Abo Bibliothek: Guest

ISSN Online: 2377-424X

ISBN Print: 978-1-56700-474-8

ISBN Online: 978-1-56700-473-1

International Heat Transfer Conference 16
August, 10-15, 2018, Beijing, China

ADVANCES IN MEASURING THERMOPHYSICAL PROPERTIES OF LIQUIDS BY THE TRANSIENT PLANE SOURCE TECHNIQUE

Get access (open in a dialog) DOI: 10.1615/IHTC16.tpm.023089
pages 8727-8734

Abstrakt

Thermophysical properties of deionized water, toluene (Pr ≈ 7) and polyglycol DME250 (Pr ≈ 90) were measured by the transient plane source (TPS) technique at 293K to test the limitations of the TPS system. In contrast to earlier studies of other authors, the results of the preliminary measurements show the suitability of the TPS-method for determining both the thermal conductivity and the thermal diffusivity of liquids with deviations ≤ 2.1% from the reference liquid using a given volumetric heat capacity. Interestingly, it can be stated that the characteristic time as an important parameter is much below the known limits for a reliable measurement. Moreover, a special designed measurement cell equipped with a defined open-cell solid matrix to delay or even avoid the onset of convection is presented. In contrast to the direct TPS measurement in liquids, results of the effective thermal conductivity of a two-phase system (liquid and open-cell solid matrix) show no influence of convection anymore. Also, models known from literature, which are used to recalculate the thermal conductivity of water from the measured effective value, are presented. The resulting liquid properties are in good agreement with reference data.