Implementing first principles calculations of defect migration in a fuel performance code for UN simulations

Journal Article · Tue Sep 01 04:00:00 EDT 2009 · Journal of Nuclear Materials, 393(2):292-299

DOI:https://doi.org/10.1016/j.jnucmat.2009.06.016· OSTI ID:1001527

Kotomin, E A; Mastrikov, Yuri A; Rashkeev, Sergey N; Van Uffelen, Paul

Results are reported of first principles VASP supercell calculations of basic defect migration in UN nuclear fuels. The collinear interstitialcy mechanism of N migration is predicted to be energetically more favourable than direct [0 0 1] hops. It is also found that U and N vacancies have close migration energies, and O impurities accelerate migration of N vacancies nearby. These values are both in qualitative agreement with the effect of oxygen on the reduction of the activation energy for thermal creep reported in the literature, as well as in quantitative agreement with the experimental data when taking into account the uncertainties. The migration energies have been implemented in the thermal creep model of the TRANSURANUS fuel performance code. Therefore a concrete example is provided of how first principles computations can contribute directly to improve the design tools of advanced nuclear fuels, e.g. the predictions reveal a limited effect of oxygen on the thermo-mechanical performance of nitride fuels under fast breeder reactor (FBR) normal operating conditions.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1001527
• Journal Information: Journal of Nuclear Materials, 393(2):292-299, Journal Name: Journal of Nuclear Materials, 393(2):292-299
• Country of Publication: United States
• Language: English

Related Subjects

Environmental Molecular Sciences Laboratory