Cubic equations of state for transport properties

Abstract

A method is presented for the prediction of the background contribution of residual thermal conductivities and residual viscosities of nonpolar or slightly polar substances. The method is based on the concept of transport equations of state describing the transport properties in terms of pressure and temperature by pressure explicit equations similar to thermal equations of state. The transport equation of state is derived from a generalized cubic thermal equation of state and a universal function for the density dependence of the residual part of the transport properties. A comparison of calculated and recommended values of the thermal conductivity of 35 and the viscosity of 23 substances yields an absolute average deviation of 6% for the thermal conductivity and of 5% for the viscosity. The Maxwell condition is applied to the generalized transport equation of state to predict consistently the transport properties along the vapor-liquid coexistence curve.