Optimization Study of Nuclear Design for a 150 MWe Fast Reactor with Uranium Metallic-Fuel

Abstract

A 150 MWe uranium metallic fueled core design which uses only U—Zr binary fuel not in excess of 20wt% enrichment, is proposed in this study. The selected core design is based on extensive researches for the possible enrichment gains over various design options and in-core fuel management strategies. As a result, an economic and safe uranium metallic fuelled core design is established in the equilibrium cycle. Further optimization has been achieved by applying strategic loading schemes for initial and transition cycles to reach the target equilibrium cycle early. An iterative method has been developed to find initial core enrichment splits. With non-uniform feed enrichments at the initial core adopted, this iterative method shows the core can reach the uranium equilibrium cycle after just five reloads, keeping the feed enrichment unchanged from Cycle 2. Reactivity parameters are evaluated to assure the safety characteristics of this design at both BOC and EOC of the initial core and the equilibrium cycle core. The transition cycle analysis indicated that recycling of self-generated plutonium alone is not sufficient to make the designed reactor a pure plutonium equilibrium core even after 56 reloads.