ELM-free and inter-ELM divertor heat flux broadening induced by edge harmonics oscillation in NSTX
- Univ. of Tennessee, Knoxville, TN (United States)
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
- General Atomics, San Diego, CA (United States)
A new n =1 dominated edge harmonic oscillation (EHO) has been found in NSTX. The new EHO, rotating toroidally in the counter-current direction and the opposite direction of the neutral beam, was observed during certain inter-ELM and ELM-free periods of H-mode operation. This EHO is associated with a significant broadening of the integral heat flux width ($${{\lambda}_{\operatorname{int}}}$$ ) by up to 150%, and a decrease in the divertor peak heat flux by >60%. An EHO induced filament was also observed by the gas puff imaging diagnostic. The toroidal rotating filaments could change the edge magnetic topology resulting in toroidal rotating strike point splitting and heat flux broadening. Finally, experimental result of the counter current rotation of strike points splitting is consistent with the counter-current EHO.
- Research Organization:
- Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)
- Sponsoring Organization:
- USDOE
- Grant/Contract Number:
- AC02-09CH11466; AC05-00OR22725; SC0008309
- OSTI ID:
- 1432665
- Alternate ID(s):
- OSTI ID: 1883012
- Journal Information:
- Nuclear Fusion, Journal Name: Nuclear Fusion Journal Issue: 12 Vol. 57; ISSN 0029-5515
- Publisher:
- IOP ScienceCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Impact of edge harmonic oscillations on the divertor heat flux in NSTX