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, GEOS must be built with -DENABLE_PVTPACKAGE=ON (default).

The following attributes are supported:

Name	Type	Default	Description
checkPVTTablesRanges	integer	1	Enable (1) or disable (0) an error when the input pressure or temperature of the PVT tables is out of range.
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	groupName	required	A name is required for any non-unique nodes
phaseNames	groupNameRef_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>