Viscosity Versus Pressure, Temperature and Composition of the Ternary System Heptane + Methylcyclohexane + 1-Methylnaphtalene. Comparative Analysis of Some Models

Abstract

This paper reports results concerning the dynamic viscosity n of three pure substances (heptane, methylcyclohexane, and 1-methylnaphtalene), their three associated binaries and the ternary as a function of pressure (up to 100 MPa), temperature (303.15, 323.15, and 343.15 K) and molar fraction. All our previously published experimental values (810 points) have been used in order to test several representative models of the dynamic viscosity, such as a self-referencing model, a model based on the corresponding state concept, a model based on the hard sphere theory, a model based on residual viscosity, mixing laws and the coupling of these mixing laws with the self-referencing model. an intrinsic inefficiency of the models involving one or more adjustable parameters have been shown. Good performances given by coupling the self referencing model with the Grunberg and Nissan mixing rule, properly modified, have been emphasised, as the absolute average deviation (1.97%) is of the magnitude of the experimental uncertainty. Similar results have been highlighted with the model derived from the hard sphere theory (Dymond - Assael equation).

Key Words:

• Viscosity
• hydrocarbons
• ternary
• high pressure
• models