Effects of Edge Dislocations on Thermal Transport in UO₂

Abstract

Molecular-dynamics simulations are used to characterize the effects of dislocations on the thermal transport properties of UO2. Microstructures with various dislocation densities of the order of 1016 m-2 are simulated at temperatures between 800 and 1600 K. The effects of dislocations on the thermal-transport properties are found to be independent on temperature, consistent with the classic Klemens-Callaway analysis. The effect of dislocation density is also quantified. The simulation results are also fit to the pertinent part of the empirical formula for the thermal conductivity used in the FRAPCON fuel-performance code, which gives the overall effects of temperature and dislocation effects on thermal conductivity. The fitted results can be well-described within this formalism, indicating that the results of molecular-dynamics simulations can be used as a reliable source of parameters for models at longer length scales.

Department(s)

Physics

Keywords and Phrases

Dislocation densities; Dislocation effects; Effect of dislocations; Effects of temperature; Empirical formulas; Length scale; Molecular dynamics simulations; Thermal transport; Thermal transport properties; Computer simulation; Dynamics; Thermal conductivity

International Standard Serial Number (ISSN)

0022-3115

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2013 Elsevier, All rights reserved.

Publication Date

01 Mar 2013

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