Time: 2012-11-30 14:00:00
Speaker: Wei Shen [IFTS]
Place: Rm. 413, Bld. 11#, Yuquan Campus
Abstract: Title:M3D Simulations of Sawteeth and Snakes in Tokamaks
Abstract:Nonlinear simulations of Sawteeth and Snakes are carried out using M3D. MHD simulations show repeated sawtooth cycles due to a resistive (1,1) internal kink mode for a model tokamak equilibrium with a broader pressure profile. However, sawteeth do not occur for a peaked pressure profile. In this case, a steady state which behaves like a snake follows the initial sawtooth crash. Also we consider the effects of resistivity profile and perpendicular thermal conductivity on the snake. When perpendicular thermal conductivity becomes smaller, the pressure profile is flattened inside and the steady state does not look like snake any more. When the resisitivity changes to constant profile, the steady state changes back to regular sawteeth.