Cyclic medium heat flux testing of a WTa lattice structure on the HIVE facility

Abstract

Testing fusion components in high-heat flux conditions is key for assessing the performance of plasma facing components. A novel limiter mock-up design was tested under cyclic thermal loading in the “Heating by Induction to Verify Extremes” (HIVE) facility at UKAEA. The results demonstrated both the capability of the HIVE facility for cyclic thermal loading and the performance of the mock-up limiter.The mock-up comprised a Tungsten-Tantalum additively manufactured lattice brazed to a copper heatsink. Heat fluxes up to 10 MW/m2 were achieved in the testing and a total of 507 pulses were performed with measured heat fluxes of 8 MW/m2 or higher. HIVE diagnostics (IR camera and thermocouples mounted in the sample) found no measurable change in the steady state thermal behaviour of the mock-up. Visual inspection of the sample after testing revealed cracking had occurred in the lattice structure. IR data also revealed that the cracked region of the lattice had a longer cool-down period to the rest of the structure.Preliminary EM analysis to estimate the variation of heat load between a lattice and a solid block was conducted. To gain confidence in such analysis, more computational time as well as thermal and electrical material properties of AM W at temperature are required.