Evaluation on coolability of the reactor core in Monju by natural circulation under earthquake and subsequent tsunami event

Yamada, Fumiaki; Fukano, Yoshitaka  ; Nishi, Hiroshi; Konomura, Mamoru

The core cooling capability by natural circulations at a station black-out event, induced by an earthquake and a subsequent tsunami attack, has been evaluated in detail, referring to the accident of the Fukushima Dai-ichi Nuclear Power Station of Tokyo Electric Power Company. The plant dynamics computer code: Super-COPD has been used for the evaluation, which has been verified by the analyses of the preliminary test results on the natural circulation in Monju. As a result it was concluded that the natural circulations of the coolant sodium will enable the decay heat removal of the core as far as the sodium coolant flow circuits are intact and secured.