a longer time and should be more easily observed in experiments.

Authors:
 [1];  [2];  [1];  [1]
  1. Univ. of Science and Technology of China, Hefei (China)
  2. Univ. of Science and Technology of China, Hefei (China); Univ. of Wisconsin, Madison, WI (United States)
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). National Energy Research Scientific Computing Center (NERSC)
Sponsoring Org.:
USDOE Office of Science (SC)
Contributing Org.:
KTX Team
OSTI Identifier:
1523626
Grant/Contract Number:  
AC02-05CH11231; FC02-08ER54975; FG02-86ER53218
Resource Type:
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

Citation Formats

Luo, Bing, Zhu, Ping, Li, Hong, and Liu, Wandong. Resistive MHD modelling of the quasi-single helicity state in the KTX regimes. United States: N. p., 2017. Web. doi:10.1088/1741-4326/aa9291.
Luo, Bing, Zhu, Ping, Li, Hong, & Liu, Wandong. Resistive MHD modelling of the quasi-single helicity state in the KTX regimes. United States. https://doi.org/10.1088/1741-4326/aa9291
Luo, Bing, Zhu, Ping, Li, Hong, and Liu, Wandong. Thu . "Resistive MHD modelling of the quasi-single helicity state in the KTX regimes". United States. https://doi.org/10.1088/1741-4326/aa9291. https://www.osti.gov/servlets/purl/1523626.
@article{osti_1523626,
title = {Resistive MHD modelling of the quasi-single helicity state in the KTX regimes},
author = {Luo, Bing and Zhu, Ping and Li, Hong and Liu, Wandong},
abstractNote = {Here, the potential formation of a quasi-single-helicity (QSH) state in the Keda Torus eXperiment (KTX) is investigated in resistive MHD simulations using the NIMROD code. We focus on the effects of finite resistivity on the mode structure and characteristics of the dominant linear and nonlinear resistive tearing-mode in a finite β, cylindrical configuration of a reversed field pinch model for KTX. In the typical resistive regimes of KTX where the Lundquist number $S=5 \times 10^4$ , the plasma transitions to a steady QSH state after evolving through an initial transient phase with multiple helicities. The dominant mode of the QSH state develops from the dominant linear tearing mode instability. In the lower β regime, the QSH state is intermittent and short in duration; in the higher β regime, the QSH state persists for a longer time and should be more easily observed in experiments.},
doi = {10.1088/1741-4326/aa9291},
journal = {Nuclear Fusion},
number = 1,
volume = 58,
place = {United States},
year = {Thu Dec 07 00:00:00 EST 2017},
month = {Thu Dec 07 00:00:00 EST 2017}
}

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