Generation of plasma rotation in a tokamak by ion-cyclotron absorption of fast Alfvén waves

F. W. Perkins, R. B. White, P. T. Bonoli, V. S. Chan
2001 Physics of Plasmas  
A mechanism is proposed and evaluated for driving rotation in tokamak plasmas by minority ion-cyclotron heating, even though this process introduces negligible angular momentum. The mechanism has two elements: First, angular momentum transport is governed by a diffusion equation with a no-slip boundary condition at the separatrix. Second, Monte-Carlo calculations show that ion-cyclotron energized particles will provide a torque density source which has a zero volume integral but separated
more » ... ve and negative regions. With such a source, a solution of the diffusion equation predicts the on-axis rotation frequency Ω to be Ω = (4q max W J * ) (eBR 3 a 2 n e (2π) 2 ) -1 (τ M /τ E ) where |J * | ≈ 5-10 is a nondimensional rotation frequency calculated by the Monte-Carlo ORBIT code. Overall, agreement with experiment is good, when the resonance is on the low-field-side of the magnetic axis. The predicted rotation becomes more counter-current and reverses sign on the high field side for a no-slip boundary. The velocity shear layer position is controllable and of sufficient magnitude to affect microinstabilities. External Distribution
doi:10.1063/1.1362535 fatcat:i3cmz24f2zh3vcjp2uglilw4ry