Abstract Scope |
The properties of point defects in nuclear fuels are important for fuel performance, since they influence fission gas behaviour, creep, densification, thermal conductivity and properties relevant for manufacturing, such as sintering and grain growth. As part of a continuing effort to develop physics-based predictive fuel performance models we have applied DFT calculations to better understand point defect and fission gas behavior in several different nuclear fuel types, including standard UO2, doped-UO2 and U3Si2. In order to predict concentrations and diffusion rates of point defects and Xe for both in-pile and out-of-pile conditions, the results from DFT calculations are coupled to thermodynamic and kinetic models based on, for example, phase-field and cluster dynamics methodologies, and also complemented by empirical potential simulations. In this talk we will highlight the DFT methodology for UO2 and U3Si2 fuels as well as the approach taken to upscale these results to engineering scale simulations. |