Effect of point defects on the thermal conductivity of UO2: molecular dynamics simulations

Technical Report · Tue Jul 21 00:00:00 EDT 2015

DOI:https://doi.org/10.2172/1196177· OSTI ID:1196177

Liu, Xiang-Yang ^[1]; Stanek, Christopher Richard ^[1]; Andersson, Anders David Ragnar ^[1]

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1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

The thermal conductivity of uranium dioxide (UO₂) fuel is an important materials property that affects fuel performance since it is a key parameter determining the temperature distribution in the fuel, thus governing, e.g., dimensional changes due to thermal expansion, fission gas release rates, etc. [1] The thermal conductivity of UO₂ nuclear fuel is also affected by fission gas, fission products, defects, and microstructural features such as grain boundaries. Here, molecular dynamics (MD) simulations are carried out to determine quantitatively, the effect of irradiation induced point defects on the thermal conductivity of UO₂, as a function of defect concentrations, for a range of temperatures, 300 – 1500 K. The results will be used to develop enhanced continuum thermal conductivity models for MARMOT and BISON by INL. These models express the thermal conductivity as a function of microstructure state-variables, thus enabling thermal conductivity models with closer connection to the physical state of the fuel [2].

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC52-06NA25396
• OSTI ID: 1196177
• Report Number(s): LA-UR-15-23625
• Country of Publication: United States
• Language: English

Related Subjects

Materials Science(36)