Compositional multiphase fluid model

Overview

This model represents a full composition description of a multiphase multicomponent fluid. Phase behavior is modeled by an Equation of State (EOS) and partitioning of components into phases is computed based on instantaneous chemical equilibrium via a two- or three-phase flash. Each component (species) is characterized by molar weight and critical properties that serve as input parameters for the EOS. See Petrowiki for more information.

Parameters

The model represented by <CompositionalMultiphaseFluid> node in the input. Under the hood this is a wrapper around PVTPackage library, which is included as a submodule. In order to use the model, GEOSX must be built with -DENABLE_PVTPACKAGE=ON (default).

The following attributes are supported:

Name	Type	Default	Description
componentAcentricFactor	real64_array	required	Component acentric factors
componentBinaryCoeff	real64_array2d	{{0}}	Table of binary interaction coefficients
componentCriticalPressure	real64_array	required	Component critical pressures
componentCriticalTemperature	real64_array	required	Component critical temperatures
componentMolarWeight	real64_array	required	Component molar weights
componentNames	string_array	required	List of component names
componentVolumeShift	real64_array	{0}	Component volume shifts
equationsOfState	string_array	required	List of equation of state types for each phase
name	string	required	A name is required for any non-unique nodes
phaseNames	string_array	required	List of fluid phases

Supported phase names are:

Value	Comment
oil	Oil phase
gas	Gas phase
water	Water phase

Supported Equation of State types:

Value	Comment
PR	Peng-Robinson EOS
SRK	Soave-Redlich-Kwong EOS

Example

<Constitutive>
  <CompositionalMultiphaseFluid name="fluid1"
                                phaseNames="{ oil, gas }"
                                equationsOfState="{ PR, PR }"
                                componentNames="{ N2, C10, C20, H2O }"
                                componentCriticalPressure="{ 34e5, 25.3e5, 14.6e5, 220.5e5 }"
                                componentCriticalTemperature="{ 126.2, 622.0, 782.0, 647.0 }"
                                componentAcentricFactor="{ 0.04, 0.443, 0.816, 0.344 }"
                                componentMolarWeight="{ 28e-3, 134e-3, 275e-3, 18e-3 }"
                                componentVolumeShift="{ 0, 0, 0, 0 }"
                                componentBinaryCoeff="{ { 0, 0, 0, 0 },
                                                      { 0, 0, 0, 0 },
                                                      { 0, 0, 0, 0 },
                                                      { 0, 0, 0, 0 } }"/>
</Constitutive>