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Title: Parasitic momentum flux in the tokamak core

Abstract

A geometrical correction to the E × B drift causes an outward flux of co-current momentum whenever electrostatic potential energy is transferred to ion parallel flows. The robust, fully nonlinear symmetry breaking follows from the free-energy flow in phase space and does not depend on any assumed linear eigenmode structure. The resulting rotation peaking is counter-current and scales as temperature over plasma current. Lastly, this peaking mechanism can only act when fluctuations are low-frequency enough to excite ion parallel flows, which may explain some recent experimental observations related to rotation reversals.

Authors:
 [1]
  1. Princeton Univ., NJ (United States)
Publication Date:
Research Org.:
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1373094
Alternate Identifier(s):
OSTI ID: 1349366
Grant/Contract Number:
AC02-09CH11466
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 24; Journal Issue: 3; 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; Toroidal plasma confinement; Turbulent flows; Free energy; Energy transfer; Angular momentum

Citation Formats

Stoltzfus-Dueck, T. Parasitic momentum flux in the tokamak core. United States: N. p., 2017. Web. doi:10.1063/1.4977458.
Stoltzfus-Dueck, T. Parasitic momentum flux in the tokamak core. United States. doi:10.1063/1.4977458.
Stoltzfus-Dueck, T. Mon . "Parasitic momentum flux in the tokamak core". United States. doi:10.1063/1.4977458. https://www.osti.gov/servlets/purl/1373094.
@article{osti_1373094,
title = {Parasitic momentum flux in the tokamak core},
author = {Stoltzfus-Dueck, T.},
abstractNote = {A geometrical correction to the E × B drift causes an outward flux of co-current momentum whenever electrostatic potential energy is transferred to ion parallel flows. The robust, fully nonlinear symmetry breaking follows from the free-energy flow in phase space and does not depend on any assumed linear eigenmode structure. The resulting rotation peaking is counter-current and scales as temperature over plasma current. Lastly, this peaking mechanism can only act when fluctuations are low-frequency enough to excite ion parallel flows, which may explain some recent experimental observations related to rotation reversals.},
doi = {10.1063/1.4977458},
journal = {Physics of Plasmas},
number = 3,
volume = 24,
place = {United States},
year = {Mon Mar 06 00:00:00 EST 2017},
month = {Mon Mar 06 00:00:00 EST 2017}
}

Journal Article:
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