Next generation safety analysis methods for SFRs, 2; Experimental analyses by SIMMER-III for the integral verification of the COMPASS code on fuel-pin disruption and low-energy disrupted core motion

Yamano, Hidemasa   ; Tobita, Yoshiharu

This paper describes experimental analyses using SIMMER-III, which were precedently carried out for the integral verification of the COMPASS code. Two topics of key phenomena in CDAs were presented in this paper: fuel-pin disruption; and low-energy disrupted core motion. To analyze the fuel-pin disruption behavior, the CABRI-EFM1 and the CABRI-E7 in-pile experiments were selected. The SIMMER-III calculation was in good agreement with the overall fuel-pin disruption and dispersion behavior, which was characterized by a thermal pin-failure mode, observed in the CABRI-EFM1 experiment. A mechanical pin-failure mode observed in the CABRI-E7 experiment was also reasonably simulated. Under a low-energy disrupted core condition, significantly reduced melt penetration length was obtained in the THEFIS out-of-pile experiments. SIMMER-III well simulated the melt freezing and blockage behavior observed in the experiment.