Analysis on LOCA for CSR1000

In CSR1000 (Chinese Supercritical Water Cooled Reactor 1000), based on the existing SCAC-CSR1000 code, by incorporating break flow model and passive safety system, CSR1000-DP02 code for LOCA analysis is developed. 50% hot leg break loss of coolant accident (LOCA) is analyzed. The results show that, when LOCA happens, the reactor scrams immediately. The main feed water mass flow, and coolant mass flow of the two fuel channels overall both increase in LOCA. In the flow of passive containment cooling system curve, there is a peak from 2 s to 4 s, and there is a critical flow phenomenon from 5.7 s to 12 s. When LOCA occurs, the cladding temperature gradually decreases, the maximum cladding temperature is below the safety criterion of 1260 °C.