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Round-robin test on thermal conductivity measurement of ZnO nanofluids and comparison of experimental results with theoretical bounds.

Lee WH, Rhee CK, Koo J, Lee J, Jang SP, Choi SU, Lee KW, Bae HY, Lee GJ, Kim CK, Hong SW, Kwon Y, Kim D, Kim SH, Hwang KS, Kim HJ, Ha HJ, Lee SH, Choi CJ, Lee JH - Nanoscale Res Lett (2011)

Bottom Line: Ethylene glycol (EG)-based zinc oxide (ZnO) nanofluids containing no surfactant have been manufactured by one-step pulsed wire evaporation (PWE) method.Round-robin tests on thermal conductivity measurements of three samples of EG-based ZnO nanofluids have been conducted by five participating labs, four using accurate measurement apparatuses developed in house and one using a commercial device.The results have been compared with several theoretical bounds on the effective thermal conductivity of heterogeneous systems.

View Article: PubMed Central - HTML - PubMed

Affiliation: Mechanical and Industrial Engineering Department, University of Illinois at Chicago, Chicago, IL, USA. suschoi@uic.edu.

ABSTRACT
Ethylene glycol (EG)-based zinc oxide (ZnO) nanofluids containing no surfactant have been manufactured by one-step pulsed wire evaporation (PWE) method. Round-robin tests on thermal conductivity measurements of three samples of EG-based ZnO nanofluids have been conducted by five participating labs, four using accurate measurement apparatuses developed in house and one using a commercial device. The results have been compared with several theoretical bounds on the effective thermal conductivity of heterogeneous systems. This study convincingly demonstrates that the large enhancements in the thermal conductivities of EG-based ZnO nanofluids tested are beyond the lower and upper bounds calculated using the models of the Maxwell and Nan et al. with and without the interfacial thermal resistance.

No MeSH data available.


Validation of transient hot wire apparatus.
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Figure 3: Validation of transient hot wire apparatus.

Mentions: where N is the data size. Using this method, the measurement uncertainty of transient hot wire apparatus manufactured by each lab was determined to be less than 1.5%. In order to verify the accuracy and the reliability of this experimental system, the thermal conductivity was experimentally measured using deionized water and EG. As shown in Figure 3, a typical THW apparatus calibration with the reference fluids demonstrates that it is possible to measure thermal conductivities with less than 1.5% error, verifying the estimated measurement uncertainty of 1.5%. In Figure 3, the hollow symbols represent the calibration data and the solid symbols are the average value of the calibration data. The solid and dashed lines represent the thermal conductivity of water and EG, respectively [49].


Round-robin test on thermal conductivity measurement of ZnO nanofluids and comparison of experimental results with theoretical bounds.

Lee WH, Rhee CK, Koo J, Lee J, Jang SP, Choi SU, Lee KW, Bae HY, Lee GJ, Kim CK, Hong SW, Kwon Y, Kim D, Kim SH, Hwang KS, Kim HJ, Ha HJ, Lee SH, Choi CJ, Lee JH - Nanoscale Res Lett (2011)

Validation of transient hot wire apparatus.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3211320&req=5

Figure 3: Validation of transient hot wire apparatus.
Mentions: where N is the data size. Using this method, the measurement uncertainty of transient hot wire apparatus manufactured by each lab was determined to be less than 1.5%. In order to verify the accuracy and the reliability of this experimental system, the thermal conductivity was experimentally measured using deionized water and EG. As shown in Figure 3, a typical THW apparatus calibration with the reference fluids demonstrates that it is possible to measure thermal conductivities with less than 1.5% error, verifying the estimated measurement uncertainty of 1.5%. In Figure 3, the hollow symbols represent the calibration data and the solid symbols are the average value of the calibration data. The solid and dashed lines represent the thermal conductivity of water and EG, respectively [49].

Bottom Line: Ethylene glycol (EG)-based zinc oxide (ZnO) nanofluids containing no surfactant have been manufactured by one-step pulsed wire evaporation (PWE) method.Round-robin tests on thermal conductivity measurements of three samples of EG-based ZnO nanofluids have been conducted by five participating labs, four using accurate measurement apparatuses developed in house and one using a commercial device.The results have been compared with several theoretical bounds on the effective thermal conductivity of heterogeneous systems.

View Article: PubMed Central - HTML - PubMed

Affiliation: Mechanical and Industrial Engineering Department, University of Illinois at Chicago, Chicago, IL, USA. suschoi@uic.edu.

ABSTRACT
Ethylene glycol (EG)-based zinc oxide (ZnO) nanofluids containing no surfactant have been manufactured by one-step pulsed wire evaporation (PWE) method. Round-robin tests on thermal conductivity measurements of three samples of EG-based ZnO nanofluids have been conducted by five participating labs, four using accurate measurement apparatuses developed in house and one using a commercial device. The results have been compared with several theoretical bounds on the effective thermal conductivity of heterogeneous systems. This study convincingly demonstrates that the large enhancements in the thermal conductivities of EG-based ZnO nanofluids tested are beyond the lower and upper bounds calculated using the models of the Maxwell and Nan et al. with and without the interfacial thermal resistance.

No MeSH data available.