ConstitutiveModel Class Reference

#include <ConstitutiveModel.h>

Inheritance diagram for ConstitutiveModel:

Public Member Functions
	ConstitutiveModel (const InputParameters &parameters)
virtual	~ConstitutiveModel ()
void	setQp (unsigned int qp)
	Sets the value of the variable _qp for inheriting classes. More...
virtual void	computeStress (const Elem &, const SymmElasticityTensor &elasticityTensor, const SymmTensor &stress_old, SymmTensor &strain_increment, SymmTensor &stress_new)
virtual bool	modifyStrainIncrement (const Elem &, SymmTensor &strain_increment, SymmTensor &d_strain_dT)
virtual bool	updateElasticityTensor (SymmElasticityTensor &)
virtual bool	applyThermalStrain (SymmTensor &strain_increment, SymmTensor &d_strain_dT)

Protected Attributes
const bool	_has_temp
const VariableValue &	_temperature
const VariableValue &	_temperature_old
const Real	_alpha
const Function *	_alpha_function
bool	_has_stress_free_temp
Real	_stress_free_temp
bool	_mean_alpha_function
Real	_ref_temp
bool &	_step_zero_cm
	Restartable data to check for the zeroth and first time steps. More...
bool &	_step_one_cm

Detailed Description

Definition at line 22 of file ConstitutiveModel.h.

Constructor & Destructor Documentation

ConstitutiveModel()

ConstitutiveModel::ConstitutiveModel

(

const InputParameters &

parameters

)

Definition at line 39 of file ConstitutiveModel.C.

  : Material(parameters),
    _has_temp(isCoupled("temp")),
    _temperature(_has_temp ? coupledValue("temp") : _zero),
    _temperature_old(_has_temp ? coupledValueOld("temp") : _zero),
    _alpha(parameters.isParamValid("thermal_expansion") ? getParam<Real>("thermal_expansion") : 0.),
    _alpha_function(parameters.isParamValid("thermal_expansion_function")
                        ? &getFunction("thermal_expansion_function")
                        : NULL),
    _has_stress_free_temp(isParamValid("stress_free_temperature")),
    _stress_free_temp(_has_stress_free_temp ? getParam<Real>("stress_free_temperature") : 0.0),
    _ref_temp(0.0),
    _step_zero_cm(declareRestartableData<bool>("step_zero_cm", true)),
    _step_one_cm(declareRestartableData<bool>("step_one_cm", true))
{
  if (parameters.isParamValid("thermal_expansion_function_type"))
  {
    if (!_alpha_function)
      mooseError("thermal_expansion_function_type can only be set when thermal_expansion_function "
                 "is used");
    MooseEnum tec = getParam<MooseEnum>("thermal_expansion_function_type");
    if (tec == "mean")
      _mean_alpha_function = true;
    else if (tec == "instantaneous")
      _mean_alpha_function = false;
    else
      mooseError("Invalid option for thermal_expansion_function_type");
  }
  else
    _mean_alpha_function = false;
 
  if (parameters.isParamValid("thermal_expansion_reference_temperature"))
  {
    if (!_alpha_function)
      mooseError("thermal_expansion_reference_temperature can only be set when "
                 "thermal_expansion_function is used");
    if (!_mean_alpha_function)
      mooseError("thermal_expansion_reference_temperature can only be set when "
                 "thermal_expansion_function_type = mean");
    _ref_temp = getParam<Real>("thermal_expansion_reference_temperature");
    if (!_has_temp)
      mooseError(
          "Cannot specify thermal_expansion_reference_temperature without coupling to temperature");
  }
  else if (_mean_alpha_function)
    mooseError("Must specify thermal_expansion_reference_temperature if "
               "thermal_expansion_function_type = mean");
}

~ConstitutiveModel()

virtual ConstitutiveModel::~ConstitutiveModel ( )

inlinevirtual

Definition at line 27 of file ConstitutiveModel.h.

{}

Member Function Documentation

applyThermalStrain()

bool ConstitutiveModel::applyThermalStrain ( SymmTensor &  strain_increment, SymmTensor &  d_strain_dT  )

virtual

Definition at line 106 of file ConstitutiveModel.C.

{
  if (_t_step >= 1)
    _step_zero_cm = false;
 
  if (_t_step >= 2)
    _step_one_cm = false;
 
  if (_has_temp && !_step_zero_cm)
  {
    Real inc_thermal_strain;
    Real d_thermal_strain_d_temp;
 
    Real old_temp;
    if (_step_one_cm && _has_stress_free_temp)
      old_temp = _stress_free_temp;
    else
      old_temp = _temperature_old[_qp];
 
    Real current_temp = _temperature[_qp];
 
    Real delta_t = current_temp - old_temp;
 
    Real alpha = _alpha;
 
    if (_alpha_function)
    {
      Point p;
      Real alpha_current_temp = _alpha_function->value(current_temp, p);
      Real alpha_old_temp = _alpha_function->value(old_temp, p);
      Real alpha_stress_free_temperature = _alpha_function->value(_stress_free_temp, p);
 
      if (_mean_alpha_function)
      {
        Real small(1e-6);
 
        Real numerator = alpha_current_temp * (current_temp - _ref_temp) -
                         alpha_old_temp * (old_temp - _ref_temp);
        Real denominator = 1.0 + alpha_stress_free_temperature * (_stress_free_temp - _ref_temp);
        if (denominator < small)
          mooseError("Denominator too small in thermal strain calculation");
        inc_thermal_strain = numerator / denominator;
        d_thermal_strain_d_temp = alpha_current_temp * (current_temp - _ref_temp);
      }
      else
      {
        inc_thermal_strain = delta_t * 0.5 * (alpha_current_temp + alpha_old_temp);
        d_thermal_strain_d_temp = alpha_current_temp;
      }
    }
    else
    {
      inc_thermal_strain = delta_t * alpha;
      d_thermal_strain_d_temp = alpha;
    }
 
    strain_increment.addDiag(-inc_thermal_strain);
    d_strain_dT.addDiag(-d_thermal_strain_d_temp);
  }
 
  bool modified = true;
  return modified;
}

Referenced by modifyStrainIncrement().

computeStress()

void ConstitutiveModel::computeStress ( const Elem &  , const SymmElasticityTensor &  elasticityTensor, const SymmTensor &  stress_old, SymmTensor &  strain_increment, SymmTensor &  stress_new  )

virtual

Reimplemented in ReturnMappingModel, CombinedCreepPlasticity, RateDepSmearCrackModel, and ElasticModel.

Definition at line 95 of file ConstitutiveModel.C.

{
  stress_new = elasticityTensor * strain_increment;
  stress_new += stress_old;
}

modifyStrainIncrement()

virtual bool ConstitutiveModel::modifyStrainIncrement ( const Elem &  , SymmTensor &  strain_increment, SymmTensor &  d_strain_dT  )

inlinevirtual

Reimplemented in CombinedCreepPlasticity.

Definition at line 38 of file ConstitutiveModel.h.

  {
    return applyThermalStrain(strain_increment, d_strain_dT);
  }

setQp()

void ConstitutiveModel::setQp

(

unsigned int

qp

)

Sets the value of the variable _qp for inheriting classes.

Definition at line 89 of file ConstitutiveModel.C.

{
  _qp = qp;
}

Referenced by CombinedCreepPlasticity::computeStress().

updateElasticityTensor()

virtual bool ConstitutiveModel::updateElasticityTensor ( SymmElasticityTensor &  )

inlinevirtual

Definition at line 44 of file ConstitutiveModel.h.

{ return false; }

Member Data Documentation

_alpha

const Real ConstitutiveModel::_alpha

protected

Definition at line 52 of file ConstitutiveModel.h.

Referenced by applyThermalStrain().

_alpha_function

const Function* ConstitutiveModel::_alpha_function

protected

Definition at line 53 of file ConstitutiveModel.h.

Referenced by applyThermalStrain(), and ConstitutiveModel().

_has_stress_free_temp

bool ConstitutiveModel::_has_stress_free_temp

protected

Definition at line 54 of file ConstitutiveModel.h.

Referenced by applyThermalStrain().

_has_temp

const bool ConstitutiveModel::_has_temp

protected

Definition at line 49 of file ConstitutiveModel.h.

Referenced by applyThermalStrain(), PowerLawCreepModel::computeStressInitialize(), and ConstitutiveModel().

_mean_alpha_function

bool ConstitutiveModel::_mean_alpha_function

protected

Definition at line 56 of file ConstitutiveModel.h.

Referenced by applyThermalStrain(), and ConstitutiveModel().

_ref_temp

Real ConstitutiveModel::_ref_temp

protected

Definition at line 57 of file ConstitutiveModel.h.

Referenced by applyThermalStrain(), and ConstitutiveModel().

_step_one_cm

bool& ConstitutiveModel::_step_one_cm

protected

Definition at line 61 of file ConstitutiveModel.h.

Referenced by applyThermalStrain().

_step_zero_cm

bool& ConstitutiveModel::_step_zero_cm

protected

Restartable data to check for the zeroth and first time steps.

Definition at line 60 of file ConstitutiveModel.h.

Referenced by applyThermalStrain().

_stress_free_temp

Real ConstitutiveModel::_stress_free_temp

protected

Definition at line 55 of file ConstitutiveModel.h.

Referenced by applyThermalStrain().

_temperature

const VariableValue& ConstitutiveModel::_temperature

protected

Definition at line 50 of file ConstitutiveModel.h.

Referenced by applyThermalStrain(), CombinedCreepPlasticity::computeStress(), PowerLawCreepModel::computeStressInitialize(), IsotropicTempDepHardening::computeYieldStress(), IsotropicPlasticity::computeYieldStress(), and IsotropicTempDepHardening::initializeHardeningFunctions().

_temperature_old

const VariableValue& ConstitutiveModel::_temperature_old

protected

Definition at line 51 of file ConstitutiveModel.h.

Referenced by applyThermalStrain().

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

• solid_mechanics/include/materials/ConstitutiveModel.h
• solid_mechanics/src/materials/ConstitutiveModel.C