VISCOSITY - A CRITICAL-REVIEW OF PRACTICAL PREDICTIVE AND CORRELATIVEMETHODS

This paper reviews methods for the prediction and correlation of Newto nian viscosity for pure components and mixtures of dilute gases, dense gases and liquids, focussing on those which are suited for practical engineering use. The methods reviewed were chosen because they are wel l known and accepted or appear potentially promising. They are categor ized as theoretical, semi-theoretical or empirical and further disting uished as predictive or correlative. Brief derivations with relevant e quations and discussions on limitations and reliability of results are presented. In addition, the applicability and average deviations for each method are tabulated, with the recommended methods clearly stated . Furthermore, some gaps in viscosity prediction/correlation are ident ified and promising approaches are discussed.