Aspen Physical Property System - Physical Property Models

Redlich-Kwong-Soave-MHV2
This equation-of-state model uses the Redlich-Kwong-Soave equation-of-state
for pure compounds. The predictive MHV2 mixing rules are used. Several
alpha functions can be used in the RK-Soave-MHV2 equation-of-state model
for a more accurate description of the pure component behavior. The pure
component behavior and its parameter requirements are described in
Standard Redlich-Kwong-Soave, and in Soave Alpha Functions.
Note: You can choose any of the available alpha functions, but you cannot
define multiple property methods based on this model using different alpha
functions within the same run.
The MHV2 mixing rules are an example of modified Huron-Vidal mixing rules.
A brief introduction is provided in Huron-Vidal Mixing Rules. For more details,
see MHV2 Mixing Rules.
Schwartzentruber-Renon
The Schwartzentruber-Renon equation-of-state is the basis for the SR-POLAR
property method. It can be used to model chemically nonideal systems with
the same accuracy as activity coefficient property methods, such as the
WILSON property method. This equation-of-state is recommended for highly
non-ideal systems at high temperatures and pressures, such as in methanol
synthesis and supercritical extraction applications.
The equation for the model is:
p =
Where:
a =
b =
c =
ai
bi
ci
ka,ij
lij
=
=
=
=
=
2 Thermodynamic Property Models 57
(for T < Tci)