A study on the optimization of integral fuel burnable absorbers using deterministic methods

Abstract

A deterministic fuel management study was performed to optimize Integral Fuel Burnable Absorber (IFBA) designs for Pressurized Water Reactors (PWRs). Penn State's IFBA designs were compared to Westinghouse's generic IFBA designs of 64, 80, and 160 IFBA pins per assembly. It was found deterministically that the current generic Westinghouse designs of 64 and 80 IFBA may be improved upon, but the typical 160 IFBA design by Westinghouse was not sufficiently improved upon. The results indicate it is not necessary to use large numbers of IFBA pins per assembly nor is it necessary to use exceedingly high boron enrichment in the IFBA pins. This deterministic study was performed as part of a genetic algorithm optimization study which used IFBA fuel designs and CASMO-3. The Penn State IFBA pin placement designs with the IFBA loaded toward the center of the assembly and surrounding the control rod guide tubes proved to be very successful. The Penn State IFBA pin designs with 64 and 80 IFBA pins showed significant improvement over the generic vendor designs, which have IFBA placed towards the assembly periphery. The Penn State 64 and 80 IFBA designs reduced the maximum peak pin NP by as much as 5% over the vendor's IFBA configurations.