This method (SRKS) uses a new mixing rule to eliminate the flaw in the original Panagiotopoulos-Reid mixing rule. Four adjustable parameters are used, with the mixing rule designed to produce good results for mixtures of polar and nonpolar compounds.
The SRKS method in PRO/II uses an improved alpha correlation developed by SimSci. The improved correlation provides more accurate vapor pressure predictions than the original SRK formulation for a wide variety of components.
In addition to K-values, the SRKS equation may be used to predict the enthalpies, entropies and densities for the liquid and vapor phases. The predicted liquid phase densities are not very accurate and the API method is selected by default when this system is chosen.
Refer "Soave-Redlich-Kwong SimSci (SRKS)" under "Equations of State" in Chapter 2, Volume 1 of the PRO/II Reference Manual for more information.
Application Guidelines
Same as those for SRK-Modified Panagiotopoulos-Reid method.