Monte Carlo Depletion Analysis of a TRU-Cermet Fuel. Design for a Sodium Cooled Fast Reactor

Monte Carlo depletion has generally not been considered practical for designing the equilibrium cycle of a reactor. One objective of the work here was to demonstrate that recent advances in high performance computing clusters is making Monte Carlo core depletion competitive with traditional deterministic depletion methods for some applications. The application here was to a sodium fast reactor core with an innovative TRU cermet fuel type. An equilibrium cycle search was performed for a multi-batch core loading using the Monte Carlo depletion code Monteburn. A final fuel design of 38% w/o TRU with a pin radius of 0.32 cm was found to display similar operating characteristics to its metal fueled counterparts. The TRU-cermet fueled core has a smaller sodium void worth, and a less negative axial expansion coefficient. These effects result in a core with safety characteristics similar to the metal fuel design, however, the TRU consumption rate of the cermet fueled core is found to be higher than that of the metal fueled core. (authors)