MCS Analysis of IAEA Lead-Cooled Fast Reactor Core Neutronics Benchmark

Abstract

This paper presents the analysis of an International Atomic Energy Agency (IAEA) Lead-cooled Fast Reactor (LFR) core neutronics benchmark that was proposed under a Coordinated Research Project (CRP) on “Small Reactors without On-site Refueling.” The benchmark problem is based on the RBEC-M core, which is a 900 MWth lead-bismuth cooled conceptual fast reactor developed by the Russian Research Center, “Kurchatov Institute” (RRC KI). The benchmark is proposed to compare the performance of various simulation tools and nuclear data libraries used in the design of LFRs. Based on the foregoing, the continuous energy neutron transport Monte Carlo code MCS under development at Ulsan National Institute of Science and Technology (UNIST) has been used to analyze the RBEC-M benchmark. The purpose of this analysis is to obtain the neutronics parameters, including effective multiplication factor Keff, power profiles and core neutron spectra, defined in the benchmark. The analysis is performed with the ENDF/B-VII.0 and ENDF/B-VII.1 data libraries. The effect on the effective multiplication factor of using several axial and radial depletion zones in the active core region instead of a single depletion zone is analyzed. The effect of treating the cross sections in the unresolved resonance region with and without the Probability Table (PT) is also analyzed.