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Title: Effects of magnetic drift tangential to magnetic surfaces on neoclassical transport in non-axisymmetric 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 phase-space 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 phase-space volume caused by the tangential magnetic drift is regarded as a source term for the drift kinetic equation, which is solved by using a two-weight δf Monte Carlo method for non-Hamiltonian 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 non-axisymmetric 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:
 [1]; ;  [2];  [3];  [2]
  1. Research Organization for Information Science and Technology, 6F Kimec-Center Build., 1-5-2 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047 (Japan)
  2. National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292 (Japan)
  3. (The Graduate University for Advanced Studies), 322-6 Oroshi-cho, Toki 509-5292 (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, E-mail: 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 non-axisymmetric plasmas. United States: N. p., 2015. Web. doi:10.1063/1.4923434.
Matsuoka, Seikichi, E-mail: 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 non-axisymmetric plasmas. United States. doi:10.1063/1.4923434.
Matsuoka, Seikichi, E-mail: 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 non-axisymmetric plasmas". United States. doi:10.1063/1.4923434.
@article{osti_22490972,
title = {Effects of magnetic drift tangential to magnetic surfaces on neoclassical transport in non-axisymmetric plasmas},
author = {Matsuoka, Seikichi, E-mail: 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 phase-space 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 phase-space volume caused by the tangential magnetic drift is regarded as a source term for the drift kinetic equation, which is solved by using a two-weight δf Monte Carlo method for non-Hamiltonian 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 non-axisymmetric 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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