抄録
In the present study, analyses of accident progression in a spent fuel pool (SFP) were performed using the Modular Accident Analysis Program (MAAP) code to investigate the cooling characteristics of an SFP spray and alternate water injection in loss-of-cooling and loss-of-coolant accidents. A fuel cladding oxidation model created by JAEA on the basis of their experimental data was selected and applied in the present calculations. In the case of an instantaneous loss-of-coolant accident in the SFP involving spent fuels with 4 months of cooling (3.0 kW/FA), when the SFP spray of 12.5 kg/s (200 GPM) starts within 4 h of the onset of an accident and if the fraction of spray entering the fuel assembly is greater than 30%, fuel cladding failure can be prevented. In the case of a loss-ofcooling accident with water leakage of 19.0 kg/s from the SFP involving spent fuels with 4 months of cooling (3.0 kW/FA), when alternate water injection of 31.3 kg/s (500 GPM) starts within 4 h after the water level reaches the top of the active fuel, fuel cladding failure can be prevented.
