Studying the effect of assembly homogenization on fuel burn-up for a sodium-cooled fast breeder reactor

Monte Carlo N‐Particle eXtended (MCNPX) computer code was used to design heterogeneous and homogeneous models for the inner and the outer assemblies of a 3600 MWth fast breeder reactor cooled by sodium which is used for next-generation IV reactors. The purpose of the models is to test the adequacy of the lattice homogenization methods for calculations of the neutronic parameters of the assemblies. The multiplication factor, power distributions, and isotopic transmutation were studied and compared using both heterogeneous and homogeneous models. The results indicate that the two models are in good agreement in all cases.