Detailed Description

Relative permeability function of the non-wetting phase proposed by Brooks&Corey.

This property must be a medium property, it computes the permeability reduction due to saturation as function of capillary pressure.

Definition at line 25 of file RelPermBrooksCoreyNonwettingPhase.h.

#include <RelPermBrooksCoreyNonwettingPhase.h>

Inheritance diagram for MaterialPropertyLib::RelPermBrooksCoreyNonwettingPhase:

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Collaboration diagram for MaterialPropertyLib::RelPermBrooksCoreyNonwettingPhase:

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Public Member Functions
	RelPermBrooksCoreyNonwettingPhase (std::string name, const double residual_liquid_saturation, const double residual_gas_saturation, const double min_relative_permeability, const double exponent)
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

Private Attributes
const double	residual_liquid_saturation_
const double	residual_gas_saturation_
const double	min_relative_permeability_
const double	exponent_

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

◆ RelPermBrooksCoreyNonwettingPhase()

MaterialPropertyLib::RelPermBrooksCoreyNonwettingPhase::RelPermBrooksCoreyNonwettingPhase	(	std::string	name,
		const double	residual_liquid_saturation,
		const double	residual_gas_saturation,
		const double	min_relative_permeability,
		const double	exponent )

Definition at line 13 of file RelPermBrooksCoreyNonwettingPhase.cpp.

    : residual_liquid_saturation_(residual_liquid_saturation),
      residual_gas_saturation_(residual_gas_saturation),
      min_relative_permeability_(min_relative_permeability),
      exponent_(exponent)
{
    name_ = std::move(name);
 
    if (exponent_ <= 0.)
    {
        OGS_FATAL(
            "RelPermBrooksCoreyNonwettingPhase: exponent 'lambda' must be "
            "positive, but {} was given.",
            exponent_);
    }
    if (residual_liquid_saturation_ < 0.)
    {
        OGS_FATAL(
            "RelPermBrooksCoreyNonwettingPhase: residual_liquid_saturation "
            "must be non-negative, but {} was given.",
            residual_liquid_saturation_);
    }
    if (residual_gas_saturation_ < 0.)
    {
        OGS_FATAL(
            "RelPermBrooksCoreyNonwettingPhase: residual_gas_saturation must "
            "be non-negative, but {} was given.",
            residual_gas_saturation_);
    }
    if (residual_liquid_saturation_ + residual_gas_saturation_ >= 1.)
    {
        OGS_FATAL(
            "RelPermBrooksCoreyNonwettingPhase: residual_liquid_saturation "
            "({}) + residual_gas_saturation ({}) must be less than 1 so that "
            "the effective saturation range is positive.",
            residual_liquid_saturation_, residual_gas_saturation_);
    }
    if (min_relative_permeability_ < 0. || min_relative_permeability_ > 1.)
    {
        OGS_FATAL(
            "RelPermBrooksCoreyNonwettingPhase: min_relative_permeability must "
            "be in [0, 1], but {} was given.",
            min_relative_permeability_);
    }
};

References exponent_, min_relative_permeability_, MaterialPropertyLib::name, MaterialPropertyLib::Property::name_, OGS_FATAL, MaterialPropertyLib::residual_gas_saturation, residual_gas_saturation_, MaterialPropertyLib::residual_liquid_saturation, and residual_liquid_saturation_.

Member Function Documentation

◆ checkScale()

void MaterialPropertyLib::RelPermBrooksCoreyNonwettingPhase::checkScale ( ) const

inlineoverridevirtual

Reimplemented from MaterialPropertyLib::Property.

Definition at line 40 of file RelPermBrooksCoreyNonwettingPhase.h.

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

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

◆ dValue()

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

overridevirtual

This virtual method will compute the property derivative value based on the variables that are passed as arguments with the default implementation using empty variables array for the previous time step.

The default implementation of this method only returns the property value derivative without altering it.

here, an extra computation of saturation is forced, guaranteeing a correct value. In order to speed up the computing time, saturation could be inserted into the primary variable array after it is computed in the FEM assembly.

Reimplemented from MaterialPropertyLib::Property.

Definition at line 104 of file RelPermBrooksCoreyNonwettingPhase.cpp.

{
    if (variable != Variable::liquid_saturation)
    {
        OGS_FATAL(
            "RelPermBrooksCoreyNonwettingPhase::dValue is implemented for "
            "derivatives with respect to liquid saturation only.");
    }
    auto const s_L = std::visit(
        [&variable_array, &pos, t, dt](auto&& scale) -> double
        {
            return scale->property(PropertyType::saturation)
                .template value<double>(variable_array, pos, t, dt);
        },
        scale_);
 
    auto const s_L_res = residual_liquid_saturation_;
    auto const s_L_max = 1. - residual_gas_saturation_;
    auto const lambda = exponent_;
 
    auto const s_eff = (s_L - s_L_res) / (s_L_max - s_L_res);
    // Consistency with value(): at the branch points s_eff == 0 (dry, value
    // clamped to 1.0) and s_eff == 1 (saturated, value clamped to
    // min_relative_permeability) the value is constant, so the derivative is
    // zero.
    if ((s_eff <= 0.) || (s_eff >= 1.))
    {
        return 0.0;
    }
 
    auto const twoL_L = (2. + lambda) / lambda;
    auto const s_eff_pow_twoL_L = std::pow(s_eff, twoL_L);
 
    // Consistency with value(): where the min_relative_permeability clamp is
    // active, the relative permeability is constant and its derivative is
    // zero. Returning the unclamped derivative there would feed the Jacobian
    // a spurious sensitivity over the entire gas-phase invasion band near
    // full saturation (amplified by up to a factor of
    // k_rel/min_relative_permeability in terms scaling with dk_rel/k_rel).
    auto const k_rel_GR = (1. - s_eff) * (1. - s_eff) * (1. - s_eff_pow_twoL_L);
    if (k_rel_GR <= min_relative_permeability_)
    {
        return 0.0;
    }
 
    auto const d_se_d_sL = 1. / (s_L_max - s_L_res);
    auto const dk_rel_GRdse =
        -2. * (1 - s_eff) * (1. - s_eff_pow_twoL_L) -
        twoL_L * std::pow(s_eff, twoL_L - 1.) * (1. - s_eff) * (1. - s_eff);
 
    return dk_rel_GRdse * d_se_d_sL;
}

References exponent_, MaterialPropertyLib::liquid_saturation, min_relative_permeability_, OGS_FATAL, residual_gas_saturation_, residual_liquid_saturation_, MaterialPropertyLib::saturation, MaterialPropertyLib::Property::scale_, and MaterialPropertyLib::Property::value().

◆ value()

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

overridevirtual

Those methods override the base class implementations and actually compute and set the property values_ and dValues_.

here, an extra computation of saturation is forced, guaranteeing a correct value. In order to speed up the computing time, saturation could be inserted into the primary variable array after it is computed in the FEM assembly.

Reimplemented from MaterialPropertyLib::Property.

Definition at line 64 of file RelPermBrooksCoreyNonwettingPhase.cpp.

{
    auto const s_L = std::visit(
        [&variable_array, &pos, t, dt](auto&& scale) -> double
        {
            return scale->property(PropertyType::saturation)
                .template value<double>(variable_array, pos, t, dt);
        },
        scale_);
 
    auto const s_L_res = residual_liquid_saturation_;
    auto const s_L_max = 1. - residual_gas_saturation_;
 
    auto const lambda = exponent_;
 
    auto const s_eff = (s_L - s_L_res) / (s_L_max - s_L_res);
 
    if (s_eff >= 1.0)
    {
        // fully saturated medium
        return min_relative_permeability_;
    }
    if (s_eff <= 0.0)
    {
        // dry medium
        return 1.0;
    }
 
    auto const k_rel_GR = (1. - s_eff) * (1. - s_eff) *
                          (1. - std::pow(s_eff, (2. + lambda) / lambda));
 
    return std::max(k_rel_GR, min_relative_permeability_);
}