Unsteady Sensitivity Analysis of Corium Solidification in a Horizontal Pipe Flow

Abstract

In a reactor core meltdown, the molten material (corium) could be ejected through existing vessel penetrations. With an adequate heat sink the corium could solidify and plug the pipes. Simulations of the melt flow in a horizontal tube have been carried out to conduct a sensitivity study on the effect of the melt penetration distance and bulk temperature distribution of the corium. The wall temperature varied from 400 K to 1,400 K, the Reynolds number varied from 10,000 to 20,000, inlet temperature varied from 2,600 K to 3,000 K, the thermal conductivity varied from 10 W/mK to 20 W/mK, and pipe diameter varied from 0.0095 m to 0.019 m. Additionally, a comparison was made with an analytical model based on a modified Epstein’s model for two Nusselt number correlations. The study provides insight into the approximation of predicting the potential penetration length of corium in horizontal pipes.