Extreme Conditions for Plasma-Facing Components in Tokamak Fusion Devices

Abstract

Safe and reliable operation is still one of the major challenges in the development of fusion energy. In magnetic fusion devices, perfect plasma confinement is difficult to achieve. During transient loss of plasma confinement, high plasma power and particle beams (power densities up to hundreds of gigawatts per square meter in time duration on the order of milliseconds) strike the reactor walls, particularly the divertor plate, and can significantly damage the exposed surfaces and also indirectly damage nearby components. To predict the resulting damage of the direct plasma impact on the divertor plate, comprehensive multiphysics multiphase models are developed, integrated, and implemented in the High Energy Interaction with General Heterogeneous Target Systems computer simulation package. The evolution of the divertor material, resulting vaporization, heating and ionization of vapor plasma to higher temperatures, and, consequently, the resulting photon radiation, transport, and deposition around the divertor area are calculated for typical instability parameters of the edge-localized modes and disruption for an ITER-like geometry.