Over 300 small-scale experiments have been performed to investigate the interaction that sometimes occurs when hot liquid metal is poured into a container of water. IN these experiments molten tin was used. The violence of each interaction was classified by measuring the ratio of the mass of comminuted tin to the original mass of tin, and the effect of varying the initial tin and water temperatures. Tf and Tc respectively, was investigated. In Tf-Tc space there exists a zone, the temperature interaction zone (TIZ), outside of which interactions do not occur without external triggering. The time between the tin entering the water, and the start of the interaction was also measured as a function of Tf and Tc.

A model for fuel-coolant interactions is proposed. The interaction is divided into five stages: an initial perturbation which triggers the interaction and causes a vapour bubble to form at the fuel-coolant interface; bubble expansion and collapse with jetting; penetration of the fuel by the liquid jet; heat transfer from the fuel to the jet; the formation of a new bubble. The process repeats itself cyclically from the second stage. The most important result is that the strength of the interaction is reduced as the external pressure is increased and can be inhibited entirely if the pressure is large enough.

No abstract