Investigation of the effects of transient heat loads on plasma-facing materials in Tokamaks

Abstract

Nuclear fusion devices are constantly under the threat of malfunctions coming from the damages of plasma-facing materials due to being affected by thermal heat loads. The frequent heat loads during some transient events in large-scale Tokamaks have always been a great concern for researchers. In ITER, the heat load of GW/m2 is estimated to impose plasma-facing components during edge localized modes, beside the Tokamak steady state load which is about 20 MW/m2. Moreover, there are also other transient thermal loads occurring due to off-normal operation of ITER such as vertical displacement events or disruptions, at the orders of hundreds of MW/m2 and tens of GW/m2, respectively. These loads are great enough to result in severe damages of plasma-facing materials. In this study, the facture of tungsten material under the heat loads of Tokamaks is simulated and the results are presented.