Thermal conductivity of a wide range of alternative refrigerants measured with an improved guarded hot-plate apparatus

A guarded hot plate apparatus was used to generate comprehensive sets of thermal conductivity for two types of soils, namely Ottawa sand and Richmon Hill clay-loam, for temperature variation from 2 to 92°C and moisture content variation from complete dryness to full saturation with measurement errors of less than 3%. Numerical simulation of heat transfer within the apparatus with sample inside was performed to validate the experimental design and setup. To prepare the samples, a consistent specimen preparation technique was developed for the cases of dry, barely-to-moderately moist, and highly-to-fully saturated moist soils. On the basis of gathered datasets, empirical correlations for soil thermal conductivity were developed as a function of both temperature and moisture content. The proposed correlations produced excellent fit to majority of the experimental data, and could be easily integrated into numerical analysis of underground heat transfer. As an application example, one of the correlations was employed to evaluate soil thermal conductivity in a numerical study of underground heat loss from a basement wall and floor, in order to illustrate the importance of considering the dependence of soil thermal conductivity on soil texture, temperature and degree of saturation.

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Round-robin measurements of the apparent thermal conductivity of two refractory insulation materials, using high-temperature guarded-hot-plate apparatus

10.6028/nbs.ir.88-3087 ◽

1988 ◽

Cited By ~ 1

Author(s):

Jerome G Hust ◽

David R Smith

Keyword(s):

Thermal Conductivity ◽

High Temperature ◽

Round Robin ◽

Hot Plate ◽

Guarded Hot Plate ◽

Insulation Materials ◽

Apparent Thermal Conductivity ◽

Plate Apparatus

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An automated high-temperature guarded-hot-plate apparatus for measuring apparent thermal conductivity

10.6028/nbs.ir.88-3089 ◽

1988 ◽

Cited By ~ 1

Author(s):

Jerome G Hust ◽

B James Filla ◽

James A Hurley ◽

David R Smith

Keyword(s):

Thermal Conductivity ◽

High Temperature ◽

Hot Plate ◽

Guarded Hot Plate ◽

Apparent Thermal Conductivity ◽

Plate Apparatus

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Development of a single-sided guarded hot plate apparatus for thermal conductivity measurements

Thermal Science ◽

10.2298/tsci151009226t ◽

2016 ◽

Vol 20 (suppl. 1) ◽

pp. 321-329 ◽

Cited By ~ 3

Author(s):

Marijana Terzic ◽

Nenad Milosevic ◽

Nenad Stepanic ◽

Slobodan Petricevic

Keyword(s):

Thermal Conductivity ◽

Fem Analysis ◽

Programming Environment ◽

Conductivity Measurements ◽

Hot Plate ◽

Plate Method ◽

One Dimensional ◽

Guarded Hot Plate ◽

Numerical Heat Transfer ◽

Plate Apparatus

This work presents the development of an experimental setup for measurements on of thermal conductivity of solid materials, such as ceramics, polymers, rubbers, glasses, biological materials, etc. whose thermal conductivity lies in the approximate range between 0.1 and 2 Wm-1K-1. The setup was designed on the principle of the single-sided guarded hot plate method. In order to find the optimal design for generation of traceable one-dimensional heat flux through an investigated 300?300 mm2 specimen, a numerical heat transfer FEM analysis was performed. The principal components of the measuring apparatus, such as hot plate with thermopile, cold plate and auxiliary hot plate were constructed according to the obtained results of simulations. Software for the control of experiment and data acquisition was developed using the LabVIEW programming environment.

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Study on Guarded Hot Plate Apparatus for Measurement of Thermal Conductivity of Small Polymer Specimens

ASME/JSME 2007 Thermal Engineering Heat Transfer Summer Conference, Volume 3 ◽

10.1115/ht2007-32556 ◽

2007 ◽

Cited By ~ 1

Author(s):

Junichi Fujino ◽

Tomohiro Honda

Keyword(s):

Thermal Conductivity ◽

Test Apparatus ◽

Conductivity Data ◽

Hot Plate ◽

Hot Plate Test ◽

Plate Test ◽

Guarded Hot Plate ◽

Experimental Apparatus ◽

Gap Width ◽

Plate Apparatus

The aim of this work is to develop a guarded hot plate test apparatus for measuring the thermal conductivity of polymer specimen, the size of which is smaller and thicker than that recommended by the ISO and JIS. The authors made three experimental apparatus suitable for the different sizes of specimen 50×50, 100×100 and 200×200 mm2 in area, measured the thermal conductivity of polymer as homogeneous materials, which ranged from 0.2 to 0.6 W·m−1·K−1, and carried out the numerical analysis. The uncertainty for the measurement of the thermal conductivity of the polymer specimens is estimated to be within ±4% using our test apparatus. For the test apparatus suitable for the specimen 50×50 mm2, the gap has an effect on the measurement of the thermal conductivity. In addition, the temperature difference ΔTg of the heat source has a direct influence on the deviation in the thermal conductivity data. The influence of the aspect ratio of the specimen and gap width on the measurement is estimated to be within 0.9% for the specimens 50×50 mm2 used in the present study.

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