Effect of nonlinear energy transport on neoclassical tearing mode stability in tokamak plasmas
Abstract
An investigation is made into the effect of the reduction in anomalous perpendicular electron heat transport inside the separatrix of a magnetic island chain associated with a neoclassical tearing mode in a tokamak plasma, due to the flattening of the electron temperature profile in this region, on the overall stability of the mode. The onset of the neoclassical tearing mode is governed by the ratio of the divergences of the parallel and perpendicular electron heat fluxes in the vicinity of the island chain. By increasing the degree of transport reduction, the onset of the mode, as the divergence ratio is gradually increased, can be made more and more abrupt. Eventually, when the degree of transport reduction passes a certain critical value, the onset of the neoclassical tearing mode becomes discontinuous. In other words, when some critical value of the divergence ratio is reached, there is a sudden bifurcation to a branch of neoclassical tearing mode solutions. Moreover, once this bifurcation has been triggered, the divergence ratio must be reduced by a substantial factor to trigger the inverse bifurcation.
- Authors:
-
- Univ. of Texas, Austin, TX (United States). Dept. of Physics, Inst. of Fusion Studies
- Publication Date:
- Research Org.:
- Univ. of Texas, Austin, TX (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC)
- OSTI Identifier:
- 1535309
- Grant/Contract Number:
- FG02-04ER54742
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Physics of Plasmas
- Additional Journal Information:
- Journal Volume: 24; Journal Issue: 5; 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; physics
Citation Formats
Fitzpatrick, Richard. Effect of nonlinear energy transport on neoclassical tearing mode stability in tokamak plasmas. United States: N. p., 2017.
Web. doi:10.1063/1.4982610.
Fitzpatrick, Richard. Effect of nonlinear energy transport on neoclassical tearing mode stability in tokamak plasmas. United States. https://doi.org/10.1063/1.4982610
Fitzpatrick, Richard. Fri .
"Effect of nonlinear energy transport on neoclassical tearing mode stability in tokamak plasmas". United States. https://doi.org/10.1063/1.4982610. https://www.osti.gov/servlets/purl/1535309.
@article{osti_1535309,
title = {Effect of nonlinear energy transport on neoclassical tearing mode stability in tokamak plasmas},
author = {Fitzpatrick, Richard},
abstractNote = {An investigation is made into the effect of the reduction in anomalous perpendicular electron heat transport inside the separatrix of a magnetic island chain associated with a neoclassical tearing mode in a tokamak plasma, due to the flattening of the electron temperature profile in this region, on the overall stability of the mode. The onset of the neoclassical tearing mode is governed by the ratio of the divergences of the parallel and perpendicular electron heat fluxes in the vicinity of the island chain. By increasing the degree of transport reduction, the onset of the mode, as the divergence ratio is gradually increased, can be made more and more abrupt. Eventually, when the degree of transport reduction passes a certain critical value, the onset of the neoclassical tearing mode becomes discontinuous. In other words, when some critical value of the divergence ratio is reached, there is a sudden bifurcation to a branch of neoclassical tearing mode solutions. Moreover, once this bifurcation has been triggered, the divergence ratio must be reduced by a substantial factor to trigger the inverse bifurcation.},
doi = {10.1063/1.4982610},
journal = {Physics of Plasmas},
number = 5,
volume = 24,
place = {United States},
year = {Fri Apr 28 00:00:00 EDT 2017},
month = {Fri Apr 28 00:00:00 EDT 2017}
}
Web of Science
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Works referencing / citing this record:
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