Fully ceramic micro-encapsulated (FCM) fuels generate double heterogeneity (DH) challenging greatly for classical resonance self-shielding calculation method. New methodologies have been proposed and verified in this research. The target of this study is to provide homogeneous multi-group cross sections reflecting the effect of DH. Embedded Self-Shielding Method (ESSM) [1] was selected to perform resonance self-shielding calculation. Therefore, Monte Carlo code MVP [2] which is capable of well modeling the stochastic dispersed tri-structural isotropic (TRISO) coated fuel particle throughout carbide matrix and method of characteristics (MOC) were chosen to develop the heterogeneous resonance integral (RI) tables for DH problems. Benchmark problems from reference [3] were provided to verify the new methodologies. The results show that ESSM with RI tables from MVP and MOC could well address the resonance calculation for DH problems.
Validation of UNIST Monte Carlo code MCS for criticality safety calculations with burnup credit through MOX criticality benchmark problems
