|About this Abstract
|2022 TMS Annual Meeting & Exhibition
|Advanced Characterization and Modeling of Nuclear Fuels: Microstructure, Thermo-physical Properties
|A Predictive Approach to Model Thermal Conductivity Degradation for In-pile UO2
|Joshua Ferrigno, Saqeeb Adnan, Marat Khafizov
|On-Site Speaker (Planned)
As nuclear fuel burn-up increases, its thermal conductivity deteriorates due to the accumulation of defects that lead to increased phonon scattering rates. This results in a rise in the centerline temperature of the fuel pellet, whereby heat generation must be decreased to avoid melting of the fuel. Fuel performance codes are utilized to track this; however, they are based on physical principles that are empirically parametrized. Recently, an effort has been made to develop predictive fuel performance codes. In this presentation, we elaborate on the importance of careful analysis of point defect’s contribution to thermal conductivity. A rate theory model for point defect evolution coupled with the Klemens-Calloway model is used to calculate the change in thermal conductivity of UO2 under irradiation conditions. The model suggests that at higher doses of irradiation the centerline temperature increases, and point defects concentrations are highest near the rim of the fuel pellet.
|Ceramics, Nuclear Materials, Characterization