On Modelling of Beryllium Molten Depths in Simulated Plasma Disruptions

Plasma facing components in tokamak type fusion reactors are subjected to intense heat load during plasma disruptions. the influence of high heat fluxes on the depth of heat affected zones on pure beryllium metal and beryllium containing very low levels of surface active impurities, has been studied by using a 2-D transient computer model which solves the equations of motion and energy. Results are presented for a range of energy densities and disruption times. It is demonstrated that under certain conditions, impurities through their effect on surface tension create convective flows, hence exercising an influence on the flow intensities and resulting depths of beryllium molten layers during plasma disruptions. The calculated depths of molten layers are also compared with other mathematical models that habe neen based on the assumption that heat is transported through the material by conduction only.JRC.(IAM)-Institute For Advanced Material