EXPERIMENTAL RESEARCH ON NON-CONDENSABLE GASES EFFECTS IN PASSIVE DECAY HEAT REMOVAL SYSTEM

Passive decay heat removal (PDHR) system is important to the safety of integral pressurized water reactor (IPWR). In small break LOCA sequence, the depressurization of the reactor pressure vessel (RPV) is achieved by the PDHR that remove the decay heat by condensing steam directly through the SGs inside the RPV at high pressure. The non-condensable gases in the RPV significantly weaken the heat transfer capability of PDHR. This paper focus on the non-condensable gas effects in passive decay heat removal system at high pressure. A series of experiments are conducted in the Institute of Nuclear and New Energy Technology test facility with various heating power and non condensable gas volume ratio. The results are significant to the optimizing design of the PDHR and the safety operation of the IPWR.