Thermal-hydraulic aspects of FCIs in TROI corium/water interaction tests

This paper aims to clarify the thermal-hydraulic effect on the results of TROI corium/water interaction tests. The comparisons were done within the same material melt of 70:30 corium to exclude the material effect. Thermal-hydraulic aspects of corium/water tests are similar to past melt/water tests. The spontaneous steam explosion is a stochastic phenomenon. The depth has a negative effect on a spontaneous steam explosion, while the water pool area and water subcooling have a positive effect on a spontaneous steam explosion. The external triggering event always creates a steam explosion, eliminating the negative thermal-hydraulic effects to prevent such an explosion. The deep and narrow water pool effect, however, works on corium-water tests even with the external triggering event, and deters a triggered steam explosion.