Results on thermal hydraulic experiments in the LBE-cooled scaled pool facility E-scape in support of the MYRRHA design and licensing

SCK•CEN, the Belgian Nuclear Research Centre, is at the forefront of Heavy Liquid Metal (HLM) nuclear technology worldwide with the development of the MYRRHA Accelerator Driven System. MYRRHA is a flexible fast-spectrum pool-type research reactor cooled by Lead Bismuth Eutectic (LBE) and was identified as the European Technology Pilot Plant for the Lead-cooled Fast Reactor. In the support of the design and licensing of MYRRHA, the work described in this paper addresses two main research questions through experimental analysis in the thermal hydraulic reactor scale model ESCAPE: Can the core cooling in the pool-type, HLM-cooled MYRRHA reactor be guaranteed in operating and accidental conditions (including passive decay heat removal)? Which parameters influence the balance between thermal mixing and stratification and the flow distribution in the plena of the reactor? The E-SCAPE (European SCAled Pool Experiment) experimental facility is a thermal hydraulic 1/6-scale model of the primary system of the MYRRHA reactor, with an electrical core simulator, cooled by LBE. It provides experimental feedback to the designers on the natural and forced convection flow patterns. Moreover, it provides valuable experimental data for validation of thermal hydraulic codes for their use with LBE. In this paper, we will present a selection of experimental results on steady-state and transient test cases in E-SCAPE and interpret these to answer the research questions above.