Shaping Effects on Non-Ideal Ballooning Mode

SETO, Haruki; YAGI, Masatoshi; AIBA, Nobuyuki; MATSUYAMA, Akinobu; DUDSON, Benjamin D.; XU, Xueqiao

doi:10.1585/pfr.13.3403086

Title: Shaping Effects on Non-Ideal Ballooning Mode

Abstract

The dependence of shaping effects on the growth rate of collisionless and resistive ballooning mode (CBM/RBM) is numerically researched. Furthermore, that of the drift ballooning modes (DCBM/DRBM) is investigated by taking kinetic effects into account. Resistivity scans of linear growth rates of CBM/RBM and DCBM/DRBM in a circular geometry show that both modes have 3 branches in accordance with decreasing resistivity, fast, resistive and collisionless branch. The last two branches are in the edge relevant resistivity regime and are in the scope of this paper. For CBM/RBM, shaping effect on the growth rate becomes weak with increasing resistivity and the growth rate monotonically increases with decrease of the elongation and increase of the triangularity, on the other hand, the opposite tendency appears on the triangularity for DCBM, namely it weakly decreases with increase of the triangularity. This fact indicates that the inverted D-shaped equilibrium can be unstable against DCBM compared with the D-shaped equilibrium.

Authors:

SETO, Haruki ^[1]; YAGI, Masatoshi ^[1]; AIBA, Nobuyuki ^[1]; MATSUYAMA, Akinobu ^[1]; DUDSON, Benjamin D. ^[2]; XU, Xueqiao ^[3]

National Inst. for Quantum and Radiological Science and Technology (QST) (Japan)
Univ. of York (United Kingdom)
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Publication Date:: 2018-07-10

Research Org.:: Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Sponsoring Org.:: USDOE National Nuclear Security Administration (NNSA)

OSTI Identifier:: 1568031

Report Number(s):: LLNL-JRNL-744079
Journal ID: ISSN 1880-6821; 899042; TRN: US2100267

Grant/Contract Number:: AC52-07NA27344

Resource Type:: Accepted Manuscript

Journal Name:: Plasma and Fusion Research

Additional Journal Information:: Journal Volume: 13; Journal Issue: 0; Journal ID: ISSN 1880-6821

Publisher:: Japan Society of Plasma Science and Nuclear Fusion Research

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; resistive ballooning mode; collisionless ballooning mode; plasma shaping; electron drift wave

Citation Formats


                    SETO, Haruki, YAGI, Masatoshi, AIBA, Nobuyuki, MATSUYAMA, Akinobu, DUDSON, Benjamin D., and XU, Xueqiao. Shaping Effects on Non-Ideal Ballooning Mode.  United States: N. p., 2018. 
Web.  doi:10.1585/pfr.13.3403086.

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                    SETO, Haruki, YAGI, Masatoshi, AIBA, Nobuyuki, MATSUYAMA, Akinobu, DUDSON, Benjamin D., & XU, Xueqiao. Shaping Effects on Non-Ideal Ballooning Mode.  United States.  https://doi.org/10.1585/pfr.13.3403086

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                    SETO, Haruki, YAGI, Masatoshi, AIBA, Nobuyuki, MATSUYAMA, Akinobu, DUDSON, Benjamin D., and XU, Xueqiao. Tue .  
"Shaping Effects on Non-Ideal Ballooning Mode".  United States.  https://doi.org/10.1585/pfr.13.3403086.  https://www.osti.gov/servlets/purl/1568031.

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@article{osti_1568031,

  title        = {Shaping Effects on Non-Ideal Ballooning Mode},

  author       = {SETO, Haruki and YAGI, Masatoshi and AIBA, Nobuyuki and MATSUYAMA, Akinobu and DUDSON, Benjamin D. and XU, Xueqiao},

  abstractNote = {The dependence of shaping effects on the growth rate of collisionless and resistive ballooning mode (CBM/RBM) is numerically researched. Furthermore, that of the drift ballooning modes (DCBM/DRBM) is investigated by taking kinetic effects into account. Resistivity scans of linear growth rates of CBM/RBM and DCBM/DRBM in a circular geometry show that both modes have 3 branches in accordance with decreasing resistivity, fast, resistive and collisionless branch. The last two branches are in the edge relevant resistivity regime and are in the scope of this paper. For CBM/RBM, shaping effect on the growth rate becomes weak with increasing resistivity and the growth rate monotonically increases with decrease of the elongation and increase of the triangularity, on the other hand, the opposite tendency appears on the triangularity for DCBM, namely it weakly decreases with increase of the triangularity. This fact indicates that the inverted D-shaped equilibrium can be unstable against DCBM compared with the D-shaped equilibrium.},

  doi          = {10.1585/pfr.13.3403086},

  journal      = {Plasma and Fusion Research},

  number       = 0,

  volume       = 13,

  place        = {United States},

  year         = {2018},

  month        = {7}

}

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Figures / Tables:

Fig. 1: Equilibria with same $s$ and $α$ profiles. (a): inverted D-shaped, (b): elliptic and (c): D-shaped equilibrium, where red dashed lines represent horizontal positions of the magnetic axis and black dashed lines represent those of the center of last closed flux surface (black solid). The relation between the poloidalmore »

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