Numerical Simulation on Influence of Energetic Particles on Tokamak Sawtooth Modes

In tokamak experiments, high-energy particles are observed to exert significant influence on the sawtooth instability. Therefore, this paper uses the gyrokinetic-magnetofluid hybrid model program M3D-K to study the influence of high-energy particles on sawtooth modes. The simulation results indicate that increase in the ratio of energetic particle pressure to total pressure can destabilize the sawtooth instability; increase in the energetic particles energy and pitch angle of energetic particles can stabilize the sawtooth instability; and decrease in the gradient of energetic particle pressure distribution can stabilize the sawtooth instability. These simulation results may provide reference for controlling sawtooth instabilities during future operation of tokamaks.