Fabrication methods and thermal hydraulics analysis of enhanced thermal conductivity UO₂–BeO fuel in light water reactors

An enhanced thermal conductivity UO₂-BeO composite nuclear fuel was studied. A methodology to generate ANSYS (an engineering simulation software) FEM (finite element method) thermal models of enhanced thermal conductivity oxide nuclear fuels was developed. Two fabrication methods to produce high thermal conductivity UO₂-BeO oxide nuclear fuels were summarized. These two processing routes generated pellets with two different microstructures. The characteristics and microstructures of the fuel are determined for use in FEM thermal models, and the relevant thermal properties for UO₂-BeO fuels by two different fabrication methods were determined. The results showed significant increase in the fuel thermal conductivities. The reactor performance analysis showed that the decrease in centerline temperature was significant at different fuel heights for the UO₂-BeO composite fuel, and thus we can improve nuclear reactors' performance and safety.