Multiscale development of a fission gas thermal conductivity model: Coupling atomic, meso and continuum level simulations

被引：36

作者：

Tonks, Michael R. ^{[1
]}

Millett, Paul C. ^{[1
]}

Nerikar, Pankaj ^{[2
]}

Du, Shiyu ^{[2
]}

Andersson, David ^{[2
]}

Stanek, Christopher R. ^{[2
]}

Gaston, Derek ^{[1
]}

Andrs, David ^{[1
]}

Williamson, Richard ^{[1
]}

机构：

[1] Idaho Natl Lab, Idaho Falls, ID 83415 USA

[2] Los Alamos Natl Lab, Mat Sci & Technol Div, Los Alamos, NM 87545 USA

来源：

JOURNAL OF NUCLEAR MATERIALS | 2013年 / 440卷 / 1-3期

关键词：

IRRADIATED UO2 FUEL; MOLECULAR-DYNAMICS; URANIUM-DIOXIDE; NUCLEAR-FUEL; THERMOPHYSICAL PROPERTIES; RELEASE; HELIUM;

D O I：

10.1016/j.jnucmat.2013.05.008

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Fission gas production and evolution significantly impact the fuel performance, causing swelling, a reduction in the thermal conductivity and fission gas release. However, typical empirical models of fuel properties treat each of these effects separately and uncoupled. Here, we couple a fission gas release model to a model of the impact of fission gas on the fuel thermal conductivity. To quantify the specific impact of grain boundary (GB) bubbles on the thermal conductivity, we use atomistic and mesoscale simulations. Atomistic molecular dynamic simulations were employed to determine the GB thermal resistance. These values were then used in mesoscale heat conduction simulations to develop a mechanistic expression for the effective GB thermal resistance of a GB containing gas bubbles, as a function of the percentage of the GB covered by fission gas. The coupled fission gas release and thermal conductivity model was implemented in Idaho National Laboratory's BISON fuel performance code to model the behavior of a 10-pellet LWR fuel rodlet, showing how the fission gas impacts the UO2 thermal conductivity. Furthermore, additional BISON simulations were conducted to demonstrate the impact of average grain size on both the fuel thermal conductivity and the fission gas release. Published by Elsevier B.V.

引用

页码：193 / 200

页数：8

共 38 条

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