DiscreteNucleation Class Reference

Free energy penalty contribution to force the nucleation of subresolution particles. More...

#include <DiscreteNucleation.h>

Inheritance diagram for DiscreteNucleation:

Public Member Functions
	DiscreteNucleation (const InputParameters &params)
virtual void	computeProperties ()

Protected Attributes
unsigned int	_nvar
std::vector< unsigned int >	_op_index
	map op_names indices to _args indices More...
const std::vector< Real >	_op_values
	Target concentration values. More...
const Real	_penalty
	Nucleation free energy prefactor. More...
const unsigned int	_penalty_mode
	Match concentration exactly or use the target as a minumum or maximum value. More...
const DiscreteNucleationMap &	_map
	UserObject providing a map of currently active nuclei. More...

Detailed Description

Free energy penalty contribution to force the nucleation of subresolution particles.

Definition at line 24 of file DiscreteNucleation.h.

Constructor & Destructor Documentation

DiscreteNucleation()

DiscreteNucleation::DiscreteNucleation

(

const InputParameters &

params

)

Definition at line 36 of file DiscreteNucleation.C.

  : DerivativeFunctionMaterialBase(params),
    _nvar(coupledComponents("op_names")),
    _op_index(_nvar),
    _op_values(getParam<std::vector<Real>>("op_values")),
    _penalty(getParam<Real>("penalty")),
    _penalty_mode(getParam<MooseEnum>("penalty_mode")),
    _map(getUserObject<DiscreteNucleationMap>("map"))
{
  // check inputs
  if (_nvar != _op_values.size())
    mooseError("The op_names and op_values parameter vectors must have the same number of entries");
  if (_nvar != _args.size())
    mooseError("Internal error.");
 
  // get libMesh variable numbers
  for (unsigned int i = 0; i < _nvar; ++i)
    _op_index[i] = argIndex(coupled("op_names", i));
}

Member Function Documentation

computeProperties()

void DiscreteNucleation::computeProperties ( )

virtual

Definition at line 57 of file DiscreteNucleation.C.

{
  // check if a nucleation event list is available for the current element
  const std::vector<Real> & nucleus = _map.nuclei(_current_elem);
 
  // calculate penalty
  for (_qp = 0; _qp < _qrule->n_points(); ++_qp)
  {
    // clear penalty value
    if (_prop_F)
      (*_prop_F)[_qp] = 0.0;
 
    for (unsigned int i = 0; i < _nvar; ++i)
    {
      const unsigned ii = _op_index[i];
 
      // modify the penalty magnitude with the nucleus mask
      const Real penalty = _penalty * nucleus[_qp];
 
      // deviation from the target concentration
      Real dc = (*_args[ii])[_qp] - _op_values[i];
 
      // ignore above/below target values for min/max modes respectively
      if ((_penalty_mode == 1 && dc > 0.0) || (_penalty_mode == 2 && dc < 0.0))
        dc = 0.0;
 
      // build free energy correction
      if (_prop_F)
        (*_prop_F)[_qp] += dc * dc * penalty;
 
      // first derivative
      if (_prop_dF[ii])
        (*_prop_dF[ii])[_qp] = 2.0 * dc * penalty;
 
      // second derivatives
      for (unsigned int jj = ii; jj < _nvar; ++jj)
      {
        if (_prop_d2F[ii][jj])
          (*_prop_d2F[ii][jj])[_qp] = 2.0 * penalty;
 
        // third derivatives
        if (_third_derivatives)
          for (unsigned int kk = jj; kk < _nvar; ++kk)
            if (_prop_d3F[ii][jj][kk])
              (*_prop_d3F[ii][jj][kk])[_qp] = 0.0;
      }
    }
  }
}

Member Data Documentation

_map

const DiscreteNucleationMap& DiscreteNucleation::_map

protected

UserObject providing a map of currently active nuclei.

Definition at line 47 of file DiscreteNucleation.h.

Referenced by computeProperties().

_nvar

unsigned int DiscreteNucleation::_nvar

protected

Definition at line 32 of file DiscreteNucleation.h.

Referenced by computeProperties(), and DiscreteNucleation().

_op_index

std::vector<unsigned int> DiscreteNucleation::_op_index

protected

map op_names indices to _args indices

Definition at line 35 of file DiscreteNucleation.h.

Referenced by computeProperties(), and DiscreteNucleation().

_op_values

const std::vector<Real> DiscreteNucleation::_op_values

protected

Target concentration values.

Definition at line 38 of file DiscreteNucleation.h.

Referenced by computeProperties(), and DiscreteNucleation().

_penalty

const Real DiscreteNucleation::_penalty

protected

Nucleation free energy prefactor.

Definition at line 41 of file DiscreteNucleation.h.

Referenced by computeProperties().

_penalty_mode

const unsigned int DiscreteNucleation::_penalty_mode

protected

Match concentration exactly or use the target as a minumum or maximum value.

Definition at line 44 of file DiscreteNucleation.h.

Referenced by computeProperties().

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

• phase_field/include/materials/DiscreteNucleation.h
• phase_field/src/materials/DiscreteNucleation.C