Fast wave current drive experiment on the DIII-D tokamak
- General Atomics, San Diego, CA (United States)
- Massachusetts Inst. of Tech., Cambridge, MA (United States)
- Oak Ridge National Lab., TN (United States)
- Lawrence Livermore National Lab., CA (United States)
- Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan)
One method of radio-frequency heating which shows theoretical promise for both heating and current drive in tokamak plasmas is the direct absorption by electrons of the fast Alfven wave (FW). Electrons can directly absorb fast waves via electron Landau damping and transit-time magnetic pumping when the resonance condition {omega} {minus} {kappa}{sub {parallel}e}{upsilon}{sup {parallel}e} = O is satisfied. Since the FW accelerates electrons traveling the same toroidal direction as the wave, plasma current can be generated non-inductively by launching FW which propagate in one toroidal direction. Fast wave current drive (FWCD) is considered an attractive means of sustaining the plasma current in reactor-grade tokamaks due to teh potentially high current drive efficiency achievable and excellent penetration of the wave power to the high temperature plasma core. Ongoing experiments on the DIII-D tokamak are aimed at a demonstration of FWCD in the ion cyclotron range of frequencies (ICRF). Using frequencies in the ICRF avoids the possibility of mode conversion between the fast and slow wave branches which characterized early tokamak FWCD experiments in the lower hybrid range of frequencies. Previously on DIII-D, efficient direct electron heating by FW was found using symmetric (non-current drive) antenna phasing. However, high FWCD efficiencies are not expected due to the relatively low electron temperatures (compared to a reactor) in DIII-D.
- Research Organization:
- General Atomics, San Diego, CA (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC03-89ER51114; AC02-78ET51013; AC02-76CH03073; AC05-84OR21400
- OSTI ID:
- 10158586
- Report Number(s):
- GA-A-20930; CONF-920610-6; ON: DE92016253
- Resource Relation:
- Conference: ICPP 92: International conference on plasma physics,Innsbruck (Austria),29 Jun - 3 Jul 1992; Other Information: PBD: Jun 1992
- Country of Publication:
- United States
- Language:
- English
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