DARWIN2 LOW BURNUP VALIDATION FOR BURNUP CREDIT USING SFCOMPO PIE DATABASE - VERIFICATION OF ICF VALUES

摘要

The DARWIN package, developed by the CEA and its French partners (AREVA and EDF), provides the parameters required for fuel cycle applications, especially fuel inventory. It is widely used in the French Burnup Credit (BUC) calculation route, based on the connection of the depletion code DARWIN and the Criticality-Safety Package CRISTAL. The experimental validation process of BUC nuclides provided by DARWIN2.3 package consists in the comparison between JEFF-3.1.1-based calculated values of isotopic concentrations and experimental values obtained from the chemical analysis of PWR fuel rod cuts. As a complement to the extensive validation using the French PIE database, specific PIE data chosen for their quality were selected and analyzed in the SFCOMPO database of NEA. A set of 56 samples chosen in PWR-UO_2 experiments was selected, with initial ~(235)U enrichment between 2.7% and 4.1% and local burnup estimated from ~(l48)Nd measurement varying between 7 and 35 GWd/tHM. This paper provides an overview of calculation - experiment comparison obtained in Takahama-3 17x17, Trino-Vercellese 15x15 and Obrigheim 14x1 for uranium, plutonium isotopes, as well as available fission products contributing to the assembly reactivity. Consistent biases compared to SCALE5 results were obtained. From these results, an analysis is driven using 15 selected samples with low burnup, selected among asymptotic rods of irradiated fuels at 1 or 2 cycles. This paper shows the consistency of the calculation - experiment biases obtained with DARWIN2.3 towards previously defined penalized biases used for the Isotopic Correction Factors (ICF) in BUC applications.