| About this Abstract |
| Meeting |
2024 TMS Annual Meeting & Exhibition
|
| Symposium
|
Ceramics and Ceramic-based Composites for Nuclear Fission Applications
|
| Presentation Title |
From First-principles, Modeling the Effect of Point-defect Phonon Scattering on the Thermal Conductivity of Oxide Fuels |
| Author(s) |
Erika Nosal, Saqeeb Adnan, Linu Malakkal, Miaomiao Jin, Marat Khafizov |
| On-Site Speaker (Planned) |
Erika Nosal |
| Abstract Scope |
The thermal conductivity of nuclear fuels determines the temperature distribution within a fuel rod, influencing mechanical integrity and fission product retention over its lifetime. Irradiation induced defects alter thermal transport in oxide fuels through phonon scattering. In this work, we use ThO2 as a model for fluorite oxides and investigate the impact of vacancies and interstitials on its thermal conductivity from first-principles. Electronic density-functional calculations are used for the accurate evaluation of interatomic interactions to compute three-phonon and phonon-defect processes. We assess the adequacy of the first-order perturbative Born approximation to model the point-defect phonon scattering rates by contrasting it to the Green’s function T-matrix method. Our results suggest that thorium sublattice defects contribute to a larger reduction in thermal conductivity. We also observe that our predictions depend on the ability to accurately capture interatomic interactions. These findings inform the development of physics based predictive models of oxide fuel behavior. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Nuclear Materials, Characterization, |