Evaluation of thermal conductivity of hyperstoichiometric UO2+x by molecular dynamics simulation

被引：17

作者：

Yamasaki, Sho ^{[1
]}

Arima, Tatsumi ^{[1
]}

Idemitsu, Kazuya ^{[1
]}

Inagaki, Yaohiro ^{[1
]}

机构：

[1] Kyushu Univ, Fac Engn, Inst Environm Syst, Fukuoka 8128581, Japan

来源：

INTERNATIONAL JOURNAL OF THERMOPHYSICS | 2007年 / 28卷 / 02期

关键词：

equilibrium molecular dynamics simulation; heat capacity; hyperstoichiometric uranium oxide; phonon mean free path; thermal conductivity;

D O I：

10.1007/s10765-007-0170-6

中图分类号：

O414.1 [热力学];

学科分类号：

摘要：

The thermal conductivity of UO2+x has been investigated by an equilibrium molecular dynamics (EMD) simulation up to 2000 K using the Born-Mayer-Huggins interatomic potential with the partially ionic model. In the present EMD system with the Green-Kubo method, the thermal conductivity was determined by the auto-correlation functions of energy and charge currents and the cross-coupling term. The thermal conductivity of UO2+x decreased with an increase of x and temperature. Its temperature dependence was relatively small for large x values, which was attributed to phonon scattering by excess oxygens. In addition, the heat capacity was calculated using the phonon-level density deduced by the velocity auto-correlation function for constituent ions. The phonon velocity was also evaluated by the phonon- dispersion relationship. Using these thermal properties obtained by EMD calculations, the effect of excess oxygens on the phonon mean free path was discussed.

引用

页码：661 / 673

页数：13

共 29 条

[11]

Hirao K., 1994, MAT DESIGN USING PER

[12] Molecular dynamics simulation of gadolinia-doped ceria [J].

Inaba, H ;

Sagawa, R ;

Hayashi, H ;

Kawamura, K .

SOLID STATE IONICS, 1999, 122 (1-4) :95-103

[13]

Kittel C., 2018, INTRO SOLID STATE PH

[14] Molecular dynamics study of mixed oxide fuel [J].

Kurosaki, K ;

Yamada, K ;

Uno, M ;

Yamanaka, S ;

Yamamoto, K ;

Namekawa, T .

JOURNAL OF NUCLEAR MATERIALS, 2001, 294 (1-2) :160-167

[15] A MOLECULAR-DYNAMICS STUDY OF THE THERMAL-CONDUCTIVITY OF CAF2 AND UO2 [J].

LINDAN, PJD ;

GILLAN, MJ .

JOURNAL OF PHYSICS-CONDENSED MATTER, 1991, 3 (22) :3929-3939

[16] A pragmatic approach to modelling thermal conductivity of irradiated UO2 fuel: Review and recommendations [J].

Lucuta, PG ;

Matzke, H ;

Hastings, IJ .

JOURNAL OF NUCLEAR MATERIALS, 1996, 232 (2-3) :166-180

[17] THE THERMAL-EXPANSION OF SOLID UO2 AND (U, PU) MIXED OXIDES - A REVIEW AND RECOMMENDATIONS [J].

MARTIN, DG .

JOURNAL OF NUCLEAR MATERIALS, 1988, 152 (2-3) :94-101

[18] THERMAL CONDUCTIVITY OF NEARLY STOICHIOMETRIC SINGLE-CRYSTAL AND POLYCRYSTALLINE UO2 [J].

MOORE, JP ;

MCELROY, DL .

JOURNAL OF THE AMERICAN CERAMIC SOCIETY, 1971, 54 (01) :40-&

[19] Thermal conductivity of uranium dioxide by nonequilibrium molecular dynamics simulation [J].

Motoyama, S ;

Ichikawa, Y ;

Hiwatari, Y ;

Oe, A .

PHYSICAL REVIEW B, 1999, 60 (01) :292-298

[20]

Olander D.R., 1976, TID26711P1

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