About this Abstract |
Meeting |
2020 TMS Annual Meeting & Exhibition
|
Symposium
|
Computational Materials Science and Engineering of Materials in Nuclear Reactors
|
Presentation Title |
Molecular Dynamics Studies of Thermal Conductivity Degradation of UO2 due to Dispersed Xe Atoms and Xe Bubbles |
Author(s) |
Weiming Chen, Michael W.D. Cooper, Ziqi Xiao, David Andersson, Xian-Ming Bai |
On-Site Speaker (Planned) |
Weiming Chen |
Abstract Scope |
Thermal conductivity uranium dioxide (UO2) is a critical nuclear fuel
performance property. In reactor fuels, Xe fission gas can be trapped
by vacancies to form dispersed Xe or aggregate to form Xe bubbles,
both of which can significantly impact the fuel thermal transport
properties. In this work, molecular dynamics simulations are conducted
to study the phonon scattering effects by dispersed Xe atoms and Xe
bubbles in UO2. At a given Xe concentration, it is found that the fuel
thermal conductivity increases with bubble size initially then reaches
a saturated value, indicating dispersed Xe atoms can cause more
thermal conductivity reduction than their clustered form. However,
when the Xe content in a bubble is high, the thermal conductivity
reduction is stronger than an empty void. Detailed analysis reveals
that the high bubble pressure can displace bubble surface atoms and
cause additional phonon scattering effect. |
Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |