Viscosity corresponding states

Calculation of thermophysical properties of gases relies on the principle of corresponding states. Viscosity and conductivity are expressed as the sum of the ideal gas property and a function of the reduced density ... 

Generalized Correlations for Viscosity. Gas viscosity has also been predicted by corresponding states theory (90) using... 

Viscosity. A corresponding states method that requires critical pressure, temperature, and dipole moment has been developed for low pressure gas viscosity (221). This method, which includes a group contribution parameter, is also appHcable to gas mixtures. Whereas a group contribution method is not available for dipole moment, the influence this parameter has can be neglected for many species. 

Utracki,L., Simha,R. Corresponding states relations for the viscosity of moderately concentrated polymer solutions. J. Polymer Sci. Pt. A1,1089-1098 (1963). 

Simha,R., Utracki,L.A. The viscosity of concentrated polymer solutions corresponding states principles. Rheol. Acta 12,455-462 (1973). 

Simha,R., Chan,F.S. Corresponding states relations for the newtonian viscosity of concentrated polynier solutions. Temperature dependence. J. Phys. Chem. 75,256-267... 

For a gas, the effect of pressure on the viscosity depends on the region of P and T of interest relative to the critical point. Near the critical state, the change in viscosity with T at constant pressure can be very large. The correlation of Uyehara and Watson [15] is presented for the reduced viscosity estimated from the corresponding-states method. The critical viscosities of a few gases and liquids are available [15]. These are necessary to calculate the... 

The similarity of this graph to the graph showing the density of a pure substance indicates that the law of corresponding states should hold for viscosity as well as for volumetric behavior. 

The other method has been described by Simha and Utracki in several articles (1963-1973). The method is called a corresponding states principle. A reduced viscosity f/ is plotted against a reduced concentration c, where... 

Unfortunately, there are very few experimental measurements for the viscosity of hydrogen sulfide. A review of the available data is presented in the appendix of this chapter. However, from the few data available and by applying the principle of corresponding states to the viscosity, a chart for the viscosity of H2S was constructed. The resulting plot is shown in figure 2.6. Details of this new correlation are also in the appendix to this chapter. 

Jossi et al. (1962) presented a generalized correlation for the viscosity of high density fluids as a function of the reduced density via a corresponding states method. This method was discussed earlier. Among the gases that Jossi et al. (1962) used to build their correlation were carbon dioxide, methane, ethane, and propane. This gives us some confidence that this approach should be satisfactory for our acid gas mixtures. 

I Onnes<5 found a relation between viscosities in corresponding states for two substances ... 

Herz, Z. andrg. Chem., 1925,147,293 Faust, ibid., 1925, 150,175 Luther, Angew. Chem., 1949, 61, 405 Smoluchowski, Kosmos (Lwow), 1910, 35, 543, concluded that the law of corresponding states does not apply to viscosities. 

If the composition of the gas is known, a more accurate estimate of the gas viscosity can be made by a method proposed by Carr, Kobayashi, and Burrows. The correlating procedure is based on the Law of Corresponding States. Consider the ratio ix/m where p, is the viscosity of the gas at the reduced reservoir temperature and pressure... 

Since this method of estimating gas viscosity is based on the Law of Corresponding States a correction must be applied if the mixture contains appreciable quantities of non-hydrocarbon gases. The corrections which must be added to /t because of the presence of N2, CO2, or H2S in the gas mixtures are shown in the insert plots in Figure 80. Having corrected /ii for the non-hydrocarbon constituents, computation of jj. is carried out in the same manner as before. 

Necessarily chain conformations are reflected in solution properties such as viscosity. In a series of papers Utracki and his colleagues (8-11) have studied Newtonian viscosities of polymer solutions they have also studied polymer melts, and nonpoly-meric liquid phases, organic as well as inorganic ones. The aim of the work was to construct a corresponding states principle for viscosity n in function of temperature T and concentration c. 

Viscosity is a difficult property to predict and flexible predictive models will require further experimental data in order to obtain a better understanding of this property. Many prediction methods are available in literature for the viscosity of pure component and their mixtures [88] most of these are generally based on group contributions (e.g., the Orrick-Erbar method [89], the Sastry-Rao method [90], and the UNIFAC-VISCO method [91]), the corresponding states concept (e.g., Przezdziecki and Sridhar [92], Chatter] ee and Vasant [93], Teja and Rice [94, 95],... 

Teja AS, Rice P (1981) Generalized corresponding states method for the viscosities of liquid-mixtures. Ind Eng Chem Fund 20 77-81... 

Queimada AJ, Rolo LI, Caco AI et al. (2006) Prediction of viscosities and surface tensions of fuels using a new corresponding states model. Fuel 85 874-877... 

Yinghua L, Peisheng M, Ping L (2002) Estimation of liquid viscosity of pure compounds at different temperatures by a corresponding-states group-contribution method. Fluid Phase Equilib 198 123-130... 

Teja and Rice [134] have proposed another relationship to calculate the viscosity of mixtures of polar liquids. It is based on a corresponding states treatment for the mixture compressibility factors. This method is more accurate than the previous one for polar-polar mixtures, particularly for aqueous solutions. It uses two reference-solution models for nonspherical molecules and a single interaction parameter. For methanol-water systems, the accuracy was within 9% [5]. 

Utracki, L.A. Roovers, J.E.L. Viscosity and normal stresses of linear and star branched polystyrene solution. I. Application of corresponding states principle to zero-shear viscosities. Macromolecules 1973, 6 (3), 366-372. 

Krieger and Dougherty applied the theory of corresponding states to obtain the following expression for the viscosity of hard-sphere dispersions ... 

Figure 13.2. Schematic illustration of general form of temperature dependence of zero-shear melt viscosities r o of amorphous polymers. It is seen that r o has a non-Arrhenius universal shape for Tg

At low and moderate pressures, the viscosity of a gas is nearly independent of pressure and can be correlated for engineering purposes as a function of temperatnre only. Eqnations have been proposed based on kinetic theory and on corresponding-states principles these are reviewed in The Properties of Gases and Liquids [15], which also inclndes methods for extending the calculations to higher pressures. Most methods contain molecular parameters that may be fitted to data where available. If data are not available, the parameters can be estimated from better-known quantities such as the critical parameters, acentric factor, and dipole moment. The predictive accuracy for gas viscosities is typically within 5%, at least for the sorts of small- and medinm-sized, mostly organic, molecules used to develop the correlations. 

For high-temperature liquids, compressed gases, and other systems at intermediate densities, a corresponding-states treatment is preferable. The SUPERTRAPP model for thermal conductivity is similar to that described for viscosity in Section 1.5.2, and is available in the same NIST databases [9, 59],... 

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