SAFETY ANALYSIS OF LOSS OF COOLANT ACCIDENT EVENTS FOR THE CANADIAN SUPERCRITICAL WATER-COOLED REACTOR

Analyses of the safety system response to postulated loss-of-coolant-accident (LOCA) events were performed using the SCTRAN safety analysis computer code for the Canadian supercritical water-cooled reactor (SCWR) concept. These analyses covered both the cold-leg break and hot-leg break LOCA scenarios. All relevant passive safety systems, such as automatic depressurization system, accumulator, and gravity-driven cooling system, were included in the simulation. The simulation for the cold-leg break LOCA showed 2 cladding temperature peaks over the duration of 100 seconds. Over the range of break sizes (i.e., 25%, 50%, and 100%) investigated in this study, the first peak cladding temperature predicted for the 25% break size is higher than that for the 100% break size, but the second peak cladding temperature predicted for the 25% break size is lower than that for the 100% break size. Simulations of the hot-leg break LOCA have resulted in only 1 cladding temperature peak, which was not significantly affected ...