Available mixing rules for liquid surface tension

You can use one of the following mixing rules to calculate the bulk liquid surface tension of a Fluid Type.

Molar Average

where

sm is the surface tension of the mixture

si is the surface tension of pure component i

xi is the molar composition fraction of component i in the liquid phase

This is the default mixing rule.

Logarithmic Molar Average

Power Molar Average

where

r is an exponent that you specify in the Fluid Editor

DIPPR Mixing Rule

where

Vi is the liquid molar volume of pure component i

This mixing rule is the same as the DIST equation from the IK-CAPE thermodynamics package.

MacLeod-Sugden Modified Mixing Rule

References

1. Reid, R. C.; Prausnitz, J. M.; Poling, B. E. The Properties of Gases and Liquids, 4th ed.; McGraw-Hill: New York, 1977; pp. 530–535.