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

[3L12] Core characteristics of sodium cooled RFBB with Metal Fuel

*Naoki Horiike¹, Toru Obara¹ (1. Tokyo Tech)

Keywords:RFBB, Breed-and-Burn Fast Reactor, Metal Fuels, Sodium Coolant, Start-up Core

Previous research on metal-fueled RFBB cores has focused on achieving criticality in the equilibrium state and shuffling methods. However, there are few studies that discuss the start-up phase of the reactor. The purpose of this study is to analyze the start-up core of RFBB and to clarify the effect of core swelling on burnup characteristics. To design a start-up core, plutonium fuels whose infinite multiplication factor were the same as those in the equilibrium state were used. The results of the analysis show criticality was achieved from the initial step. It was found the excess reactivity could be suppressed by adjusting the shuffling interval. The effect of core swelling on the effective multiplication factor was clarified for the start-up core.