The Thermal-Hydraulics Behavior Analysis Before the CANDU Fuel Channel Dry-Out

The CANDU 6 nuclear power plant is modeled with SCDAP/RELAP5 code including the heat transport system (HTS), pressure and inventory control system, calandria vessel (CV) and main steam lines, etc. Through simulation of station blackout (SBO), the results obtained before the fuel channel dry-out are illustrated. Before the steam generators (SGs) dry out, the core decay heat could be removed through the SG secondary side, and fuel temperature, pressure of the HTS could keep low. The loss of the HTS inventory results in the fuel channel dry-out, heat-up of the fuel, the calandria and pressure tubes. The moderator temperature remains low in the whole process.