Modelling and Analysis of a (Th,Pu)O2 Fuel Bundle Experiment in ZED-2 Using SCALE6 and TSUNAMI

Abstract

TSUNAMI, a sensitivity and uncertainty analysis tool, was applied to study the intrinsic physics parameters of a (Th,Pu)O₂ fuel bundle experiment in ZED-2. This paper focuses on the investigation of moderator purity reactivity (MPR) by modelling the (Th,Pu)O₂ experiment in two cases with slightly different moderator purity. TSUNAMI analysis derived reaction-specific sensitivity coefficients since they must be taken into account in the calculation of k_eff and MPR uncertainties. Isotopes in the (Th,Pu)O₂ bundle were found to be the major uncertainty contributors in MPR and they have greater keff sensitivity responses in the less pure ZED-2 model.