Study of a loss of coolant accident in a tokamak DEMO

Nakamura, Makoto; Tobita, Kenji; Someya, Yoji; Tanigawa, Hisashi; Araki, Takao*; Watanabe, Kazuhito*; Kittaka, Daigo*; Ishii, Kyoko*; Matsumiya, Hisato*

Recent findings on safety characteristics of a tokamak DEMO reactor are reported in the case where all the coolant water is lost completely and instantaneously. Assuming that there are neither off-site power nor active emergency cooling, we have analyzed temporal histories of the temperatures of the reactor components using the fusion reactor thermo-hydraulic analysis code MELCOR-fus. We have found that even in such an extremely severe case, the temperatures of the vacuum vessel and in-vessel components do not reach their melting points.