Theoretical Studies in Tokamak: Task 1, Nonlinear Effects of ICRF Power on Drift Wave Stability and Transport in Tokamaks: Annual Progress Report.

摘要

This report summarizes progress on Task 1 of Contract No. DE-AC03- 88ER53270 for the period April 15, 1988 thru April 14, 1989. During this time, major progress was made in the theoretical understanding of nonlinear interactions of waves in the ion cyclotron range of frequencies (ICRF) with ion temperature gradient-driven drift modes (/eta//sub i/ /minus/ modes) in tokamaks. A dispersion relation was derived for toroidal /eta//sub i/ /minus/ modes nonlinearly modified by sideband interactions caused by a power source in the ICRF. Solutions of the dispersion relation show that /eta//sub i/ /minus/ mode stability can be significantly affected by moderate ICRF power in low density and temperature operating regimes of experimental tokamaks such as PLT, or in the outer (edge) regions of more advanced tokamaks. Stability characteristics in these regimes are strongly modified using short wavelength ion Bernstein waves with k sub 0 > k, k sub 0 /rho//sub i/ > 1, k/sub 0z/v/sub i/ < omega sub 0 < k/sub 0z/v/sub e/, omega sub 0 approx. = omega /sub ci/. 6 refs. (ERA citation 14:029925)