Experimental study on coolability of particulate core-metal debris bed with oxidization, (I) fragmentation and enhanced heat transfer in zircaloy-50wt%Ag debris bed

The coolability of particulate Zircaloy-50wt%Ag debris bed was investigated under a wet condition with a thin water layer. It was observed that the particulate Zircaloy-50wt%Ag debris bed is finely fragmented by oxidization in a short time period, resulting in a high-coolability debris bed because of the high capillary force of the small particulates produced. It was shown that the fine particles were deposited in the lower layer of the debris bed close to and/or in the water layer. It was also shown that the downward surface of the cylindrical block decreases from an initial temperature of 1000°C to well below 500°C because of the high capillary force in a fine particulate debris bed.