Experiment study on the flow mechanism of the molten pool relocation using simulant materials at room temperature

The relocation mechanisms of molten core have an important effect on the core degradation process which is a complicated coupled process of oxidation, flow, and heat transfer with great uncertainty. However, most relocation experiments are complicated integral-effects bundle experiments, too many factors are involved, and it is difficult to obtain the flow resistance correlation for the molten pool flow in the bundle channel. So in this paper, a separate-effects visualization experiment study on the flow mechanism of the molten pool relocation was conducted by using glycerol-water solutions at room temperature with a 2 × 2 bundle channel. The flow front of glycerol-water solutions can be captured by the high-speed camera via a transparent plexiglass shroud. And a new flow resistance correlation of the bundle channel for the molten pool relocation is obtained. In addition, the influence of flowing gas on the relocation process of the molten pool is also investigated. This study is supposed to provide valuable references for the calculation model of the molten pool relocation in severe accident analysis codes.