Thermal conductivity of diatomic gases: Liquid and gaseous states

✍ Scribed by Charles A. Schaefer; George Thodos

• Publisher: American Institute of Chemical Engineers
• Year: 1959
• Tongue: English
• Weight: 732 KB
• Volume: 5
• Category: Article
• ISSN: 0001-1541
• DOI: 10.1002/aic.690050322

✦ Synopsis

Abstract

After an extensive literature survey the experimental thermal‐conductivity data for twelve diatomic gases were utilized to produce an accurate and expedient means of predicting values over extensive ranges of temperature and pressure. Plotting values of k* against T~R~ on logarithmic coordinates produced similarities pointing to the existence of corresponding states behavior for this family of substances with the exception of hydrogen. Because hydrogen cannot be included in a correlation generalized for the diatomic gases, it has been eliminated from this study. Based on atmospheric pressure data, ratios of k*/k*~T~~c~ produced a unique relationship with reduced temperature. To include the effect of pressure, residual thermal conductivities were correlated with density for nitrogen and oxygen, the only substances for which high‐pressure data exist. These relationships enabled the determination of the thermal conductivity at the critical point. When the value k~c~ = 8.55 × 10^−5^ cal./sec. cm. °K. for nitrogen was used, au extensive reduced thermal‐conductivity correlation was constructed against reduced temperature for parameters of constant reduced pressure. This chart, extending to reduced pressures of 100 and to reduced temperatures of 85, is recommended for the diatomic gases in their gaseous and liquid states.

The developed correlation reproduces experimental nitrogen data to within 1.39%. For the other diatomic gases experimental agreement extends from 1.00 to 3.20%. Such agreement indicates that this correlation is more reliable for the diatomic gases than are other generalized plots presented in the literature.