Passive Containment Cooling System (PCCS) Containment Vessel Water Distribution / Heat Transfer Tests

At the Westinghouse Science and Technology Center in Pittsburgh, containment cooling was studied. First, a flat plate ... three feet wide and six feet high ... that met the specifications for the containment was built. It was used to examine basic thermodynamics. Water ran across its surface and hard data on the heat transfer was obtained under varying conditions. The data was used in containment code safety analysis.

A much larger test device was then built-- a 24-foot high, three-foot-diameter model of the containment. This time, with steam inside, air was moved over the outside as water flowed across the surface. This larger-scale, more-detailed testing provided additional data for computer codes. Then an even larger model was built: a one-eighth scale model of the containment. Again, the entire range of passive safety actions was studied-- using various internal conditions and external air and humidity values. Testing with water applied to the top of the external surface was used, along with testing with a dry surface. This exhaustive, real-world testing shows that the theory of passive containment cooling is valid. Even the toughest internal and external conditions -- and combinations of both -- did an adequate job of cooling. This is a cooling concept that does the job perfectly, relying solely on natural forces.