Material to calculate van Genuchten-type relative permeability of an arbitrary phase given the saturation and exponent of that phase. More...

#include <PorousFlowRelativePermeabilityVG.h>

Inheritance diagram for PorousFlowRelativePermeabilityVG:

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Public Member Functions
	PorousFlowRelativePermeabilityVG (const InputParameters &parameters)

Protected Member Functions
virtual Real	relativePermeability (Real seff) const override
	Relative permeability equation (must be overriden in derived class) More...

virtual Real	dRelativePermeability (Real seff) const override
	Derivative of relative permeability with respect to effective saturation. More...

virtual void	computeQpProperties () override

virtual Real	effectiveSaturation (Real saturation) const
	Effective saturation of fluid phase. More...

Protected Attributes
const Real	_m
	van Genuchten exponent m for the specified phase More...

const bool	_wetting
	Whether to use the wetting or non-wetting van Genuchten expression. More...

const Real	_cut
	Start of cubic smoothing. More...

const Real	_cub0
	Parameter of the cubic. More...

const Real	_cub1
	Parameter of the cubic. More...

const Real	_cub2
	Parameter of the cubic. More...

const Real	_cub3
	Parameter of the cubic. More...

const Real	_scaling
	Relative permeability is multiplied by this quantity. More...

const MaterialProperty< std::vector< Real > > &	_saturation
	Saturation material property. More...

MaterialProperty< Real > &	_relative_permeability
	Relative permeability material property. More...

MaterialProperty< Real > &	_drelative_permeability_ds
	Derivative of relative permeability wrt phase saturation. More...

const Real	_s_res
	Residual saturation of specified phase. More...

const Real	_sum_s_res
	Sum of residual saturations over all phases. More...

const Real	_dseff_ds
	Derivative of effective saturation with respect to saturation. More...

const unsigned int	_phase_num
	Phase number of fluid. More...

const std::string	_phase
	Stringified fluid phase number. More...

Detailed Description

Material to calculate van Genuchten-type relative permeability of an arbitrary phase given the saturation and exponent of that phase.

From van Genuchten, M. Th., A closed for equation for predicting the hydraulic conductivity of unsaturated soils, Soil Sci. Soc., 44, 892-898 (1980)

Optionally this relative permeability may be smoothed with a cubic near seff=1 The relative permeability is a cubic for seff>_cut. The cubic is chosen so that the derivative is zero for seff=1, and that the derivative and value matches the van Genuchten expression for seff=_cut.

Definition at line 32 of file PorousFlowRelativePermeabilityVG.h.

Constructor & Destructor Documentation

◆ PorousFlowRelativePermeabilityVG()

PorousFlowRelativePermeabilityVG::PorousFlowRelativePermeabilityVG ( const InputParameters & parameters )

Definition at line 40 of file PorousFlowRelativePermeabilityVG.C.

   : PorousFlowRelativePermeabilityBase(parameters),
     _m(getParam<Real>("m")),
     _wetting(getParam<bool>("wetting")),
     _cut(getParam<Real>("seff_turnover")),
     _cub0(_wetting ? PorousFlowVanGenuchten::relativePermeability(_cut, _m)
                    : PorousFlowVanGenuchten::relativePermeabilityNW(_cut, _m)),
     _cub1(_wetting ? PorousFlowVanGenuchten::dRelativePermeability(_cut, _m)
                    : PorousFlowVanGenuchten::dRelativePermeabilityNW(_cut, _m)),
     _cub2(_cut < 1.0
               ? (getParam<bool>("zero_derivative")
                      ? 3.0 * (1.0 - _cub0 - _cub1 * (1.0 - _cut)) / Utility::pow<2>(1.0 - _cut) +
                            _cub1 / (1.0 - _cut)
                      : (_wetting ? PorousFlowVanGenuchten::d2RelativePermeability(_cut, _m)
                                  : PorousFlowVanGenuchten::d2RelativePermeabilityNW(_cut, _m)))
               : 0.0),
     _cub3(_cut < 1.0
               ? (getParam<bool>("zero_derivative")
                      ? -2.0 * (1.0 - _cub0 - _cub1 * (1.0 - _cut)) / Utility::pow<3>(1.0 - _cut) -
                            _cub1 / Utility::pow<2>(1.0 - _cut)
                      : (1.0 - _cub0 - _cub1 * (1.0 - _cut) - _cub2 * Utility::pow<2>(1.0 - _cut)) /
                            Utility::pow<3>(1.0 - _cut))
               : 0.0)
 {
 }

Member Function Documentation

◆ computeQpProperties()

void PorousFlowRelativePermeabilityBase::computeQpProperties ( )

overrideprotectedvirtualinherited

Definition at line 59 of file PorousFlowRelativePermeabilityBase.C.

 {
   // Effective saturation
   Real seff = effectiveSaturation(_saturation[_qp][_phase_num]);
   Real relperm, drelperm;
  
   if (seff < 0.0)
   {
     // Relative permeability is 0 for saturation less than residual
     relperm = 0.0;
     drelperm = 0.0;
   }
   else if (seff >= 0.0 && seff <= 1)
   {
     relperm = relativePermeability(seff);
     drelperm = dRelativePermeability(seff);
   }
   else // seff > 1
   {
     // Relative permeability is 1 when fully saturated
     relperm = 1.0;
     drelperm = 0.0;
   }
  
   _relative_permeability[_qp] = relperm * _scaling;
   _drelative_permeability_ds[_qp] = drelperm * _dseff_ds * _scaling;
 }

◆ dRelativePermeability()

Real PorousFlowRelativePermeabilityVG::dRelativePermeability ( Real seff ) const

overrideprotectedvirtual

Derivative of relative permeability with respect to effective saturation.

Parameters

seff	effective saturation

Returns: derivative of relative permeability wrt effective saturation

Implements PorousFlowRelativePermeabilityBase.

Definition at line 83 of file PorousFlowRelativePermeabilityVG.C.

 {
   if (seff < _cut)
   {
     if (_wetting)
       return PorousFlowVanGenuchten::dRelativePermeability(seff, _m);
     else
       return PorousFlowVanGenuchten::dRelativePermeabilityNW(seff, _m);
   }
  
   return _cub1 + 2.0 * _cub2 * (seff - _cut) + 3.0 * _cub3 * Utility::pow<2>(seff - _cut);
 }

◆ effectiveSaturation()

Real PorousFlowRelativePermeabilityBase::effectiveSaturation ( Real saturation ) const

protectedvirtualinherited

Effective saturation of fluid phase.

Parameters

saturation true saturation

Returns: effective saturation

Definition at line 88 of file PorousFlowRelativePermeabilityBase.C.

 {
   return (saturation - _s_res) / (1.0 - _sum_s_res);
 }

Referenced by PorousFlowRelativePermeabilityBase::computeQpProperties().

◆ relativePermeability()

Real PorousFlowRelativePermeabilityVG::relativePermeability ( Real seff ) const

overrideprotectedvirtual

Relative permeability equation (must be overriden in derived class)

Parameters

seff	effective saturation

Returns: relative permeability

Implements PorousFlowRelativePermeabilityBase.

Definition at line 68 of file PorousFlowRelativePermeabilityVG.C.

 {
   if (seff < _cut)
   {
     if (_wetting)
       return PorousFlowVanGenuchten::relativePermeability(seff, _m);
     else
       return PorousFlowVanGenuchten::relativePermeabilityNW(seff, _m);
   }
  
   return _cub0 + _cub1 * (seff - _cut) + _cub2 * Utility::pow<2>(seff - _cut) +
          _cub3 * Utility::pow<3>(seff - _cut);
 }