3-D MHD simulations of pellet injection and disruptions in tokamak plasmas

Non-linear MHD simulation results of pellet injection show that MHD forces can accelerate large pellets injected on the high field side of a tokamak t o the plasma centre. Magnetic reconnection can produce a reverse shear q pr ofile. Ballooning instability caused by pellets is also reduced by high fie ld side injection. Studies are also reported of the current quench phase of disruptions, which can cause 3-D halo currents and runaway electrons.