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Title: Thermal transport dynamics in the quasi-single helicity state

Abstract

Here, a dynamical model describing oscillations between multiple and single helicity configurations in the quasi-single helicity (QSH) state of the reversed field pinch is extended to include electron temperature profile dynamics. It is shown that QSH dynamics is linked to the electron temperature profile because the suppression of mode coupling between tearing modes proposed to underlie QSH also suppresses magnetic-fluctuation-induced thermal transport. Above the threshold of dominant-mode shear that marks the transition to QSH, the model produces temperature-gradient steepening in the strong shear region. Oscillations of the dominant and secondary mode amplitudes give rise to oscillations of the temperature gradient. The phasing and amplitude of temperature gradient oscillations relative to those of the dominant mode are in agreement with experiment.

Authors:
ORCiD logo [1];  [1]
  1. Univ. of Wisconsin, Madison, WI (United States)
Publication Date:
Research Org.:
Univ. of Wisconsin, Madison, WI (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25); USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)
OSTI Identifier:
1466022
Alternate Identifier(s):
OSTI ID: 1363705
Grant/Contract Number:  
FG02-85ER53212
Resource Type:
Accepted Manuscript
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 24; Journal Issue: 6; Journal ID: ISSN 1070-664X
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Citation Formats

McKinney, I. J., and Terry, P. W. Thermal transport dynamics in the quasi-single helicity state. United States: N. p., 2017. Web. doi:10.1063/1.4985317.
McKinney, I. J., & Terry, P. W. Thermal transport dynamics in the quasi-single helicity state. United States. doi:10.1063/1.4985317.
McKinney, I. J., and Terry, P. W. Tue . "Thermal transport dynamics in the quasi-single helicity state". United States. doi:10.1063/1.4985317. https://www.osti.gov/servlets/purl/1466022.
@article{osti_1466022,
title = {Thermal transport dynamics in the quasi-single helicity state},
author = {McKinney, I. J. and Terry, P. W.},
abstractNote = {Here, a dynamical model describing oscillations between multiple and single helicity configurations in the quasi-single helicity (QSH) state of the reversed field pinch is extended to include electron temperature profile dynamics. It is shown that QSH dynamics is linked to the electron temperature profile because the suppression of mode coupling between tearing modes proposed to underlie QSH also suppresses magnetic-fluctuation-induced thermal transport. Above the threshold of dominant-mode shear that marks the transition to QSH, the model produces temperature-gradient steepening in the strong shear region. Oscillations of the dominant and secondary mode amplitudes give rise to oscillations of the temperature gradient. The phasing and amplitude of temperature gradient oscillations relative to those of the dominant mode are in agreement with experiment.},
doi = {10.1063/1.4985317},
journal = {Physics of Plasmas},
number = 6,
volume = 24,
place = {United States},
year = {2017},
month = {6}
}

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