Pedestal characterization and stability of small-ELM regimes in NSTX

被引：15

作者：

Sontag, A. C. ^{[1
]}

Canik, J. M. ^{[1
]}

Maingi, R. ^{[1
]}

Manickam, J. ^{[2
]}

Snyder, P. B. ^{[3
]}

Bell, R. E. ^{[2
]}

Gerhardt, S. P. ^{[2
]}

Kubota, S. ^{[4
]}

LeBlanc, B. P. ^{[2
]}

Mueller, D. ^{[2
]}

Osborne, T. H. ^{[3
]}

Tritz, K. L. ^{[5
]}

机构：

[1] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA

[2] Princeton Plasma Phys Lab, Princeton, NJ 08543 USA

[3] Gen Atom Co, San Diego, CA 92186 USA

[4] Univ Calif Los Angeles, Inst Plasma & Fus Res, Los Angeles, CA 90095 USA

[5] Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA

来源：

NUCLEAR FUSION | 2011年 / 51卷 / 10期

关键词：

EDGE-LOCALIZED MODES; DIII-D TOKAMAK; COLLISIONALITY REGIME; H-MODE; OPERATION;

D O I：

10.1088/0029-5515/51/10/103022

中图分类号：

O35 [流体力学]; O53 [等离子体物理学];

学科分类号：

070204 ; 080103 ; 080704 ;

摘要：

NSTX has observed transition to a desirable small-ELM regime (called type-V), in which the stored energy loss per ELM is less than 1%, by stabilizing type-I ELMs. This regime is accessed in a lower single null configuration with increased edge collisionality (nu* > 1). Coincident with the transition to this regime, a low-frequency (< 10 kHz) n = 1 mode is observed at the plasma edge in magnetic and soft x-ray diagnostics, with harmonics up to n = 6 observed in some cases. Low-level density fluctuations associated with this mode are observed using microwave reflectometry, but there is no evidence that the mode is providing sufficient transport to stabilize the type-I ELMs. This mode rotates in the electron diamagnetic direction and has shown a phase inversion on USXR channels, indicating that it is resistive in nature. Discharges with type-V and type-I ELMs are both calculated to be on the peeling unstable side of the peeling-ballooning stability curve, with the type-V case at higher normalized pressure gradient and closer to the ballooning stability boundary.

引用

页数：6

共 9 条

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NUCLEAR FUSION, 2018, 58 (11)
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NUCLEAR FUSION, 2011, 51 (06)
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NUCLEAR FUSION, 2024, 64 (10)
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NUCLEAR MATERIALS AND ENERGY, 2023, 34
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