Studies on the behaviour of a passive containment cooling system for the Indian Advanced Heavy Water Reactor

A passive containment cooling system had been proposed for the advanced hea vy water reactor being designed in India. This is to provide long term cool ing for the reactor containment following a loss of coolant accident. The s ystem removes energy released into the containment through through immersed condensers kept in a pool of water. An important aspect of immersed conden ser's working is the potential degradation of immersed condenser's performa nce due to the presence of noncondensable gases. An experimental programme to investigate the passive containment cooling system behaviour and perform ance has been undertaken in a phased manner. In the first phase, system res ponse tests were conducted on a small scale model to understand the phenome na involved. Tests were conducted with constant energy input rate and with varying energy input rate simulating decay heat. With constant energy input rate, pressures in volume V-1 and V-2 reached almost steady value. With va rying energy input rate V-1 pressure dropped below the pressure in V-2. The system could efficiently purge air from V-1 to V-2. The paper deals with t he details of the tests conducted and the results obtained.