Efficient Generation of Non-Inductive, Off-axis, Ohkawa Current, Driven by Electron Bernstein Waves in High Beta, Spherical Torus Plasmas

Taylor, G. ; Efthimion, P.C. ; Kessel, C.E. ; Harvey, R.W. ; Smirnov, A.P. ; Ershov, N.M. ; Carter, M.D. ; Forest, C.B.

Princeton University. Plasma Physics Laboratory.

关键词: Wave Interaction, Plasma;    Trapped Electrons Current Drive;    70 Plasma Physics And Fusion Technology;    Spherical Torus;    Simulation;   

DOI  :  10.2172/827839
RP-ID  :  PPPL-3943
RP-ID  :  AC02-76CH03073
RP-ID  :  827839

美国|英语

来源: UNT Digital Library

【 摘 要 】

Off-axis rf-driven current can play a critical role in sustaining high Beta spherical torus (ST) plasmas without a central solenoid. Numerical modeling of electron Bernstein wave current drive (EBWCD) for a {Beta} {approx} 40% ST plasma predicts efficient, off-axis, Ohkawa EBWCD. Current can be efficiently driven at r/a greater than 0.5 where the large trapped electron fraction precludes conventional Fisch-Boozer current drive and provides near-ideal conditions for Ohkawa EBWCD. Also, Ohkawa EBWCD efficiency increases with r/a. Enhancement over Fisch-Boozer current drive is a factor of two at r/a {approx} 0.2 rising to over an order of magnitude at r/a {approx} 0.5.