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Title: Effect of sheared flow on magnetic islands

Abstract

The effect of sheared flow on a magnetic island is examined. In contrast to the density and temperature gradients which are flattened for sufficiently wide islands, it is found that the velocity gradient persists inside the separatrix whenever the constant-{psi} approximation is satisfied. It follows that velocity shear has a negligible effect on island amplitude in that approximation. The effect of the violation of the constant-{psi} approximation is explored by using the Kelvin-Stuart family of islands, and it is found that flattening is modest even when the separatrix encloses virtually all the current.

Authors:
; ;  [1];  [2]
  1. Institute for Fusion Studies, University of Texas, Austin, Texas 78712 (United States)
  2. (Italy)
Publication Date:
OSTI Identifier:
20974825
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 14; Journal Issue: 2; Other Information: DOI: 10.1063/1.2434251; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AMPLITUDES; APPROXIMATIONS; ELECTRON TEMPERATURE; ION TEMPERATURE; MAGNETIC ISLANDS; MAGNETOHYDRODYNAMICS; PLASMA; PLASMA DENSITY; SHEAR; TEMPERATURE GRADIENTS; VELOCITY

Citation Formats

Waelbroeck, F. L., Fitzpatrick, R., Grasso, Daniela, and Burning Plasma Research Group, Department of Energetics, Politecnico di Torino and CNISM, C.so Duca degli Abruzzi 24, 10129 Turin. Effect of sheared flow on magnetic islands. United States: N. p., 2007. Web. doi:10.1063/1.2434251.
Waelbroeck, F. L., Fitzpatrick, R., Grasso, Daniela, & Burning Plasma Research Group, Department of Energetics, Politecnico di Torino and CNISM, C.so Duca degli Abruzzi 24, 10129 Turin. Effect of sheared flow on magnetic islands. United States. doi:10.1063/1.2434251.
Waelbroeck, F. L., Fitzpatrick, R., Grasso, Daniela, and Burning Plasma Research Group, Department of Energetics, Politecnico di Torino and CNISM, C.so Duca degli Abruzzi 24, 10129 Turin. Thu . "Effect of sheared flow on magnetic islands". United States. doi:10.1063/1.2434251.
@article{osti_20974825,
title = {Effect of sheared flow on magnetic islands},
author = {Waelbroeck, F. L. and Fitzpatrick, R. and Grasso, Daniela and Burning Plasma Research Group, Department of Energetics, Politecnico di Torino and CNISM, C.so Duca degli Abruzzi 24, 10129 Turin},
abstractNote = {The effect of sheared flow on a magnetic island is examined. In contrast to the density and temperature gradients which are flattened for sufficiently wide islands, it is found that the velocity gradient persists inside the separatrix whenever the constant-{psi} approximation is satisfied. It follows that velocity shear has a negligible effect on island amplitude in that approximation. The effect of the violation of the constant-{psi} approximation is explored by using the Kelvin-Stuart family of islands, and it is found that flattening is modest even when the separatrix encloses virtually all the current.},
doi = {10.1063/1.2434251},
journal = {Physics of Plasmas},
number = 2,
volume = 14,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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