Preliminary Sensitivity and Uncertainty Analysis of Accident Tolerant Fuel in SMR

As the technology of small modular reactor (SMR) becomes mature, its safety is getting more attention. In recent research of accident tolerant fuel (ATF) such as the U3Si2 used in a large commercial pressurized water reactor can significantly improve the safety of the core due to its high thermal conductivity and good physicochemical properties. Therefore, applying the ATF in the SMR can also enhance its safety. The mPower with a thermal power output of 530 MW designed by B&W company is selected as one of the SMR. In the design and production process of fuel rods, the design and manufacturing parameters such as fuel pellet diameter, inner diameter of cladding, fuel pellet density and other parameters have uncertain factors. These factors affect the results of effective multiplication factor (keff). In this work, we carried out preliminary sensitivity and uncertainty analysis of the U3Si2 with accident tolerant cladding (FeCrAl, SiC) in mPower using SEPRENT and DAKOTA. Sensitivity analysis performed the relative importance of each input parameters for different ATF combination. Uncertainty analysis gave the tolerance range and uncertainty for different ATF combination.