[1I01-04] Criticality Safety of Fuel Debris

[1I03] Consequence analysis of postulated criticality in SFP using the randomized model of fuel debris

*Irwan Liapto Simanullang¹, Yuichi Yamane¹, Takeo Kikuchi¹, Kotaro Tonoike¹ (1. JAEA)

Keywords:Criticality accident, randomized distribution, fuel debris, Nordheim-Fuchs model, number of fission

A postulated criticality event has been studied that occurred in fuel debris produced after the loss of cooling function in a spent fuel pool (SFP). The 1/f^β spectrum model was applied to deal with the random distribution composition of fuel debris and concrete. The fission numbers were calculated with the randomized model. In this case, 100 replicas were considered to understand the fluctuation of fission numbers. The results showed that the fission numbers per volume varying from 4.05 x 10¹⁸ to 1.6 x 10¹⁹.