In order to evaluated the effectiveness of post incident safety devices for light water power reactors, experiments were performed on the cooling efficiency of spray, the flow rate of saturated water from a pressure vessel, the heat transfer of a container wall surface, and the cooling efficiency of container spray, and the following results were obtained:
(1) Measurements of the temperature changes caused on heated rods (model fuel assembly) by spray cooling contributed to the formulation of a proposed theory to explain the temperature changes.
(2) The relationships existing between dry-out heat out-put and spray flow rate for stationary core spray cooling were obtained.
(3) The flow rate of saturated water from a model pressure vessel was measured and compared with Moody's theoretical results.
(4) The heat transfer coefficient of a container wall surface was measured with an apparatus installed in a model container and the variation of heat transfer with time and with inner-pressure of the container was determined.
(5) The relationship between cooling efficiency of container spray and inner-pressure of the container was obtained from experiments with a model container.
