Molten metal and water direct contact interaction research – I. Photographic experiment study

Abstract In a large-scale vapor explosion, direct contact between the high temperature liquid and cold liquid after the vapor film collapse could induce the fragmentation process, which is one of the important processes in fuel–coolant interaction. The direct contact interaction between molten metal and water is complicated and still not understood sufficiently. In this paper, interaction behaviors of water droplet with molten metal are studied experimentally by releasing water droplet into high temperature molten tin in a thin vessel. The photographs of interaction phenomenon in molten tin environment are obtained by using a high speed camera. Two typical modes are observed, i.e. no interaction mode and explosive interaction mode. The phenomena of these two interaction modes include water droplet behavior, vaporization process at the interface between the molten tin and water, and interaction area expansion are interpreted in detail. For explosive interaction mode, the severity of thermal interaction is reflected by the interaction area expansion speed in the experiments. The effects of tin temperature, water temperature and Weber number on the interaction area expansion are discussed. The results help us to understand thermal interaction mechanism inside metal and obtain parameters influences on severity of thermal interaction.