ComputeEigenstrainBase Class Reference

ComputeEigenstrainBase is the base class for eigenstrain tensors. More...

#include <ComputeEigenstrainBase.h>

Inheritance diagram for ComputeEigenstrainBase:

Public Member Functions
	ComputeEigenstrainBase (const InputParameters &parameters)

Static Public Member Functions
static InputParameters	validParams ()

Protected Member Functions
virtual void	initQpStatefulProperties ()
virtual void	computeQpProperties ()
virtual void	computeQpEigenstrain ()=0
	Compute the eigenstrain and store in _eigenstrain. More...
Real	computeVolumetricStrainComponent (const Real volumetric_strain) const
	Helper function for models that compute the eigenstrain based on a volumetric strain. More...

Protected Attributes
const std::string	_base_name
	Base name prepended to material property name. More...
std::string	_eigenstrain_name
	Material property name for the eigenstrain tensor. More...
MaterialProperty< RankTwoTensor > &	_eigenstrain
	Stores the current total eigenstrain. More...
bool &	_step_zero
	Restartable data to check for the zeroth and first time steps for thermal calculations. More...

Detailed Description

ComputeEigenstrainBase is the base class for eigenstrain tensors.

Definition at line 26 of file ComputeEigenstrainBase.h.

Constructor & Destructor Documentation

ComputeEigenstrainBase()

ComputeEigenstrainBase::ComputeEigenstrainBase

(

const InputParameters &

parameters

)

Definition at line 31 of file ComputeEigenstrainBase.C.

  : Material(parameters),
    _base_name(isParamValid("base_name") ? getParam<std::string>("base_name") + "_" : ""),
    _eigenstrain_name(_base_name + getParam<std::string>("eigenstrain_name")),
    _eigenstrain(declareProperty<RankTwoTensor>(_eigenstrain_name)),
    _step_zero(declareRestartableData<bool>("step_zero", true))
{
}

Member Function Documentation

computeQpEigenstrain()

virtual void ComputeEigenstrainBase::computeQpEigenstrain ( )

protectedpure virtual

Compute the eigenstrain and store in _eigenstrain.

Implemented in ComputeEigenstrainFromInitialStress, ComputeReducedOrderEigenstrain, ComputeVariableBaseEigenStrain, and ComputeEigenstrain.

Referenced by computeQpProperties().

computeQpProperties()

void ComputeEigenstrainBase::computeQpProperties ( )

protectedvirtual

Definition at line 49 of file ComputeEigenstrainBase.C.

{
  if (_t_step >= 1)
    _step_zero = false;
 
  // Skip the eigenstrain calculation in step zero because no solution is computed during
  // the zeroth step, hence computing the eigenstrain in the zeroth step would result in
  // an incorrect calculation of mechanical_strain, which is stateful.
  if (!_step_zero)
    computeQpEigenstrain();
}

computeVolumetricStrainComponent()

Real ComputeEigenstrainBase::computeVolumetricStrainComponent ( const Real  volumetric_strain ) const

protected

Helper function for models that compute the eigenstrain based on a volumetric strain.

This function computes the diagonal components of the eigenstrain tensor as logarithmic strains.

Parameters

volumetric_strain

The current volumetric strain to be applied

Returns

Current strain in one direction due to volumetric strain, expressed as a logarithmic strain

Definition at line 62 of file ComputeEigenstrainBase.C.

{
  // The engineering strain in a given direction is:
  // epsilon_eng = cbrt(volumetric_strain + 1.0) - 1.0
  //
  // We need to provide this as a logarithmic strain to be consistent with the strain measure
  // used for finite strain:
  // epsilon_log = log(1.0 + epsilon_eng)
  //
  // This can be simplified down to a more direct form:
  // epsilon_log = log(cbrt(volumetric_strain + 1.0))
  // or:
  // epsilon_log = (1/3) log(volumetric_strain + 1.0)
 
  return std::log(volumetric_strain + 1.0) / 3.0;
}

initQpStatefulProperties()

void ComputeEigenstrainBase::initQpStatefulProperties ( )

protectedvirtual

Reimplemented in ComputeReducedOrderEigenstrain.

Definition at line 41 of file ComputeEigenstrainBase.C.

{
  // This property can be promoted to be stateful by other models that use it,
  // so it needs to be initalized.
  _eigenstrain[_qp].zero();
}

validParams()

InputParameters ComputeEigenstrainBase::validParams ( )

static

Definition at line 17 of file ComputeEigenstrainBase.C.

{
  InputParameters params = Material::validParams();
  params.addParam<std::string>("base_name",
                               "Optional parameter that allows the user to define "
                               "multiple mechanics material systems on the same "
                               "block, i.e. for multiple phases");
  params.addRequiredParam<std::string>("eigenstrain_name",
                                       "Material property name for the eigenstrain tensor computed "
                                       "by this model. IMPORTANT: The name of this property must "
                                       "also be provided to the strain calculator.");
  return params;
}

Referenced by ComputeEigenstrain::validParams(), ComputeEigenstrainFromInitialStress::validParams(), ComputeVolumetricEigenstrain::validParams(), ComputeVariableBaseEigenStrain::validParams(), ComputeReducedOrderEigenstrain::validParams(), and ComputeThermalExpansionEigenstrainBase::validParams().

Member Data Documentation

_base_name

const std::string ComputeEigenstrainBase::_base_name

protected

Base name prepended to material property name.

Definition at line 41 of file ComputeEigenstrainBase.h.

Referenced by ComputeReducedOrderEigenstrain::ComputeReducedOrderEigenstrain().

_eigenstrain

MaterialProperty<RankTwoTensor>& ComputeEigenstrainBase::_eigenstrain

protected

Stores the current total eigenstrain.

Definition at line 47 of file ComputeEigenstrainBase.h.

Referenced by ComputeEigenstrain::computeQpEigenstrain(), ComputeEigenstrainFromInitialStress::computeQpEigenstrain(), ComputeVariableBaseEigenStrain::computeQpEigenstrain(), ComputeReducedOrderEigenstrain::computeQpEigenstrain(), initQpStatefulProperties(), and ComputeReducedOrderEigenstrain::initQpStatefulProperties().

_eigenstrain_name

std::string ComputeEigenstrainBase::_eigenstrain_name

protected

Material property name for the eigenstrain tensor.

Definition at line 44 of file ComputeEigenstrainBase.h.

_step_zero

bool& ComputeEigenstrainBase::_step_zero

protected

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

Definition at line 60 of file ComputeEigenstrainBase.h.

Referenced by computeQpProperties().

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

• tensor_mechanics/include/materials/ComputeEigenstrainBase.h
• tensor_mechanics/src/materials/ComputeEigenstrainBase.C