Experiments with injection of thermite melt into sodium

The dominating physical phenomena of an interaction between molten core material and sodium are being investigated experimentally. In this experiment the molten core material is simulated by a thermite melt with temperatures up to about 3000deg C. The melt is injected as a jet from below into a sodium pool using a gas pressurized injector system. To observe the course of the interaction of the melt with the coolant X-ray facilities, thermocouples, void detectors, pressure transducers, and a level indicator are used. In the first experiment 5.5 kg melt with a temperature of about 2800deg C were injected within 170 ms into sodium at 500deg C. The paper presents the results of this experiment. (orig.)