Investigation of water injection on molten Zirconium-Stainless steel pool in IVR strategy

Abstract Water injection on the surface of the molten pool could enhance the effectiveness of In-Vessel Retention (IVR) strategy and mitigate the thermal load on the vessel wall. The wATer injectiOn on molten Zirconium-Stainless steel Metallic pool experiment (ATOM) has been established to investigate the effect of water injection on the molten pool for IVR strategy. The mass percentage of Zr is 59.5% for the simulant. The mass flow rate of the water injection is 0.10 kg/s, and the maximum heat flux removed by water is 1.18 MW/m2. The experimental results indicate that water injection on the surface of the light metallic layer can significantly reduce the heat flux transferred to the sidewall and mitigate the thermal focusing effect on the Reactor Pressure Vessel (RPV). Hydrogen is produced during the water injection. Neither the vapor explosion nor the melt ejection is found during the whole experiment.