Top  Previous  Next

VLXE Blend offers the two version of the Sanchez/Lacombe equation of state:

Original Sanchez/Lacombe.

Modified Sanchez/Lacombe


The modified version is obtained by:

Integrating the expression of P from the original

Differentiating with respect to V to get P and mole numbers to get fugacity's


This is not possible with the original version.


Since the modified version obeys an ideal gas limits i.e  P goes to zero if V goes to infinity, it is recommended to use the modified version.


Extensive work has been done in the polymer related field by R. A. Heideman and Ryan Krenz.


Note: For solvents it is possible to obtain the parameters from the critical properties and the acentric factor. This is based on work done made by R. A. Heideman & K. Gauter and is build into the user interface in VLXE Blend.


For more information see the references: 12, 13