Experimental research and analysis of VVER fuel composition with erbium oxide absorbers

NRC Kurchatov Institute's critical facility performed a series of experiments to study neutron characteristics of water-uranium compositions that contains fuel pins with uranium enriched up to 6.5 wt% of U-235 and erbium oxide (Er2O3) absorbers. Sizes, shapes, and compositions were defined to model uranium-erbium fuel considered for VVER extended fuel cycles. We believe the experimental results are valid for verifying and validating the computer codes employed to research and design advanced fuel cycles. The paper describes the main implemented fuel compositions and presents experimental results for criticality parameters and neutron flux distributions. The Monte Carlo code MCU-PD and the spectral code TVS-M were applied for the computational analysis. Both of these codes are used for VVER fuel cycles design. Results of the calculations of the primary neutron characteristics are compared to the experimental values. •Novel experimental study of VVER fuel with erbium oxide performed at a critical facility of Kurchatov Institute.•A full description of four elemental fuel compositions is presented.•Experimental results for critical moderator level, reactivity coefficient and neutron flux distribution are available.•Analysis employing Monte Carlo and spectral codes shows good agreement and are aligned to previous experience.•New experimental data is necessary for the v&v process while implementing uranium-erbium fuel for VVER.