Wilke viscosity formula

In the case of viscosity, the semi-empirical formula due to Wilke [432] and modified by Bird et al. [35] can be used. The Wilke formula for mixture viscosity is given by... 

Example 13-3 To demonstrate the use of the predictive method, Example 13-3, which is taken from Ref. 24, is presented. A statement of this example appears in Table 13-4. Physical properties which are listed in the table were estimated as follows. The viscosity of each pure component i in the vapor phase was predicted by use of the correlation proposed by Bird et al.1,2 20 The pure component viscosities so obtained were used to predict the viscosities of the vapor mixtures by use of the semi-empirical formula proposed by Wilke.40... 

The parameter is the viscosity of the mixture, and for gases at moderate pressures (less than 10 atm) it is adequately calculated from the semi-empirical formula of Wilke et al. (Bird et al, 1960)... 

Transport properties such as viscosity and thermal conductivity of a gas mixture are estimated based on the mixture rules. A simplified mixfure model developed based on fhe kinefic theory model is widely used (Bird et. al., 1960 Mills, 2001 Wilke, 1950). These formulae are given as follows ... 

Viscosity is a measure of fluid resisfance to mofion, and if relates fhe strain rate to applied shear stress. A functional dependence of gas viscosify on temperature at low density is given by Chapman-Enskog based on kinetic theory (Bird et al., 1960) using Lennard-Jones potentials. The theory has been also extended to multicomponent gas mixtures. For most common applications, however, a simplified semiempirical formula of Wilke (1950) is used ... 

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