LIQUID DYNAMIC VISCOSITY - A GENERAL PREDICTION METHOD WITH APPLICATION TO REFRIGERANTS AND REFRIGERANT MIXTURES

This paper discusses prediction methods which are able to provide the dynamic viscosity, μ, of liquids along the saturation line. The best empirical or semi-empirical correlations existing in the literature are critically presented and checked to outline the usefulness of the new prediction method presented in this paper. Fifty substances (organic compounds, inorganic compounds and pure elements) are examined to show the reliability of the new simple equation which contains three factors (A, B and C) related to the molecular structure and the most important physical properties. The general scheme of prediction is then applied to the particular case of refrigerant fluids belonging to the methane and ethane families and to their binary mixtures. The accuracy of the proposed prediction method is checked using the most recent and reliable experimental dynamic viscosity data available in literature, and the mean and the maximum deviations between predicted and experimental μ values are shown to be less than 3 and 8%, respectively. © 1990.