Experimental Measurement and Numerical Modeling of the Effective Thermal Conductivity of TRISO Fuel Compacts
Abstract
Accurate modeling capability of thermal conductivity of tristructuralisotropic (TRISO) fuel compacts is important to fuel performance modeling and safety of Generation IV reactors. To date, the effective thermal conductivity (ETC) of tristructuralisotropic (TRISO) fuel compacts has not been measured directly. The composite fuel is a complicated structure comprised of layered particles in a graphite matrix. In this work, finite element modeling is used to validate an analytic ETC model for application to the composite fuel material for particlevolume fractions up to 40%. The effect of each individual layer of a TRISO particle is analyzed showing that the overall ETC of the compact is most sensitive to the outer layer constituent. In conjunction with the modeling results, the thermal conductivity of matrixgraphite compacts and the ETC of surrogate TRISO fuel compacts have been successfully measured using a previously developed measurement system. The ETC of the surrogate fuel compacts varies between 50 and 30 W m ^{1} K ^{1} over a temperature range of 50600°C. As a result of the numerical modeling and experimental measurements of the fuel compacts, a new model and approach for analyzing the effect of compact constituent materials on ETC is proposed that can estimate the fuel compactmore »
 Authors:
 Utah State Univ., Logan, UT (United States). Mechanical and Aerospace Engineering Dept.
 Idaho National Lab. (INL), Idaho Falls, ID (United States)
 Publication Date:
 Research Org.:
 Idaho National Lab. (INL), Idaho Falls, ID (United States)
 Sponsoring Org.:
 USDOE Office of Nuclear Energy (NE)
 OSTI Identifier:
 1177669
 Report Number(s):
 INL/JOU1433945
Journal ID: ISSN 00223115; TRN: US1500087
 DOE Contract Number:
 AC0705ID14517
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Nuclear Materials; Journal Volume: 458
 Country of Publication:
 United States
 Language:
 English
 Subject:
 11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS; THERMAL CONDUCTIVITY; GRAPHITE; COMPACTS; MATRIX MATERIALS; Nuclear Fuels; Fuel Particles; SIMULATION; APPROXIMATIONS; LAYERS; Temperature Range 02730400 K; Temperature Range 04001000 K; ANISOTROPY; EXPERIMENT; GUARDEDCOMPARATIVE HEAT FLOW TECHNIQUE; NUMERICAL; TRISO
Citation Formats
Folsom, Charles, Xing, Changhu, Jensen, Colby, Ban, Heng, and Marshall, Douglas W. Experimental Measurement and Numerical Modeling of the Effective Thermal Conductivity of TRISO Fuel Compacts. United States: N. p., 2015.
Web. doi:10.1016/j.jnucmat.2014.12.042.
Folsom, Charles, Xing, Changhu, Jensen, Colby, Ban, Heng, & Marshall, Douglas W. Experimental Measurement and Numerical Modeling of the Effective Thermal Conductivity of TRISO Fuel Compacts. United States. doi:10.1016/j.jnucmat.2014.12.042.
Folsom, Charles, Xing, Changhu, Jensen, Colby, Ban, Heng, and Marshall, Douglas W. 2015.
"Experimental Measurement and Numerical Modeling of the Effective Thermal Conductivity of TRISO Fuel Compacts". United States.
doi:10.1016/j.jnucmat.2014.12.042.
@article{osti_1177669,
title = {Experimental Measurement and Numerical Modeling of the Effective Thermal Conductivity of TRISO Fuel Compacts},
author = {Folsom, Charles and Xing, Changhu and Jensen, Colby and Ban, Heng and Marshall, Douglas W.},
abstractNote = {Accurate modeling capability of thermal conductivity of tristructuralisotropic (TRISO) fuel compacts is important to fuel performance modeling and safety of Generation IV reactors. To date, the effective thermal conductivity (ETC) of tristructuralisotropic (TRISO) fuel compacts has not been measured directly. The composite fuel is a complicated structure comprised of layered particles in a graphite matrix. In this work, finite element modeling is used to validate an analytic ETC model for application to the composite fuel material for particlevolume fractions up to 40%. The effect of each individual layer of a TRISO particle is analyzed showing that the overall ETC of the compact is most sensitive to the outer layer constituent. In conjunction with the modeling results, the thermal conductivity of matrixgraphite compacts and the ETC of surrogate TRISO fuel compacts have been successfully measured using a previously developed measurement system. The ETC of the surrogate fuel compacts varies between 50 and 30 W m1 K1 over a temperature range of 50600°C. As a result of the numerical modeling and experimental measurements of the fuel compacts, a new model and approach for analyzing the effect of compact constituent materials on ETC is proposed that can estimate the fuel compact ETC with approximately 1520% more accuracy than the old method. Using the ETC model with measured thermal conductivity of the graphite matrixonly material indicate that, in the composite form, the matrix material has a much greater thermal conductivity, which is attributed to the high anisotropy of graphite thermal conductivity. Therefore, simpler measurements of individual TRISO compact constituents combined with an analytic ETC model, will not provide accurate predictions of overall ETC of the compacts emphasizing the need for measurements of composite, surrogate compacts.},
doi = {10.1016/j.jnucmat.2014.12.042},
journal = {Journal of Nuclear Materials},
number = ,
volume = 458,
place = {United States},
year = 2015,
month = 3
}

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