Cross Sections Generation and SPH Correction Methods for Deterministic Code Simulation of the Westinghouse LFR Design

This paper presents a neutronic analysis of a simplified version of the Westinghouse LFR. The study focuses on the approach for generating the multi-group cross sections, obtained from Monte Carlo simulations, that are then used in the full-core calculations with deterministic codes. Specifically, this work investigates the possibility of using a set of sub-assembly models instead of a full-core model for the cross-section generation when multiple core configurations are considered, to exploit the resulting advantages. The potential of applying the Super Homogenization method (SPH), trough which SPH correction factors are generated and used to improve the accuracy of results obtained by deterministic models, is also explored. The use of super-cell models for non-multiplying regions and how these can be used to apply SPH correction factors to material data in regions that cause significant neutron flux gradients is also illustrated. The values of 𝑘𝑘eff and the power density distribution show good agreement with the Serpent reference results after cross-section correction, while the kinetic parameters 𝛽eff and Λeff seem not affected by the SPH correction method.