Development of solidification and segregation model for molten corium

Sato, Takumi ; Oikawa, Katsunari*; Ueshima, Nobufumi*; Nagae, Yuji ; Kurata, Masaki 

Macroscopic segregation of molten core components occurs with slow cooling rate in the accident of Fukushima Daiichi Nuclear Power Plants. In order to investigate these segregation behavior, the solidification model for numerical simulation has been developed. In this model, solidification and microscopic segregation of molten corium are simulated with the Scheil model and thermal properties calculated by Thermo-calc. In this study, the validation of macrosegregation analysis of this model were performed. As the preliminary analysis, the calculation results were compared with corium solidification experiments. It was proved that this model can estimate the tendencies of macrosegregation.