Modeling thermal conductivity in UO2 with BeO additions as a function of microstructure

Abstract New processing methods show promise for improved thermal conductivity in UO2 by the incorporation of a highly-conducting material. Such composites are likely to have anisotropic microstructures which bring new challenges to thermal conductivity simulation but also significant potential for improvement in the thermal performance. This paper presents simulation results for the thermal conductivity of UO2/BeO composites using statistical continuum mechanics. The results successfully capture the microstructural heterogeneity and predict the corresponding anisotropic thermal properties. The application of statistical continuum mechanics to materials design makes it possible to design novel anisotropic fuel pellets with enhanced thermal conductivity in a preferred direction.

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