Host: The Japan Society of Mechanical Engineers
Name : The 30th International Conference on Nuclear Engineering (ICONE30)
Date : May 21, 2023 - May 26, 2023
The molten-core-coolant interaction is important in assessing the integrity of a reactor pressure vessel (RPV) and containment building (CB). In case of RPV failure during in-vessel retention (IVR), the breakage of the RPV will most likely occur at the level of the upper metallic layer due to the focusing effect. A possible steam explosion may result from the interaction between the metallic melt and water in the CB. If the metallic melt, composed of steel mixed with metallic species such as zirconium and uranium, undergoes oxidation during the premixing, triggering, and explosion phases, the melt oxidation influences the progress of the steam explosion. In this study, a small-scale experiment was conducted by dropping molten droplets composed of stainless steel mixed with zirconium into a water pool. The oxidation characteristics in water, such as drop oxidation, oxide film thickness, and element mapping of the solidified drops, were evaluated by an oxygen analyzer and Scanning Electron Microscope-Energy Dispersive X-ray Spectrometry (SEM-EDX) to clarify the effect of the metal composition of zirconium and stainless steel.
