Drift Mode Calculations in Nonaxisymmetric Geometry
Abstract
A fully kinetic assessment of the stability properties of toroidal drift modes has been obtained for nonaxisymmetric (stellarator) geometry, in the electrostatic limit. This calculation is a comprehensive solution of the linearized gyrokinetic equation, using the lowestorder ''ballooning representation'' for high toroidal mode number instabilities, with a model collision operator. Results for toroidal drift waves destabilized by temperature gradients and/or trapped particle dynamics are presented, using threedimensional magnetohydrodynamic equilibria generated as part of a design effort for a quasiaxisymmetric stellarator. Comparisons of these results with those obtained for typical tokamak cases indicate that the basic trends are similar.
 Authors:
 Publication Date:
 Research Org.:
 Princeton Plasma Physics Lab., NJ (US)
 Sponsoring Org.:
 USDOE Office of Energy Research (ER) (US)
 OSTI Identifier:
 9115
 Report Number(s):
 PPPL3354; DEAC0276CHO3073
DEAC0276CHO3073; TRN: US0102749
 DOE Contract Number:
 AC0276CH03073
 Resource Type:
 Technical Report
 Resource Relation:
 Other Information: PBD: 1 Jul 1999
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; STELLARATORS; DRIFT INSTABILITY; DESIGN; ELECTROSTATICS; GEOMETRY; KINETICS; MAGNETOHYDRODYNAMICS; THREEDIMENSIONAL CALCULATIONS
Citation Formats
G. Rewoldt, L.P. Ku, W.A. Cooper, and W.M. Tang. Drift Mode Calculations in Nonaxisymmetric Geometry. United States: N. p., 1999.
Web. doi:10.2172/9115.
G. Rewoldt, L.P. Ku, W.A. Cooper, & W.M. Tang. Drift Mode Calculations in Nonaxisymmetric Geometry. United States. doi:10.2172/9115.
G. Rewoldt, L.P. Ku, W.A. Cooper, and W.M. Tang. 1999.
"Drift Mode Calculations in Nonaxisymmetric Geometry". United States.
doi:10.2172/9115. https://www.osti.gov/servlets/purl/9115.
@article{osti_9115,
title = {Drift Mode Calculations in Nonaxisymmetric Geometry},
author = {G. Rewoldt and L.P. Ku and W.A. Cooper and W.M. Tang},
abstractNote = {A fully kinetic assessment of the stability properties of toroidal drift modes has been obtained for nonaxisymmetric (stellarator) geometry, in the electrostatic limit. This calculation is a comprehensive solution of the linearized gyrokinetic equation, using the lowestorder ''ballooning representation'' for high toroidal mode number instabilities, with a model collision operator. Results for toroidal drift waves destabilized by temperature gradients and/or trapped particle dynamics are presented, using threedimensional magnetohydrodynamic equilibria generated as part of a design effort for a quasiaxisymmetric stellarator. Comparisons of these results with those obtained for typical tokamak cases indicate that the basic trends are similar.},
doi = {10.2172/9115},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1999,
month = 7
}

A fully kinetic assessment of the stability properties of toroidal drift modes has been obtained for nonaxisymmetric (stellarator) geometry, in the electrostatic limit. This calculation is a comprehensive solution of the linearized gyrokinetic equation, using the lowestorder {open_quotes}ballooning representation{close_quotes} for high toroidal mode number instabilities, with a model collision operator. Results for toroidal drift waves destabilized by temperature gradients and/or trapped particle dynamics are presented, using threedimensional magnetohydrodynamic equilibria generated as part of a design effort for a quasiaxisymmetric stellarator. Comparisons of these results with those obtained for typical tokamak cases indicate that the basic trends are similar. {copyright} {italmore »

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A fully kinetic assessment of the stability properties of toroidal drift modes has been obtained for a case for the Large Helical Device (LHD) [A.Iiyoshi, et al., Plasma Physics and Controlled Nuclear Fusion Research, 1998, Nucl.Fusion 39, 1245 (1999)]. This calculation retains the important effects in the linearized gyrokinetic equation, using the lowestorder ''ballooning representation'' for high toroidal mode number instabilities in the electrostatic limit. Results for toroidal drift waves destabilized by trapped particle dynamics and ion temperature gradients are presented, using threedimensional magnetohydrodynamics equilibria reconstructed from experimental measurements. The effects of helicallytrapped particles and helical curvature are investigated. 
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