A Steam Explosion Experiment with Partially Oxidized Corium in the TROI Facility

A steam explosion experiment (TROI-51) was performed in the TROI facility by using partially oxidized molten corium (core material) which is produced during a postulated core melt accident in a nuclear reactor. Since the prototypic molten core material is composed of fuel (UO2), oxidized cladding material (ZrO2), unoxidized cladding material (Zr metal) and structural material (stainless steel . SS), it extracts uranium metal through a chemical reaction, which could enhance the explosivity of corium because of a burning of the hydrogen generated from the uranium-water interaction. Therefore, it is necessary to perform steam explosion experiments using partially oxidized corium to find the explosivity of the prototypic corium. A triggered steam explosion occurred in this test. The dynamic pressure and the dynamic load measured in this experiment show a stronger explosion that those performed previously with oxidic corium