Effect of plasma rotation on sawtooth stabilization by beam ions

doi:https://doi.org/10.2172/757604

Title: Effect of plasma rotation on sawtooth stabilization by beam ions

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Abstract

The sawtooth period in JET ELM-free H-Mode plasmas is increasing with Neutral Beam Injection (NBI) power. For injected power PNBI 12MW no large sawtooth crash is observed during the ELM-free period. However, as the edge stability is improved and external kink modes and ELMs are delayed, a possible sawtooth crash at a high plasma beta becomes a concern. In JET DT experiments, delaying sawteeth was found to be crucial in the quest for high fusion power. Fast particles are known to provide stabilizing effect on sawteeth, however, sawtooth stabilization by NBI ions is not clearly understood, since NBI ions are usually not ''fast'' enough to stabilize the m/n = 1/1 internal kink mode which is believed to cause the crash. In order to understand the observed sawteeth stabilization in tokamak experiments with NBI heating, the internal kink m/n = 1/1 mode stability of JET plasmas was modeled using the NOVA-K code, which is also benchmarked with the nonperturbative version of NOVA and the M3D code. Comparison of m/n = 1/1 mode stabilization by NBI ions in JET and TFTR and application of the nonlinear stabilization criteria is given.

Authors:: Gorelenkov, N N; F Nave, M F; Budny, R; Cheng, C Z; Fu, G Y; Hastie, J; Manickam, J; Park, W

Publication Date:: 2000-06-23

Research Org.:: Princeton Plasma Physics Lab., Princeton, NJ (US)

Sponsoring Org.:: USDOE Office of Energy Research (ER) (US)

OSTI Identifier:: 757604

Report Number(s):: PPPL-3463
TRN: US0003462

DOE Contract Number:: AC02-76CH03073

Resource Type:: Technical Report

Resource Relation:: Other Information: PBD: 23 Jun 2000

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; JET TOKAMAK; SAWTOOTH OSCILLATIONS; STABILIZATION; H-MODE PLASMA CONFINEMENT; D-T OPERATION; KINK INSTABILITY; BEAM INJECTION HEATING; PLASMA SIMULATION; TFTR TOKAMAK

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                    Gorelenkov, N N, F Nave, M F, Budny, R, Cheng, C Z, Fu, G Y, Hastie, J, Manickam, J, and Park, W. Effect of plasma rotation on sawtooth stabilization by beam ions.  United States: N. p., 2000. 
        Web.  doi:10.2172/757604.

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                    Gorelenkov, N N, F Nave, M F, Budny, R, Cheng, C Z, Fu, G Y, Hastie, J, Manickam, J, & Park, W. Effect of plasma rotation on sawtooth stabilization by beam ions.  United States.  https://doi.org/10.2172/757604

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                    Gorelenkov, N N, F Nave, M F, Budny, R, Cheng, C Z, Fu, G Y, Hastie, J, Manickam, J, and Park, W. Fri .  
        "Effect of plasma rotation on sawtooth stabilization by beam ions".  United States.  https://doi.org/10.2172/757604.  https://www.osti.gov/servlets/purl/757604.

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@article{osti_757604,

  title        = {Effect of plasma rotation on sawtooth stabilization by beam ions},

  author       = {Gorelenkov, N N and F Nave, M F and Budny, R and Cheng, C Z and Fu, G Y and Hastie, J and Manickam, J and Park, W},

  abstractNote = {The sawtooth period in JET ELM-free H-Mode plasmas is increasing with Neutral Beam Injection (NBI) power. For injected power PNBI 12MW no large sawtooth crash is observed during the ELM-free period. However, as the edge stability is improved and external kink modes and ELMs are delayed, a possible sawtooth crash at a high plasma beta becomes a concern. In JET DT experiments, delaying sawteeth was found to be crucial in the quest for high fusion power. Fast particles are known to provide stabilizing effect on sawteeth, however, sawtooth stabilization by NBI ions is not clearly understood, since NBI ions are usually not ''fast'' enough to stabilize the m/n = 1/1 internal kink mode which is believed to cause the crash. In order to understand the observed sawteeth stabilization in tokamak experiments with NBI heating, the internal kink m/n = 1/1 mode stability of JET plasmas was modeled using the NOVA-K code, which is also benchmarked with the nonperturbative version of NOVA and the M3D code. Comparison of m/n = 1/1 mode stabilization by NBI ions in JET and TFTR and application of the nonlinear stabilization criteria is given.},

  doi          = {10.2172/757604},

  url          = {https://www.osti.gov/biblio/757604},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {2000},

  month        = {6}

}

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