Extension of the TRANSURANUS plutonium redistribution model for fast reactor performance analysis

The plutonium redistribution model (PUREDI) calculates the steady-state and transient radial plutonium concentration as a function of the radial temperature profile and the time for mixed oxide fuels (MOX). In the context of developing a TRANSURANUS version for Gen-IV fast reactor fuels, PUREDI has been modified and extended to include the effects of the local power density profile and the oxygen-to-metal ratio on plutonium transport. The model has been extensively verified by means of specific numerical tests, and after incorporation in the TRANSURANUS fuel performance code, has been assessed on the basis of post irradiation examinations of the SUPERFACT experiment, showing a good agreement with the experimental data.

► We model the plutonium redistribution in MOX fuel for fast nuclear reactors.
► We examine the effects of burn-up and oxygen-to-metal ratio on Pu migration.
► The model is implemented in the TRANSURANUS fuel performance code.
► Specific numerical tests proved the validity of the assumptions.
► Integral tests show a good agreement of the model with experiments.