Presentation Information
[2F09]Evaluation of hydrogen behavior in lower level of BWR reactor building during severe accidents(1) Backgrounds and objectives of the research
*Takumi Nameki1, Kunihiro Tomita2, Yoshihiro Matsuto2, Satoshi Mizuno1, Kimitoshi Yoneda3, Yoshihisa Nishi3, Tomohisa Yuasa3, Miki Saito3, Ryo Morita3 (1. TEPCO HD, 2. ATENA, 3. CRIEPI)
Keywords:
Severe accident,BWR,Reactor building,GOTHIC code,Hydrogen leakage
In NRA, it was recognized that the hydrogen explosion in Unit 3 of the Fukushima Daiichi Nuclear Power Plant was triggered on the lower floor of the reactor building, not on the top floor. In addition, ATENA and BWR utilities have presented an action plan to consider various hydrogen protection measures for voluntary safety improvements, based on the importance of the knowledge gained from the accident. One of the action items in this plan was to “establish methods to evaluate hydrogen retention and diffusion behavior.” The conditions of areas such as ceiling cavities where hydrogen may accumulate in lower floors of the reactor building in the event of a hydrogen leak was evaluated using the thermal-hydraulic analysis code GOTHIC.