0
Technical Brief

A Density Functional Theory Study on the Diffusion of Fission Gas Atoms in Uranium Dioxide

[+] Author and Article Information
Qiang Zhao

School of Nuclear Science and Engineering North China Electric Power University Beijing 102206, P.R. China
qzhao@ncepu.edu.cn

Zheng Zhang

School of Nuclear Science and Engineering North China Electric Power University Beijing 102206, P.R. China
zzhang@ncepu.edu.cn

Xiaoping Ouyang

School of Nuclear Science and Engineering North China Electric Power University Beijing 102206, P.R. ChinaNorthwest Institute of Nuclear Technology Xi’an 710024, P.R. ChinaXiangtan University Xiangtan Hunan 411105, P.R. China
oyxp2003@aliyun.com

1Corresponding author.

ASME doi:10.1115/1.4039885 History: Received October 31, 2017; Revised March 20, 2018

Abstract

Uranium dioxide (UO2) is the typical fuel that is used in the current nuclear power plant, fission gas atoms are produced during and after the nuclear reactor operation, and the fis- sion gas atoms have a significant effect on the performance of UO2 fuel in nuclear reactor. In this paper, we investigated the diffusion of the fission gas atoms in the UO2 fuel by using the first-principles calculation method based on the density functional theory (DFT). The results indicate that the volume of the UO2 cell increased when there is a fission gas atom enter in the UO2 supercell; the elastic properties of UO2 are in good agreement with other simulation results and exper- imental data, and the fission gas atoms make the ductility of UO2 decreased; fission gas atoms prefer to occupy the octahedral interstitial site (OIS) over the uranium vacancy site and the oxygen vacancy site, and the oxygen vacancy site is the most difficult occupied site due to the formation of an oxygen vacancy is more difficult than that of the ura- nium vacancy; the diffusion barrier of a He atom in the UO2 supercell is smaller than that of a oxygen atom, that means that the diffusion of the He atom in UO2 fuel is stronger than that of the oxygen atom. Our work may shed some light on the formation mechanism of the bubbles caused by the fission gas atoms in the UO2 fuel.

Copyright (c) 2018 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In