Preliminary Investigations on the Effect of Cooling Water Boundary Conditions on PCS Performance

The coverage of cooling water film outside the containment shell is one of the most important boundary conditions for Passive Containment Cooling System (PCS) of AP/CAP reactor. The reduced coverage of the water film reduces the heat removal capacity of the containment vessel, which may result in the temperature and pressure within the containment can not be kept at a safe level. In this paper, the effect of cooling water flow rate and water film coverage on the heat removal capacity of PCS was studied experimentally under the loss-of-coolant accident (LOCA). Based on the CAP1400 passive containment water distribution test facility, the cooling water boundary conditions were set according to the combination of different cooling water flow rate and water film coverage rate, and the mass energy was released corresponding to the typical design basis accident condition. The response of parameters within the containment obtained from the test was compared and analyzed with the design condition. The experimental results show that the water film coverage rate has a greater impact on the parameters response within the containment than that of the cooling water flow rate.