Abstract
Most researchers do not correct thermophysical property data published in the literature for thermal expansion effects. Even values reported by the National Bureau of Standards for standard reference materials (SRM’s) are not corrected for dimensional changes. Users of the data and, in fact, many researchers assume that corrections have been made or that they are negligible compared to experimental errors. However, the corrections may be several times larger than they are assumed to be because customary thinking concerning dimensional correction is based on the units of the thermophysical properties. The present paper shows that there is not necessarily a one-to-one relation between the expansion correction and the power to which length enters into the property units. In the case of thermal conductivity “λ” for example, the units are often expressed as W cm-1 K-1 and one might think that λcorrected=(1+Δ L/L0)-1 λuncorrected. Actually the correction term may be (1+Δ L/L0)-n where n=0, 1, 2 or 3 depending upon the experimental technique used — or the correction term may even be based on the expansion of a material other than the sample. Similarly the hemispherical total emittance (a dimensionless quantity) may require a (1+Δ L/L0)-2 correction term. Thus the units of the property involved do not necessarily provide a good guide to the correction term.
Basically one must correct each experimentally measured value for dimensional changes rather than merely using property units and correcting the final value. Also in the case of anisotropic materials, one must use the appropriate values of expansion for the directions in question. In this case λ is W cm cm-2 K-1 and not W cm-1 K-1.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
R. E. Taylor and J. Morreale, “Thermal Conductivity of Titanium Carbide, Zirconium Carbide, and Titanium Nitrite at High Temperatures,” J. Am. Ceram. Soc. 47[2] pp. 69–73, 1964.
N. S. Rasor and J. D. McClelland, “Thermal Property Measurements at Very High Temperatures,” Rev. Sci. Inst. 31 [6] pp. 595–604, 1960.
R. E. Taylor, F. E. Davis, and R. W. Powell, “Direct Heating Methods for Measuring Thermal Conductivity of Solids at High Temperatures,” High Temp. — High Pressures 1 pp. 663–673, 1969.
R. E. Taylor, “Survey on Direct Heating Methods for High-Temperature Thermophysical Property Measurements of Solids,” High Temp. — High Pressures 4 pp. 523–531, 1972.
R. E. Taylor, “Thermal Properties of Tungsten SRM’s 730 and 799” (submitted for publication, Journal of Heat Transfer).
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 1978 Purdue Research Foundation
About this chapter
Cite this chapter
Taylor, R.E. (1978). On Correcting Thermophysical Property Data for Thermal Expansion Effects. In: Mirkovich, V.V. (eds) Thermal Conductivity 15. Springer, Boston, MA. https://doi.org/10.1007/978-1-4615-9083-5_22
Download citation
DOI: https://doi.org/10.1007/978-1-4615-9083-5_22
Publisher Name: Springer, Boston, MA
Print ISBN: 978-1-4615-9085-9
Online ISBN: 978-1-4615-9083-5
eBook Packages: Springer Book Archive