[3L11-13] Breed-and Burn Fast Reactor

[3L13] Start-up core characteristics of Lead-cooled RFBB with Nitride Fuel

*Ren Horikoshi¹, Toru Obara¹ (1. Tokyo Tech)

Keywords:Lead-cooled Fast Reactor, Breed-and-Burn Fast Reactor, Start-up Core, RFBB, Nitride Fuel

Start-up core characteristics of Lead-cooled RFBB with Nitride Fuel were analyzed. It is clarified that by the loading of Pu nitride fuel properly, the core can be critical from the start-up to the equilibrium state. It is also found that excess reactivity can be suppressed by adjusting the shuffling interval of the fuels. Besides, the change in the composition of the discharged fuel from the start-up were clarified. In addition, the change in criticality due to swelling of fuel assemblies was analyzed. To clarify the change in criticality, criticality calculations were performed taking into account the volume increase and density decrease of fuel and cladding due to the swelling.