Study on Selection of Internal Initiating Events of Small Natural Circulation Lead-Cooled Fast Reactor

Abstract

The initiating events, as the starting point and basis for the deterministic safety analysis and probabilistic safety assessment of the lead-cooled fast reactor (LFR), provide important guidance on the design optimization and safe operation of reactors. This paper, based on the current design scheme of the small natural circulation lead-cooled fast reactor SNCLFR-100 and by reference to the experience of selecting initiating events of other advanced fast reactors, with the generalized “core melting” taken as the top target event, provides the internal initiating events of SNCLFR-100 by deduction in the master logic diagram (MLD) method, which form a relatively complete list of internal initiating events. This study thus can provide a theoretical basis for the safety analysis of natural circulation LFRs.