Numerical studies of radial filament motion in toroidally confined plasmas

Abstract

Numerical studies of radial filament motions in the SOL of toroidally confined plasmas are studies. We use a two dimensional two-field model to characterize blob-like structures in the radial-poloidal domain. These structures are observed to achieve velocities in the order of the ion acoustic velocity in the SOL of tokamaks and other toroidal confinement devices. By numerical means we find a scaling of the radial blob velocity that is inversely proportional to the square of the characteristic blob length. Comparison to an analytic solution show that the analytic solutions overestimates radial blob velocities. We also compare the numerical studies to experimental results and find good agreement.