The effect of molecular shape on dilute gas shear viscosity

Abstract

The relationship between dilute gas shear viscosity and the anisotropy of simple linear molecules has been investigated. A corresponding states comparison of data for spherical and linear molecules, using Boyle properties as reducing parameters, showed some systematic changes of behaviour with increasing elongation of the molecules. These observations were compared with the results of theoretical calculations for the diatomic Lennard-Jones potential using both the classical theory of Taxman and the Monchick-Mason approach. The published calculations based on the Taxman theory were found to be insufficiently precise to show the relatively modest changes seen in the experimental results, and the Monchick-Mason procedure yielded behaviour at low temperatures which differed qualitatively from the experimental values.