SCK•CEN 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 and was identified as the European Technology Pilot Plant for the Lead-cooled Fast Reactor.

In this paper we will present selected topics from the R&D program on HLM thermal-hydraulics that are essential for the design, engineering and safety analysis of MYRRHA and other HLM-cooled reactors, including turbulent heat transfer in HLM, fuel assembly thermal hydraulics and flow-induced vibrations, control rod hydrodynamics, primary heat exchanger pool and integral system thermal hydraulics, sloshing and multi-physics modelling.