A simulated plasma disruption experiment using an electron beam as a heat source

An experimental study was made on the behavior of a solid surface subjected to an extremely high heat flux similar to that expected during a plasma disruption. An electron beam was used as the heat source to simulate the high heat flux. The beam was defocused in an attempt to give as much uniform heat flux as possible on the test surface. The 5-mm-diameter test pieces were made of 304 stainless steel, aluminum, and zinc. Heat fluxes from 10 to 110 MW/m2 were applied on the test pieces for durations of 90 to 180 msec. Special attention was paid to the measurement of the surface heat flux on the test surface. Comparison between experimental and analytical results on melt layer thickness and evaporation loss is made. An improved thermal analysis code (DAT-K) was developed for the analysis. Agreement between the experimental and analytical results on melt layer thickness is good. For evaporation loss, experimental and analytical results are in fair agreement. Features of the experiments and analysis that lead to the differences in the results are discussed.