Thermal conductivity of diatomic gases: Liquid and gaseous states

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 TR 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*,, 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, = 8.55 X cal./sec. cm. OK. for nitrogen was used, an extensive reduced thermalconductivity 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.Present technoiogical advances continue to depend upon progress in understanding the fundamentals of mass and energy transfer; consequently, more careful scrutiny of these operations has stimulated an increasing interest in transport properties. An accurate but simple means of predicting coefficients of diffusion, thermal conductivity, and viscosity is needed to meet the demands of 40.

The Viscosity and Thermal Conductivity Coefficients of Gaseous and Liquid Fluorine

“…We think it necessary to comment on the law of corresponding states which is a convenient correlating tool for many properties of fluids and obviousl y comes to mind in our case: it would be quite straightforward if one could obtain the transport properties of fluorine given the properties of another fluid. In fact, this approach has been followed in the past [9,16,17]. Unfortunately, we can demonstrate that it does not work very well.…”

“…Equations (16) and (19) also allow x to be found for inclusion in equation (15). We have determined MET transport coefficients for many fluids from the appropriate equations of state and intermolecular potential functions [6J.…”

Molecular effects in heat conduction through porous rocks

“…082; the value at atmospheric pressure is 0.063 mcal/cm sec øC[Schaefer and Thodos, 1959]. This increase in the conductivity of the saturant corresponds to an increase of only 0.15 mcal/cm sec øC in the effective conductivity of Berea(Fig.…”

The transport properties of carbon dioxide

“…Viscosities and thermal conductivities calculated with Equations (4) and (5) have been found to be pressure insensitive from 5 mm. of mercury (4,45) up to 10 atm. On the other hand Equation (6) indicates that the self-diffusivity is inversely proportional to pressure for these moderate pressure conditions.…”