Kinematic viscosities and densities of eight binary and four ternary liquid mixtures of polar components are reported for various temperatures. Experimental viscosities were correlated with McAMster's equation of viscosity and with a modified form of the McAllister equation.

Klnematlc vlscosltles of eight blnary, five ternary, and one quaternary llquld mlxtures are reported for a wide range of temperatures and composltlon. The data were correlated wlth the McAlllster equation and also wlth two modified verslons of the McAllister equation. I ntroductlonThe solution to many engineering problems involving heat transfer, mass transfer, and fluid flow requires quantitative information on the viscosities of pure liquids or liquid mixtures.In the present work, kinematic viscosities of eight binary, five ternary, and one quaternary liquid mixtures containing strongly polar components, including water, are presented. For comparison, the viscosity data were correlated by means of the methods of Soliman ( 7 ) , McAllister (2), and Dizechi (3). Experlmental SectlonKinematic viscosities were measured with a Schott automated viscosity measuring system. This system consists of a basic control unit including a printer, a measuring stand, a constant-temperature-bath circulator, and calibrated capillary viscometers, depending on the measuring range. The capillary viscometers were calibrated by Schott Glaswerke, Mainz, FRG. The calibration was checked with distilled water and was found to produce measured values that agreed with published data within 0.4%. For instance, the "accepted" value of the viscosity of water at 25 O C is v = 0.8929 X lo-' m2/s, while the value obtained with the Schott automated viscosity measuring system is v = 0.8950 X lo-' m2/s. Thus the deviation of the measured value from the standard value is less than 0.3%. For measurements at and below ambient temperature, this system was used in conjunction with a Model RTE-4 Neslab cooling system. Bath temperatures can be set and held constant to about fO.0; O C . Time measurements were made automatically with the help of a quartz timer with a resolution of 0.01 s and two light barriers across the viscometer. The light barriers detect the passing meniscus of the studied fluid and provide the start-stop signals for the time measurement. In any series of experiments at identical conditions, the deviation of measured values from the "average" value was found to be smaller than 0.5 YO.Liquid mixtures were prepared with a Mettler precision digital balance Model PE 400 with an accuracy of *lo-* g. The buoyancy effect was neglected, since errors in measured mass fractions introduced by this effect were much smaller than 0.1 % . Fluids used in this work were all purified, Spector AR.Evaporation rates were negligible in transferring the mixtures into capillary viscometers. Results and DlscussionViscosities of the following mixtures were measured at different temperatures, and the resutts of these measurements are listed in Table I: 2-propanol-water mixtures at 25 O C , 1-propanol-water mixtures at 25 OC; methanol-water mixtures at 25 O C , ethanol-water mixtures at 25 OC; ethanol-methanol mixtures at 25 OC; 2-propanol-1-propanol mixtures at 10, 20, 376 30, 40, and 50 O C ; 2-propanol-methanol mix:ures at 10, 20, 30, 40, and 50 OC; 2-propanol-et...

A predictive theory for condensation of a binary mixture on a cooled vertical plate has been formulated on the basis of the conservation laws and other fundamental physical principles. The formulation involves the analysis of the transport processes in the condensate film and in the vapor boundary layer, along with conditions of continuity, conservation, and equilibrium at the liquid-vapor interface. The analytical method is applied to the condensation of saturated binary mixtures of methanol and water vapor, and heat transfer results are obtained for a range of operating conditions. For large condensation rates, the heat transfer can be calculated by a simplified method which bypasses the detailed analysis of the vapor boundary layer.

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