Investigation of the Evolution of Be, Ni, Mo, and W Dust Grains in Fusion Plasma

Abstract

In this work, evolution of dust grains from different materials used in fusion energy installations was studied and a model was constructed that describes the generation of dust. The model accounts for the thermochemical, electrical, and other properties of the materials of the fusion reactor wall. It was shown that the dominant process that leads to the decrease in dust grain mass is the thermal evaporation, which is determined by the saturated vapor pressure at thermal equilibrium temperature. Estimates of the lifetime of dust grains from different materials were obtained depending on plasma parameters. The findings of this work can be useful for estimates of the length of penetration of dust grains into the reactor. The difference in the dynamics of particles from light and heavy elements was shown. Out of the four elements under study (Be, Ni, Mo, and W), nickel grains demonstrate the highest penetrating ability due to their long lifetime and moderate weight.