Small rotational fuel-shuffling breed-and-burn sodium-cooled and nitride-fueled fast reactor with LBE reflectors.

In this work, a Rotational Fuel-shuffling Breed-and-Burn fast reactor with nitride fuel and sodium coolant (RFBB-NS) was analyzed. The purpose of the study was to design an RFBB-NS, including assembly duct and control rod assemblies, and to show the feasibility. Monte Carlo simulation code Serpent was used for neutronic and fuel burnup analyses and COMSOL Multiphysics was used for heat removal analysis. The results showed that the practical design of RFBB-NS cannot reach criticality due to the higher presence of absorbing materials such as assembly ducts. Therefore, the core was modified to increase the neutron economy by applying a lead–bismuth reflectors. This allowed the reactor to reach criticality and an equilibrium state after fuel shuffling. Afterward, burnup performance analysis showed that the average fuel discharge burnup was ∼ 298 MWd/kgHM and, that the Pu concentration in the discharge fuel was lower than in previous studies. However, the radiation damage to the cladding material was slightly higher than the constraint value in this study. [ABSTRACT FROM AUTHOR]