A review of recent numerical and experimental research progress on CDA safety analysis of LBE-/lead-cooled fast reactors

Abstract

The LBE- or Lead-cooled Fast Reactor (LFR) is a kind of advanced reactor which is included in the Generation IV nuclear energy systems. The Core Disruptive Accident (CDA), which is also called severe accident, is meaningful for the research and development (R&D) work of LFRs. In this paper, the recent numerical simulation and experimental research progress on accident scenarios and key phenomena in the reactor primary system after CDA happens is reviewed and summarized, aiming at providing a useful reference for the future CDA study and safety assessment of LFRs. In the recent numerical simulation studies, the investigations of fuel dispersion processes were in the majority. The analysis results indicated that the occurrence risks of re-criticality in CDA conditions for different LFR designs were different. The numerical simulation research on molten material freezing behavior mainly served the verification of calculation models of safety analysis codes. The experimental studies on mobility behavior of solid particles and molten material freezing were also mainly used to verify the safety analysis codes. The numerical and experimental studies on fuel and coolant interaction (FCI) in CDAs of LFRs were both very few. Three potential further research aspects are suggested for the future study on CDA safety analysis of LFRs. The numerical simulation on fuel particle dispersion processes in CDAs of new LFR designs is still suggested as the essential study content as it is much more effective and convenient. Further experiments for code verification and phenomenon study in CDAs are also necessary, which could close some research gaps for CDA safety analysis of LFRs.