Abstract
The conventional cask storage facility has a high ceiling. In order to shorten the construction period and reduce the cost, a new type of cask storage facility is proposed. Its ceiling height is made low and the stack is set up on the opposite side of the air inlet through the storage area, giving what we call a “stack-type facility”. The flow pattern in the storage area of this facility is then different from that of the conventional facility and the heat removal performance of a stack-type facility has been studied. Simulation experiment by using a 1/5 reduced scale model was performed, and thermal-hydraulic phenomena of the facility were investigated. Following results were obtained by this study:
1) The ceiling height hardly influences the heat removal characteristic of the casks. On the other hand, the ceiling temperature is so much influenced by the ceiling height.
2) The stack height directly influences the heat removal of the casks. The stack height by which heat generation of casks could be safely removed was estimated.
3) There are two kinds of flows in the storage area of the facility, one is a upward flow induced by buoyancy force on the cask surface, and the other is a horizontal flow induced by the stack effect. These flows contribute to the cooling of casks.
