Effect of blanket structure on thermal response to decay heat in LOCA

Gwon, H.; Tanigawa, Hisashi; Nakajima, Motoki; Hirose, Takanori; Kawamura, Yoshinori

It is concerned that the temperature of the blanket would increase excessively due to the decay heat even after the plasma shutdown. In present study, we focuses the relationship between the blanket structures and the passive cooling performance and considers how to effectively mitigate the excessive temperature rising due to the decay heat. The arrangement of both pebble beds and the ribs was changed as a way to relieve the temperature rising. The thermal response characteristics of the modified blanket models were evaluated by using a two-dimensional nuclear-thermal-coupled analysis code, DOHEAT3. The TBR of each model was also evaluated. Based on the results, the useful design policies for blanket were proposed from the viewpoint of the decay heat removal.