RichardsSeff1VGcut Class Reference

Effective saturation as a function of porepressure using the van Genuchten formula, but when p<p_cut use a linear instead, seff = a + b*p, which matches value and derivative at p=p_cut This is so seff=0 at a finite value of p rather than p=-infinity. More...

#include <RichardsSeff1VGcut.h>

Inheritance diagram for RichardsSeff1VGcut:

Public Member Functions
	RichardsSeff1VGcut (const InputParameters &parameters)
void	initialSetup ()
	just prints some (maybe) useful info to the console More...
Real	seff (std::vector< const VariableValue * > p, unsigned int qp) const
	effective saturation as a function of porepressure More...
void	dseff (std::vector< const VariableValue * > p, unsigned int qp, std::vector< Real > &result) const
	derivative of effective saturation as a function of porepressure More...
void	d2seff (std::vector< const VariableValue * > p, unsigned int qp, std::vector< std::vector< Real >> &result) const
	second derivative of effective saturation as a function of porepressure More...
void	initialize ()
void	execute ()
void	finalize ()

Protected Attributes
Real	_al
	van Genuchten alpha parameter More...
Real	_m
	van Genuchten m parameter More...
Real	_p_cut
	cutoff in pressure below which use a linear relationship instead of van-Genuchten expression. _p_cut < 0 More...
Real	_s_cut
	effective saturation at p=_p_cut More...
Real	_ds_cut
	derivative of effective saturation wrt p at p=_p_cut More...

Detailed Description

Effective saturation as a function of porepressure using the van Genuchten formula, but when p<p_cut use a linear instead, seff = a + b*p, which matches value and derivative at p=p_cut This is so seff=0 at a finite value of p rather than p=-infinity.

Note effective saturation is not a function of capillary pressure: i use porepressure instead, so seff = 1 for p >= 0.

Definition at line 31 of file RichardsSeff1VGcut.h.

Constructor & Destructor Documentation

RichardsSeff1VGcut()

RichardsSeff1VGcut::RichardsSeff1VGcut

(

const InputParameters &

parameters

)

Definition at line 34 of file RichardsSeff1VGcut.C.

  : RichardsSeff1VG(parameters),
    _al(getParam<Real>("al")),
    _m(getParam<Real>("m")),
    _p_cut(getParam<Real>("p_cut")),
    _s_cut(0),
    _ds_cut(0)
{
  _s_cut = RichardsSeffVG::seff(_p_cut, _al, _m);
  _ds_cut = RichardsSeffVG::dseff(_p_cut, _al, _m);
}

Member Function Documentation

d2seff()

void RichardsSeff1VGcut::d2seff ( std::vector< const VariableValue * >  p, unsigned int  qp, std::vector< std::vector< Real >> &  result  ) const

virtual

second derivative of effective saturation as a function of porepressure

Parameters

p	porepressure in the element. Note that (*p[0])[qp] is the porepressure at quadpoint qp
qp	the quad point to evaluate effective saturation at
result	the derivtives will be placed in this array

Reimplemented from RichardsSeff1VG.

Definition at line 81 of file RichardsSeff1VGcut.C.

{
  if ((*p[0])[qp] > _p_cut)
    return RichardsSeff1VG::d2seff(p, qp, result);
  else
    result[0][0] = 0;
}

dseff()

void RichardsSeff1VGcut::dseff ( std::vector< const VariableValue * >  p, unsigned int  qp, std::vector< Real > &  result  ) const

virtual

derivative of effective saturation as a function of porepressure

Parameters

p	porepressure in the element. Note that (*p[0])[qp] is the porepressure at quadpoint qp
qp	the quad point to evaluate effective saturation at
result	the derivtives will be placed in this array

Reimplemented from RichardsSeff1VG.

Definition at line 70 of file RichardsSeff1VGcut.C.

{
  if ((*p[0])[qp] > _p_cut)
    return RichardsSeff1VG::dseff(p, qp, result);
  else
    result[0] = _ds_cut;
}

execute()

void RichardsSeff::execute ( )

inherited

Definition at line 32 of file RichardsSeff.C.

{
}

finalize()

void RichardsSeff::finalize ( )

inherited

Definition at line 37 of file RichardsSeff.C.

{
}

initialize()

void RichardsSeff::initialize ( )

inherited

Definition at line 27 of file RichardsSeff.C.

{
}

initialSetup()

void RichardsSeff1VGcut::initialSetup

(

)

just prints some (maybe) useful info to the console

Definition at line 47 of file RichardsSeff1VGcut.C.

{
  _console << "cut VG Seff has p_cut=" << _p_cut << " so seff_cut=" << _s_cut
           << " and seff=0 at p=" << -_s_cut / _ds_cut + _p_cut << std::endl;
}

seff()

Real RichardsSeff1VGcut::seff ( std::vector< const VariableValue * >  p, unsigned int  qp  ) const

virtual

effective saturation as a function of porepressure

Parameters

p	porepressure in the element. Note that (*p[0])[qp] is the porepressure at quadpoint qp
qp	the quad point to evaluate effective saturation at

Reimplemented from RichardsSeff1VG.

Definition at line 54 of file RichardsSeff1VGcut.C.

{
  if ((*p[0])[qp] > _p_cut)
  {
    return RichardsSeff1VG::seff(p, qp);
  }
  else
  {
    Real seff_linear = _s_cut + _ds_cut * ((*p[0])[qp] - _p_cut);
    // return (seff_linear > 0 ? seff_linear : 0); // andy isn't sure of this - might be useful to
    // allow negative saturations
    return seff_linear;
  }
}

Member Data Documentation

_al

Real RichardsSeff1VGcut::_al

protected

van Genuchten alpha parameter

Definition at line 70 of file RichardsSeff1VGcut.h.

Referenced by RichardsSeff1VGcut().

_ds_cut

Real RichardsSeff1VGcut::_ds_cut

protected

derivative of effective saturation wrt p at p=_p_cut

Definition at line 82 of file RichardsSeff1VGcut.h.

Referenced by dseff(), initialSetup(), RichardsSeff1VGcut(), and seff().

_m

Real RichardsSeff1VGcut::_m

protected

van Genuchten m parameter

Definition at line 73 of file RichardsSeff1VGcut.h.

Referenced by RichardsSeff1VGcut().

_p_cut

Real RichardsSeff1VGcut::_p_cut

protected

cutoff in pressure below which use a linear relationship instead of van-Genuchten expression. _p_cut < 0

Definition at line 76 of file RichardsSeff1VGcut.h.

Referenced by d2seff(), dseff(), initialSetup(), RichardsSeff1VGcut(), and seff().

_s_cut

Real RichardsSeff1VGcut::_s_cut

protected

effective saturation at p=_p_cut

Definition at line 79 of file RichardsSeff1VGcut.h.

Referenced by initialSetup(), RichardsSeff1VGcut(), and seff().

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

• richards/include/userobjects/RichardsSeff1VGcut.h
• richards/src/userobjects/RichardsSeff1VGcut.C