MAGNETIC ISLAND DYNAMICS UNDER EXTERNAL MAGNETIC PERTURBATION IN ROTATING RESISTIVE ITER PLASMA

Abstract

The modeling of the magnetic island evolution under resonant magnetic perturbations, RMP, in rotating ITER-like plasma from seed island initial generation, through appearance and development of the NTM till its locking and saturation is presented. The effects of plasma resistivity, viscosity, diamagnetic drift and the effect of the currents induced in the resistive vacuum vessel wall are taken into account. The calculations are carried out with the TEAR code based on the non-linear modified Rutherford model. The dependence of the tearing mode stability index on the angular position of the mode with respect to the RMP is taken into account. It results in deviations of the magnetic island rotation velocity from the velocity of the plasma layer in the vicinity of the rational magnetic surface. The magnetic island dynamics under RMP is analyzed for the modes originated at the q = 3/2 and q = 2 magnetic surfaces. The NTM behavior is discussed for cases of the seed island generation by different RMP sources including the coils for mitigation of the edge localized modes, ELMs.