Radiation induced athermal diffusivity in uranium mononitride
Journal Article
·
· Journal of Nuclear Materials
- Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
Uranium mononitride (UN) is one of the ceramic nuclear fuel alternatives to oxide fuel considered for light water reactors and advanced reactor designs. Properties like self- and fission gas diffusivity need to be better understood, given that they influence key fuel performance phenomena such as fission gas swelling and release. In particular, the radiation induced athermal (D3) diffusivity remains challenging to accurately predict and has only been sparsely characterized in UN, despite its importance as it likely governs diffusion at the low temperatures this high-thermal-conductivity fuel form may operate. Molecular Dynamics simulations are used to estimate the mean square displacement induced by a primary knock-on atom (PKA) with a given kinetic energy. These results are combined with the PKA energy distributions obtained from binary collision approximation calculations to obtain the displacement due to a particular fission fragment. Finally, this is combined with experimental fission fragment yields to determine the displacement due to an average fission event and, thus, express the athermal diffusivity as a function of the fission rate density. These results are in excellent agreement with available experimental data. In conclusion, a particular importance is given to the understanding and the quantification of the variability of these results.
- Research Organization:
- Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
- Sponsoring Organization:
- USDOE National Nuclear Security Administration (NNSA); USDOE Office of Nuclear Energy (NE)
- Grant/Contract Number:
- 89233218CNA000001; NE0008824
- OSTI ID:
- 2429291
- Report Number(s):
- LA-UR--24-20034
- Journal Information:
- Journal of Nuclear Materials, Journal Name: Journal of Nuclear Materials Vol. 601; ISSN 0022-3115
- Publisher:
- ElsevierCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Ab-initio informed cluster dynamics simulation of self- and Xe diffusivity in uranium mononitride under irradiation
Mechanistic nuclear fuel performance modeling of uranium nitride
Uranium Mononitride (UN) Handbook
Journal Article
·
Sat Dec 06 19:00:00 EST 2025
· Journal of Nuclear Materials
·
OSTI ID:3007527
Mechanistic nuclear fuel performance modeling of uranium nitride
Journal Article
·
Sun Jan 12 19:00:00 EST 2025
· Journal of Nuclear Materials
·
OSTI ID:2500870
Uranium Mononitride (UN) Handbook
Technical Report
·
Mon Sep 09 00:00:00 EDT 2024
·
OSTI ID:2440180