Fuel Behavior in Simulated RIA under High Pressure and Temperature Coolant Condition

Abstract

Fuel behavior in simulated reactivity initiated accident (RIA) was studied under high pressure and temperature coolant condition of LWR operating environment. Test fuel rods were pulse-irradiated in the Nuclear Safety Research Reactor (NSRR) to simulate transient power generations at RIAs. From the results, it was clarified that the cladding collapsed under high external pressure but that the basic mechanisms and threshold enthalpies of incipient fuel failure were not different from those observed in the tests conducted under atmospheric pressure, room temperature and stagnant condition.