BIBLIOS

Document type
Journal articles

Document subtype
Full paper

Title
An apparatus to measure the thermal conductivity of liquids

Participants in the publication
C A Nieto de Castro (Author)
Dep. Química e Bioquímica
CQE
J C G Calado (Author)
INSTITUTO SUPERIOR TÉCNICO
W A Wakeham (Author)
IMPERIAL COLLEGE LONDON
M Dix (Author)
IMPERIAL COLLEGE LONDON

Summary
The paper describes an apparatus for the\nmeasurement of the thermal conductivity of non-conducting\nliquids under their saturation vapour pressure. The\ninstrument, which is based upon the transient hot wire\nprinciple, has been designed so that the measuring element\nconforms as closely as possible to an infinite line source of\nheat in an infinite fluid. Under these conditions the thermal\nconductivity of the liquid can be determined from the slope\nof a plot of the temperature rise of the heating element\nagainst the logarithm of time. The measurement system has\nbeen arranged so as to provide as many as 60 points on this\nplot for any particular thermodynamic state of the fluid\nunder investigation. The reproducibility of the instrument is\nof the order of 0.03 % and the precision of the measurements\nis estimated as k 0.1 %. Owing to a lack of a suitable theory\nfor the effects of radiative heat transfer, the accuracy of the\nthermal conductivity values cannot be defined unequivocally,\nbut a reasoned upper bound is k 0.3 %. Preliminary results\nare presented for n-heptane at three temperatures in the\nrange 20 to 30°C.


Institution
INSTITUTO SUPERIOR TÉCNICO

Where published
Journal of Physics E: Scientific Instruments

Publication Identifiers

Publisher
IOP Publishing



Document Identifiers
DOI - https://doi.org/10.1088/0022-3735/9/12/020
URL - http://dx.doi.org/10.1088/0022-3735/9/12/020

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