Corium melt quenching tests at low pressure and subcooled water in FARO Original Research Article

The first two corium melt quenching tests in subcooled water performed in the FAT FCI vessel of the FARO facility are described. The tests, referenced as L-29 and L-31, involved 39 and 92 kg of 80 wt% UO2+20 wt% ZrO2 melt, respectively. The molten material was poured into a 1.5-m depth pool of water at 0.2 MPa and ambient temperature. No spontaneous steam explosion occurred. The quenching process was different between the two tests, producing a conglomerate debris bed in L-29 and a particulate debris bed in L-31, with higher thermal load in L-29 than in L-31. The difference in the melt initial temperature is believed to be the cause of this dissimilarity.