activity_coefficients

class thermosteam.equilibrium.activity_coefficients.ActivityCoefficients

Abstract class for the estimation of activity coefficients. Non-abstract subclasses should implement the following methods:

__init__(self, chemicals: Iterable[Chemicals]):

Should use pure component data from chemicals to setup future calculations of activity coefficients.

__call__(self, x: 1d array, T: float):

Should accept an array of liquid molar compositions x, and temperature T (in Kelvin), and return an array of activity coefficients. Note that the molar compositions must be in the same order as the chemicals defined when creating the ActivityCoefficients object.

property chemicals

tuple[Chemical] All chemicals involved in the calculation of activity coefficients.

class thermosteam.equilibrium.activity_coefficients.IdealActivityCoefficients(chemicals)

Create an IdealActivityCoefficients object that estimates all activity coefficients to be 1 when called with a composition and a temperature (K).

Parameters

chemicals (Iterable[Chemical]) –

__call__(xs, T)

Call self as a function.

class thermosteam.equilibrium.activity_coefficients.GroupActivityCoefficients

Abstract class for the estimation of activity coefficients using group contribution methods.

Parameters

chemicals (Iterable[Chemical]) –

__call__(x, T)

Return UNIFAC coefficients.

Parameters

• x (array_like) – Molar fractions

• T (float) – Temperature (K)

class thermosteam.equilibrium.activity_coefficients.UNIFACActivityCoefficients

Create a UNIFACActivityCoefficients that estimates activity coefficients using the UNIFAC group contribution method when called with a composition and a temperature (K).

Parameters

chemicals (Iterable[Chemical]) –

class thermosteam.equilibrium.activity_coefficients.DortmundActivityCoefficients

Create a DortmundActivityCoefficients that estimates activity coefficients using the Dortmund UNIFAC group contribution method when called with a composition and a temperature (K).

Parameters

chemicals (Iterable[Chemical]) –