skip to main content

SciTech ConnectSciTech Connect

Title: Nonlinear hybrid simulation of internal kink with beam ion effects in DIII-D

In DIII-D sawteething plasmas, long-lived (1,1) kink modes are often observed between sawtooth crashes. The saturated kink modes have two distinct frequencies. The mode with higher frequency transits to a fishbone-like mode with sufficient on-axis neutral beam power. In this work, hybrid simulations with the global kinetic-magnetohydrodynamic (MHD) hybrid code M3D-K have been carried out to investigate the linear stability and nonlinear dynamics of the nā€‰=ā€‰1 mode with effects of energetic beam ions for a typical DIII-D discharge where both saturated kink mode and fishbone were observed. Linear simulation results show that the nā€‰=ā€‰1 internal kink mode is unstable in MHD limit. However, with kinetic effects of beam ions, a fishbone-like mode is excited with mode frequency about a few kHz depending on beam pressure profile. The mode frequency is higher at higher beam power and/or narrower radial profile consistent with the experimental observation. Nonlinear simulations have been performed to investigate mode saturation as well as energetic particle transport. The nonlinear MHD simulations show that the unstable kink mode becomes a saturated kink mode after a sawtooth crash. With beam ion effects, the fishbone-like mode can also transit to a saturated kink mode with a small but finite mode frequency.more » These results are consistent with the experimental observation of saturated kink mode between sawtooth crashes.« less
Authors:
;  [1] ; ;  [2] ;  [3] ;  [4]
  1. Department of Physics, Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China)
  2. Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)
  3. General Atomics, San Diego, California 92186-5608 (United States)
  4. School of Physics and Optoelectronic Engineering, Dalian University of Technology, Dalian 116024 (China)
Publication Date:
OSTI Identifier:
22408318
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 4; 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; COMPUTERIZED SIMULATION; DOUBLET-3 DEVICE; ION BEAMS; KHZ RANGE; MAGNETOHYDRODYNAMICS; NEUTRAL-PARTICLE TRANSPORT; NONLINEAR PROBLEMS; PLASMA; SAWTOOTH OSCILLATIONS