2D MHD Simulation of Spherical Tokamak Formation and Merging with Maximized Heating Power

Abstract

We successfully made 2D MHD simulation of spherical tokamak (ST) formation and merging using a cylindrical vacuum vessel model with a pair of external poloidal field (PF) coils. We swing down the PF coil currents, forming merging ST plasmas with both of private and common poloidal fluxes and the merging process transform the former flux to the latter flux through magnetic reconnection. Under the fixed amount of PF coil energy, we optimized PF coil position to maximize the private poloidal magnetic flux which reconnects for the reconnection heating.