New Reactor Cavity Cooling System (RCCS) having passive safety features, 1; Experimental conditions of a scale-down heat removal test facility for comparison with a real RCCS

Takamatsu, Kuniyoshi  ; Matsumoto, Tatsuya*; Morita, Koji*

After Fukushima Daiichi nuclear disaster by TEPCO, a cooling system to prevent core damage became more important from the perspective of defense in depth. Therefore, a new, highly efficient RCCS with passive safety features without a requirement for electricity and mechanical drive is proposed. Employing the air as the working fluid and the ambient air as the ultimate heat sink, the new RCCS design strongly reduces the possibility of losing the heat sink for decay heat removal. Now, we conduct experiments with the scale-down heat removal test facility to understand the heat-transfer characteristics and assessed effect of radiation quantitatively. Moreover, after considering experimental conditions for the scale-down heat removal test facility to reproduce radiation and natural convection in the new RCCS, we can also find decision technique for the experimental conditions.