MaterialPropertyLib::WaterVapourDensity Class Reference

Detailed Description

A model for water vapour density in the unsaturated porous media.

The water vapour density is given by

\[ \rho_v = h\, \rho_{vS}, \]

where \(h\) is the relative humidity according to

\[ h=\exp({\frac{p}{\rho_w R T}}), \]

with \(R\) the specific gas constant for water vapour, and \(\rho_{vS}\), is the saturated vapour density given by

\[ \rho_{vS}=10^{-3}\, \exp({19.819-4975.9/T}). \]

The specific gas constant for water vapour \(R=461.6\,\text{J}\,\text{kg}^{-1}\text{K}^{-1}\), the value is calculated by \(R_g/M_w\) with \(R_g= 8.3144621\,\text{J}\,\text{mol}^{-1}\text{K}^{-1}\), the ideal gas constant, and \(M_w=0.018016\,\text{kg}\,\text{mol}^{-1}\), the molar mass of water.

The formula of this density model is presented on page 20 of [20].

In the application, the vapour density related terms in the mass balance equation are multiplied with \(1-S\) with \( S \), the water saturation. Therefore the application of the water vapour density model is naturally restricted in the unsaturated zones.

Definition at line 53 of file WaterVapourDensity.h.

#include <WaterVapourDensity.h>

Inheritance diagram for MaterialPropertyLib::WaterVapourDensity:

Collaboration diagram for MaterialPropertyLib::WaterVapourDensity:

Public Member Functions
	WaterVapourDensity (std::string name)
void	checkScale () const override
PropertyDataType	value (VariableArray const &variable_array, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const override
PropertyDataType	dValue (VariableArray const &variable_array, Variable const variable, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const override
Public Member Functions inherited from MaterialPropertyLib::Property
virtual	~Property ()
virtual PropertyDataType	initialValue (ParameterLib::SpatialPosition const &pos, double const t) const
virtual PropertyDataType	value () const
virtual PropertyDataType	value (VariableArray const &variable_array, VariableArray const &variable_array_prev, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const
virtual PropertyDataType	dValue (VariableArray const &variable_array, VariableArray const &variable_array_prev, Variable const variable, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const
virtual PropertyDataType	d2Value (VariableArray const &variable_array, Variable const variable1, Variable const variable2, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const
	Default implementation: 2nd derivative of any constant property is zero.
virtual void	setProperties (std::vector< std::unique_ptr< Phase > > const &phases)
	Default implementation:
void	setScale (std::variant< Medium *, Phase *, Component * > scale)
template<typename T >
T	initialValue (ParameterLib::SpatialPosition const &pos, double const t) const
template<typename T >
T	value () const
template<typename T >
T	value (VariableArray const &variable_array, VariableArray const &variable_array_prev, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const
template<typename T >
T	value (VariableArray const &variable_array, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const
template<typename T >
T	dValue (VariableArray const &variable_array, VariableArray const &variable_array_prev, Variable const variable, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const
template<typename T >
T	dValue (VariableArray const &variable_array, Variable const variable, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const
template<typename T >
T	d2Value (VariableArray const &variable_array, Variable const &variable1, Variable const &variable2, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const

Additional Inherited Members
Protected Attributes inherited from MaterialPropertyLib::Property
std::string	name_
PropertyDataType	value_
	The single value of a property.
PropertyDataType	dvalue_
std::variant< Medium *, Phase *, Component * >	scale_

Constructor & Destructor Documentation

WaterVapourDensity()

MaterialPropertyLib::WaterVapourDensity::WaterVapourDensity ( std::string name )

inlineexplicit

Definition at line 56 of file WaterVapourDensity.h.

{ name_ = std::move(name); }

References MaterialPropertyLib::name, and MaterialPropertyLib::Property::name_.

Member Function Documentation

checkScale()

void MaterialPropertyLib::WaterVapourDensity::checkScale ( ) const

inlineoverridevirtual

Reimplemented from MaterialPropertyLib::Property.

Definition at line 57 of file WaterVapourDensity.h.

    {
        if (!std::holds_alternative<Phase*>(scale_))
        {
            OGS_FATAL(
                "The property 'WaterVapourDensity' is "
                "implemented on the 'Phase' scale only.");
        }
    }

References OGS_FATAL, and MaterialPropertyLib::Property::scale_.

dValue()

PropertyDataType MaterialPropertyLib::WaterVapourDensity::dValue ( VariableArray const & variable_array, Variable const variable, ParameterLib::SpatialPosition const & pos, double const t, double const dt ) const

overridevirtual

Returns

The derivative of water vapour density with respect to temperature or phase (water) pressure.

Reimplemented from MaterialPropertyLib::Property.

Definition at line 54 of file WaterVapourDensity.cpp.

{
    double const p = variable_array.liquid_phase_pressure;
    double const T = variable_array.temperature;
    double const water_density = variable_array.density;
 
    if (variable == Variable::temperature)
    {
        double const h = humidity(T, p, water_density);
        double const rho_v = h * saturatedVaporDensity(T);
        double const drho_vS_dT = dsaturatedVaporDensitydT(T);
 
        return h * drho_vS_dT - rho_v * p /
                                    (water_density * T * T *
                                     MaterialLib::PhysicalConstant::
                                         SpecificGasConstant::WaterVapour);
    }
 
    if (variable == Variable::liquid_phase_pressure)
    {
        double const factor =
            1.0 /
            (MaterialLib::PhysicalConstant::SpecificGasConstant::WaterVapour *
             T * water_density);
        double const dhumiditydp = factor * std::exp(factor * p);
 
        return dhumiditydp * saturatedVaporDensity(T);
    }
 
    OGS_FATAL(
        "WaterVapourDensity::dValue is implemented for derivatives with "
        "respect to temperature or liquid_phase_pressure only.");
}

References MaterialPropertyLib::VariableArray::density, MaterialPropertyLib::dsaturatedVaporDensitydT(), MaterialPropertyLib::humidity(), MaterialPropertyLib::liquid_phase_pressure, MaterialPropertyLib::VariableArray::liquid_phase_pressure, OGS_FATAL, MaterialPropertyLib::saturatedVaporDensity(), MaterialPropertyLib::temperature, MaterialPropertyLib::VariableArray::temperature, and MaterialLib::PhysicalConstant::SpecificGasConstant::WaterVapour.

value()

PropertyDataType MaterialPropertyLib::WaterVapourDensity::value ( VariableArray const & variable_array, ParameterLib::SpatialPosition const & pos, double const t, double const dt ) const

overridevirtual

Returns

The water vapour density.

Reimplemented from MaterialPropertyLib::Property.

Definition at line 42 of file WaterVapourDensity.cpp.

{
    double const p = variable_array.liquid_phase_pressure;
    double const T = variable_array.temperature;
    double const water_density = variable_array.density;
 
    return humidity(T, p, water_density) * saturatedVaporDensity(T);
}

References MaterialPropertyLib::VariableArray::density, MaterialPropertyLib::humidity(), MaterialPropertyLib::VariableArray::liquid_phase_pressure, MaterialPropertyLib::saturatedVaporDensity(), and MaterialPropertyLib::VariableArray::temperature.

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The documentation for this class was generated from the following files:

• MaterialLib/MPL/Properties/Density/WaterVapourDensity.h
• MaterialLib/MPL/Properties/Density/WaterVapourDensity.cpp