SIMMER-III analysis of eagle-1 in-pile tests focusing on heat transfer from molten core material to steel-wall structure

Toyooka, Junichi  ; Kamiyama, Kenji  ; Konishi, Kensuke* ; Tobita, Yoshiharu; Sato, Ikken 

In this study, the heat flux from the molten core materials to the outer surface of the inner duct (the pool-to-duct heat flux) was evaluated based on all the EAGLE-1 in-pile experiments available. Through the evaluation, it was understood that the pool-to-duct heat flux was so high in all the in-pile experiments that the duct wall failed without coolant boiling in its behind. It was also indicated that the presence of steel in the molten core mixture played a key role in this high heat flux. Application of the SIMMER-III code for these tests suggested that some model improvements were necessary to simulate pool-to-duct heat transfer behavior in a mechanistic way.