Viscous relaxation of drift-Alfven waves in tokamaks and its application for triggering improved confinement regimes

摘要

Viscous damping of the drift-Alfven modes in tokamaks and its application for triggering improved confinement regimes are considered. It is shown that these waves are effectively damped by the neoclassical viscosity with the upper limit for their frequency omega equal to the collision frequency of slow ions nu(i)/epsilon, where epsilon is the inverse aspect ratio. Quasistationary plasma poloidal and toroidal velocities and current drive produced by damping of these waves are estimated. Evaluations of the viscosity effects on the Alfven waves which were induced by the dynamic ergodic divertor in the Tokamak Experiment for Technology Oriented Research tokamak [K. H. Finken , Phys. Rev. Lett. 94, 015003 (2005)] are made. (c) 2007 American Institute of Physics.