Development of a passive vessel cooling system (VCS) integrated into a reactor building (RB)

Takamatsu, Kuniyoshi ; Funatani, Shumpei*

The objective of this study is to develop a VCS that adopts radiative cooling to passively remove decay heat and residual heat from the RPV under both anticipated and unanticipated natural phenomena and accident conditions. To solve the back-pressure problem at the inlet and outlet of a VCS, the proposed VCS can minimize dependence on fluid-based actuation, such as water or air, and avoid the use of natural circulation or natural convection. This presentation presents the structural concept of the proposed VCS integrated into the reactor building of a commercial HTGR. In addition, the cooling performance of the proposed VCS is evaluated based on experimental and analytical studies conducted to date. The operational strategies of the proposed VCS under normal operation and accident conditions are also discussed.