functionactivityCoefficient_pTN
Information
An activity coefficient is a factor used in thermodynamics to account for deviations from ideal behaviour in a mixture of chemical substances.
It's common to define an activity coefficient for liquid mixtures that can't be described by an equation of state.
Examples of commonly used activity coefficient models are:
- one parameter Margules
- two parameter Margules
- van Laar
- Wilson equation
- NRTL equation
- UNIFAc metjpd
Definition
Activity coefficient gamma is defined by equation:
f_i_liquid=x_i*gamma_i(p,T,x)*f_i_liquid(p,T)
Reference
Chemical and engineering thermodynamics, Stanley I. Sander, 3:rd edition, page 401.
Chemical Engineering Thermodynamics, Pradeep Ahuja, page 453
Inputs
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.SIunits.Pressure | p | Pressure | |
| Modelica.SIunits.Temperature | T | Modelica.SIunits.Temperature | |
| Modelica.SIunits.AmountOfSubstance | N_1ph | Molar substance for the specified phase |
Outputs
| Type | Name | Default | Description |
|---|---|---|---|
| Real[nC] | gamma | Activity coefficients for specified phase |