NSTX High Harmonic Fast Wave Calculations For Development of CD Operations
Abstract
Improvements in the vacuum feedthroughs permitted higher power HHFW current drive experiments to be performed on NSTX in 2003. Up to 4.3 MW was applied to He plasmas, raising the peak central electron temperature up to 2.3 keV. Normalized current drive efficiency estimates (γ ∼ 0.035x10^19 A'W-1m-2) were similar to those previously obtained for D plasmas at lower power (2.1 MW) and Te0 (1.4 keV) for similar conditions (kz = 7.6 m-1, <ne> ∼ 1x10^19 m-3, Ip = 0.5 MA). Studies are being performed with the full-wave code AORSA to determine the optimum launched wave spectrum which will both heat the electrons effectively and drive current efficiently with the present system. These calculations will be compared to results from both ray-tracing codes and other full-wave codes. The RANT3D code will be used to calculate the plasma loading for these phasing scenarios so that power tuning/matching requirements can be anticipated.
- Publication:
-
APS Division of Plasma Physics Meeting Abstracts
- Pub Date:
- October 2003
- Bibcode:
- 2003APS..DPPLP1019R