Diamagnetic thresholds for sawtooth cycling in tokamak plasmas
The cycling dynamics of the internal kink mode, which drives sawtooth oscillations in tokamak plasmas, is studied using the three dimensional, non-linear magnetohydrodynamic (MHD) code XTOR-2F [H. Lütjens and J.-F. Luciani, J. Comput. Phys. 229, 8130 (2010)]. It is found that sawtooth cycling, which is characterized by quiescent ramps and fast crashes in the experiment, can be recovered in two-fluid MHD provided that a criterion of diamagnetic stabilization is fulfilled. The simulation results indicate that diamagnetic effects alone may be sufficient to drive sawteeth with complete magnetic reconnection in high temperature Ohmic plasmas.
Keywords: kink instability ; magnetic reconnection ; plasma magnetohydrodynamics ; plasma oscillations ; plasma simulation ; plasma temperature ; plasma toroidal confinement ; sawtooth instability ; Tokamak devices ; High-Temperature Plasmas ; = 1 Oscillations ; M=1 Reconnection ; Mhd ; Modes ; Disruptions ; Simulations ; Stability ; Dynamics ; Sawteeth
Record created on 2011-10-25, modified on 2016-08-09