|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Advanced Characterization and Modeling of Nuclear Fuels: Microstructure, Thermo-physical Properties
||Mesoscale Modeling of Effective Thermal Conductivity in U-Zr Fuels with Heterogeneous Phases
||Weiming Chen, Xian-Ming Bai
|On-Site Speaker (Planned)
Uranium-zirconium (U-Zr) alloys are promising candidate fuels for next-generation fast reactors. Depending on the temperature, U-Zr fuels can contain multiple phases, which affect many fuel properties including thermal conductivity. Many existing U-Zr thermal conductivity models are empirical and do not contain the microstructure- or phase-dependent information. In this work, we used mesoscale modeling in the MOOSE framework to model the effective thermal conductivities of U-Zr alloys containing alpha-U + delta-UZr2 lamellar structures. We found that the interface thermal resistance (Kapitza resistance) should be properly taken into account in order to predict the effective thermal conductivity of such a heterogeneous microstructure accurately. Based on the mesoscale modeling results, we developed a temperature- and geometry-dependent Kapitza resistance model for the lamella structure. By including this model in the mesoscale modeling, the effective thermal conductivities of a number of lamellar structures can be reasonably predicted at a wide range of temperatures.
||Nuclear Materials, Modeling and Simulation, Other