The residual zonal flow in tokamak plasmas rotating toroidally at sonic speed

摘要

The residual zonal flow, initially driven by ion-temperature-gradient turbulence, is investigated for a tokamak plasma rotating in the toroidal direction at sonic speed. The general expression of the residual zonal flow is the same as that of the static case but the numerical result is different due to the difference in the evaluation of the particle orbit average, the fraction of trapped particles and the non-uniformity of density on magnetic surfaces. For rotations at sonic speed, the value of residual zonal flows is approximately one third of that for static cases. The result is important in the fluid simulation of turbulence for rotating tokamak plasmas.