MHD SIMULATION OF THE TOROIDAL PHASE LOCKING MECHANISM IN A REVERSED FIELD PINCH PLASMA

The toroidal phase locking process of kink modes in a reversed field pinch (RFP) plasma is investigated in detail by means of magnetohydrodynamic (MHD) simulation. The physical mechanism of phase locking is clarified. The two most dominant linearly unstable kink modes govern the evolution of other kink modes, whereby phase locking takes place. It is confirmed that the phase locking process is not a special phenomenon of plasmas with a resistive boundary, but a common feature of the MHD relaxation process in RFPs. The relation between the phase locking process and the MHD relaxation process is briefly discussed. It is found that phase locking is reproduced cyclically in the sustainment process.