Resonance Calculation of FCM Fuel Based on the Global-Local Method

Fully ceramic microencapsulated fuels is a promising potential fuel for pressurized water reactors because of its inherent safety, but double heterogeneity (DH) brings challenges to the neutronic calculation. In this paper, the Hébert model is applied to the global-local resonance method to solve DH, in which the Dancoff factor obtained by the neutron current method is used to transform the coupled fuel pins in the reactor into multiple independent one-dimensional equivalent cylindrical fuel pins. Then, the Hébert model and the hyperfine group method are used to perform the resonance self-shielding calculation in these independent pins. The Sanchez-Pomraning method coupled with the Method of Characteristics (Sanchez-MOC) method is introduced to the two-dimensional/one-dimensional transport module to realize the subsequent whole-core DH transport calculations. The proposed method has been implemented in the high-fidelity neutronics code NECP-X and tested with a set of cases. The results show good agreement with the Monte Carlo reference values for the reactivity and self-shielding cross sections.