液体纯物质的粘度及扩散系数与蒸发潜热间的关系

本文结合流体的普遍化范德华理论和粘度与扩散系数的自由体积模型,导出了纯物质的液体粘度及分子扩散系数与蒸发潜热间的关系式。对30种纯物质的粘度与蒸发潜热间的关联误差为1.45％;对20种物质的自扩散系数与蒸发潜热间的关联误差为2.9％。所选物系包括强极性、弱极性和非极性分子。本工作为建立传递性质与平衡性质间的关系,以及提出粘度及扩散系数与温度间的新关联式打下了初步基础。

Correlations of Viscosity and Diffusivity for Pure Liquids with Heat of Vaporization

This paper presents a preliminary work on the correlations of transport properties of liquids with equilibrium properties on a theoretical base. Firstly, the correlation of free volumes for vapor and liquid phase in equilibria is derived from the generalized van der Waals theory. Then a fundamental equation which correlates liquid viscosity and diffusivity with heat of vaporization is proposed based on the free volume model for transport properties presented recently. Finally, the working equations for viscosity and dfffusivity is separately derived by use of the modified Chapman-Enskog theroy for the transport properties of vapor phase. The viscosities for 30 substances (417 data points), self--diffusivities for 20 substances (147 data points), including polar and nonpolar, are correlated with heat of vaporization, and the absolute average deviations from experimental data are 1.45 and 2.90 per cent respectively.