Safty assessment of RUFIC fuel during the postulated accident of CANDU-6 feeder breaks

The safety assessment for the feeder breaks, as one of the postulated design basis events, was performed for a CANDU 6 reactor loaded with CANFLEX-RU fuel bundles. According to the assessment results, the fuel channel integrity, molten mass, and fission products release from failed fuel for the stagnation and off-stagnation feeder breaks are assured to be a more enhanced safety for CANFLEX-RU bundle, compared to the 37-element bundle. Particularly, the amounts of CANFLEX-RU's molten mass and fission products release prior to channel failure in the case of stagnation feeder break are significantly reduced by 35% and 40%, respectively, compared to those of the 37-element bundle. With only the results for the postulated accident of feeder breaks, it cannot be judged that the same conclusion can be applied to other design basis events. Therefore, other severe design basis events which would result in fuel failure should be assessed in further study