Energetic particle effects on n=1 MHD instabilities in a DIII-D hybrid discharge

Statistics – Computation

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

The δf kinetic-MHD model in the 3-D extended MHD code NIMROD is used to perform a simulation study of energetic particle effects on the n=1 mode in a DIII-D hybrid discharge. The hybrid has low qmin>˜1 at high confinement, and is a candidate operational scenario for burning plasma experiments. However hybrid discharges are limited to moderate βN by the m/n=2/1 instability. Using realistic DIII-D equilibria, the stability of the n=1 mode is computed over a (qmin,βN) space. Unstable modes are driven by energetic particles far into the MHD stable region in this space. The drive is associated with the fishbone mode or BAE mode, depending on qmin. The stability boundary is found near the experimental (qmin,βN), where the unstable mode has a m/n=1/1 component localized near the axis. Experimentally, a m/n=1/1 structure is observed in agreement with the computed mode in key physical respects. At higher qmin and βN a mode with a broad m/n=2/1 structure is unstable. This suggests that the m/n=2/1 mode is triggered by energetic particles in these discharges, as βN is increased. A group of several similar discharges shows strong agreement with this computational explanation of onset.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Energetic particle effects on n=1 MHD instabilities in a DIII-D hybrid discharge does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Energetic particle effects on n=1 MHD instabilities in a DIII-D hybrid discharge, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Energetic particle effects on n=1 MHD instabilities in a DIII-D hybrid discharge will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1371315

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.