Korea Atomic Energy Research Institute (KAERI) has been carrying an experimental research program on the steam explosion named “Test for Real cOrium Interaction with water (TROI)” since 1997. The objective of the program is to investigate whether the corium would lead to an energetic steam explosion and to measure the conversion ratio of the energetic steam explosion. In the first series of tests using several kg of ZrO2 where the melt/water interaction were made in the water pool at 30 ∼ 95 °C, either a quenching or a spontaneous steam explosions was observed. In the second series of tests using the mixture of UO2/ZrO2 performed in a similar manner as that of ZrO2, it also resulted in either a quenching or energetic steam explosion. The morphology of debris and pressure profile clearly indicate the differences in those two phenomena. The process parameters including the dynamic pressure, dynamic impulse, water and melt temperature, static pressure inside the containment chamber were measured.
