PARTICIPATION IN THE OECD/NEA BENCHMARKS FOR LWRs MODELLING USING SCALE6.2 CODE

摘要

With a large number of light water reactor (LWRs) around the world, there is an increasing interest in the development of Best-estimate computer codes for safety analysis research. That enable to reduce uncertainties in calculations and increase the results reliability. Moreover, sensitivity analysis and code validation are needed. This paper presents a cross section calculation with its uncertainty analysis in SCALE-6.2 (actually in version beta 4) for two Boiling Water Reactors (BWRs) simulations. This work is related with OECD/NEA UAM-Benchmark for uncertainties analysis in LWRs best-estimate modelling, coupling multi-physics and multi-scale analysis. The objective is to determine and quantify uncertainty in all steps of calculation and propagate these uncertainties in LWR whole system. Based on measured data from Peach Bottom 2 (PB-2) and Oskarshamn-2 (O-2) nuclear power plants, there were performed a steady-state calculations for a fuel element of BWRs, in two different configurations at Hot Zero Power state. Neutronics calculations were accomplished with the computation of energy collapsed and homogenized macroscopic cross-sections through SCALE-6.2. The deterministic lattice modelling is carried out using TRITON/NEWT module for transport calculations, while the uncertainties and sensitivity analysis of cross-sections calculation has been performed using the SAMPLER module, which uses stochastic sampling techniques of cross-sections perturbations. The results are presented in this work. It was found a good correspondence between the cross-sections results and references data, and a sensitivity analysis has been conducted to confirm the validation of the two modules and to study the influence of the uncertainties in the fuel element calculation.