| About this Abstract |
| Meeting |
Materials in Nuclear Energy Systems (MiNES) 2021
|
| Symposium
|
Materials in Nuclear Energy Systems (MiNES) 2021
|
| Presentation Title |
Cluster Dynamics Simulations of Fission Gas and Product (Xe, Ag) Diffusivities in TRISO UCO Fuel Kernels
|
| Author(s) |
Xiang-Yang Liu, Christopher Matthews, Wen Jiang, Michael Cooper, Jason Hales, David Andersson |
| On-Site Speaker (Planned) |
David Andersson |
| Abstract Scope |
The UCO fuel kernels used in TRISO particles consist of a uranium dioxide (UO2) and uranium carbide (UC2) mixture. UC2 is added to suppress the formation of carbon monoxide gas, however it also alters the chemistry (non-stoichiometry) of the UO2 matrix by imposing reducing conditions, which is known to influence diffusion parameters governing gas and fission product release. In the present study, density functional theory (DFT) and empirical potential calculations are used to determine the diffusion mechanisms of Xe (fission gas) and Ag (fission product) in UO2 under the reducing conditions generated by the presence of UC2. The calculated diffusion parameters are first used in thermodynamic and kinetic models to predict diffusion for intrinsic conditions, after which the same information is utilized in cluster dynamics simulations to estimate the impact of irradiation on defect transport. The application of the resulting diffusion model in Bison fuel performance simulations is demonstrated. |
| Proceedings Inclusion? |
Undecided |