Effects of magnetic drift tangential to magnetic surfaces on neoclassical transport in nonaxisymmetric plasmas
Abstract
In evaluating neoclassical transport by radially local simulations, the magnetic drift tangential to a flux surface is usually ignored in order to keep the phasespace volume conservation. In this paper, effect of the tangential magnetic drift on the local neoclassical transport is investigated. To retain the effect of the tangential magnetic drift in the local treatment of neoclassical transport, a new local formulation for the drift kinetic simulation is developed. The compressibility of the phasespace volume caused by the tangential magnetic drift is regarded as a source term for the drift kinetic equation, which is solved by using a twoweight δf Monte Carlo method for nonHamiltonian system [G. Hu and J. A. Krommes, Phys. Plasmas 1, 863 (1994)]. It is demonstrated that the effect of the drift is negligible for the neoclassical transport in tokamaks. In nonaxisymmetric systems, however, the tangential magnetic drift substantially changes the dependence of the neoclassical transport on the radial electric field E{sub r}. The peaked behavior of the neoclassical radial fluxes around E{sub r }={sub }0 observed in conventional local neoclassical transport simulations is removed by taking the tangential magnetic drift into account.
 Authors:
 Research Organization for Information Science and Technology, 6F KimecCenter Build., 152 Minatojimaminamimachi, Chuoku, Kobe 6500047 (Japan)
 National Institute for Fusion Science, 3226 Oroshicho, Toki 5095292 (Japan)
 (The Graduate University for Advanced Studies), 3226 Oroshicho, Toki 5095292 (Japan)
 Publication Date:
 OSTI Identifier:
 22490972
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 7; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AXIAL SYMMETRY; COMPRESSIBILITY; ELECTRIC FIELDS; HAMILTONIANS; KINETIC EQUATIONS; MAGNETIC SURFACES; MONTE CARLO METHOD; NEOCLASSICAL TRANSPORT THEORY; PHASE SPACE; TOKAMAK DEVICES
Citation Formats
Matsuoka, Seikichi, Email: matsuoka@rist.or.jp, Satake, Shinsuke, Kanno, Ryutaro, Department of Fusion Science, SOKENDAI, and Sugama, Hideo. Effects of magnetic drift tangential to magnetic surfaces on neoclassical transport in nonaxisymmetric plasmas. United States: N. p., 2015.
Web. doi:10.1063/1.4923434.
Matsuoka, Seikichi, Email: matsuoka@rist.or.jp, Satake, Shinsuke, Kanno, Ryutaro, Department of Fusion Science, SOKENDAI, & Sugama, Hideo. Effects of magnetic drift tangential to magnetic surfaces on neoclassical transport in nonaxisymmetric plasmas. United States. doi:10.1063/1.4923434.
Matsuoka, Seikichi, Email: matsuoka@rist.or.jp, Satake, Shinsuke, Kanno, Ryutaro, Department of Fusion Science, SOKENDAI, and Sugama, Hideo. 2015.
"Effects of magnetic drift tangential to magnetic surfaces on neoclassical transport in nonaxisymmetric plasmas". United States.
doi:10.1063/1.4923434.
@article{osti_22490972,
title = {Effects of magnetic drift tangential to magnetic surfaces on neoclassical transport in nonaxisymmetric plasmas},
author = {Matsuoka, Seikichi, Email: matsuoka@rist.or.jp and Satake, Shinsuke and Kanno, Ryutaro and Department of Fusion Science, SOKENDAI and Sugama, Hideo},
abstractNote = {In evaluating neoclassical transport by radially local simulations, the magnetic drift tangential to a flux surface is usually ignored in order to keep the phasespace volume conservation. In this paper, effect of the tangential magnetic drift on the local neoclassical transport is investigated. To retain the effect of the tangential magnetic drift in the local treatment of neoclassical transport, a new local formulation for the drift kinetic simulation is developed. The compressibility of the phasespace volume caused by the tangential magnetic drift is regarded as a source term for the drift kinetic equation, which is solved by using a twoweight δf Monte Carlo method for nonHamiltonian system [G. Hu and J. A. Krommes, Phys. Plasmas 1, 863 (1994)]. It is demonstrated that the effect of the drift is negligible for the neoclassical transport in tokamaks. In nonaxisymmetric systems, however, the tangential magnetic drift substantially changes the dependence of the neoclassical transport on the radial electric field E{sub r}. The peaked behavior of the neoclassical radial fluxes around E{sub r }={sub }0 observed in conventional local neoclassical transport simulations is removed by taking the tangential magnetic drift into account.},
doi = {10.1063/1.4923434},
journal = {Physics of Plasmas},
number = 7,
volume = 22,
place = {United States},
year = 2015,
month = 7
}

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