Momentum Conservation and Nonlinear RF-Induced Flows

Recent progress on the numerical computation of 2D full-wave field solutions has motivated advances in the nonlinear theory of rf-induced plasma flows for the control of turbulence. Here, an accounting of how momentum is injected into the system by the antenna, and how it can be transferred from waves to plasma flows and to the equilibrium magnetic field coils and walls is given. Equations for both the plasma momentum and the wave momentum are developed. The former is a recapitulation of results from nonlinear flow drive theory. The latter equation yields a generalized form of the Maxwell stress tensor, including plasma dielectric effects. It is shown that momentum is conserved by the plasma-wave-antenna-wall system for poloidal and toroidal flux-surface-averaged flows. In general, however, momentum exchange with the equilibrium magnetic field coils is possible