Aux Kernel class to postprocess and output the strain and stress components and equivalents for peridynamic models excluding correspondence material models. More...

#include <NodalRankTwoPD.h>

Inheritance diagram for NodalRankTwoPD:

[legend]

Public Member Functions
	NodalRankTwoPD (const InputParameters &parameters)

Protected Member Functions
Real	computeValue () override

virtual RankTwoTensor	computeNodalTotalStrain ()
	Function to compute the total strain tensor at each discrete material point. More...

virtual RankTwoTensor	computeNodalMechanicalStrain ()
	Function to compute the elastic strain tensor at each discrete material point. More...

virtual RankTwoTensor	computeNodalStress ()
	Function to compute the stress tensor at each discrete materials point. More...

Protected Attributes
bool	_has_temp

MooseVariable *	_temp_var
	coupled temperature variable More...

MooseVariable *	_bond_status_var
	bond_status variable More...

const bool	_plane_stress
	plane stress problem or not More...

const Real	_temp_ref
	reference temperature More...

std::string	_rank_two_tensor
	name of rank two tensor to be processed: total_strain, mechanical_strain or stress More...

std::string	_output_type
	output type: component or scalar More...

MooseEnum	_scalar_type
	specific scalar type to be output More...

PeridynamicsMesh &	_pdmesh
	Reference to peridynamic mesh object. More...

const unsigned int	_dim
	Problem dimension. More...


bool	_scalar_out_of_plane_strain_coupled
	variable for generalized plane strain cases More...

const VariableValue &	_scalar_out_of_plane_strain


const Real	_youngs_modulus
	material constants More...

const Real	_poissons_ratio

const Real	_alpha


const unsigned int	_i
	component index More...

const unsigned int	_j


const Point	_point1
	Points for direction dependent scalar output. More...

const Point	_point2

std::vector< MooseVariable * >	_disp_var
	@ More...

RankFourTensor	_Cijkl
	elasticity tensor More...

Detailed Description

Aux Kernel class to postprocess and output the strain and stress components and equivalents for peridynamic models excluding correspondence material models.

Definition at line 26 of file NodalRankTwoPD.h.

Constructor & Destructor Documentation

◆ NodalRankTwoPD()

NodalRankTwoPD::NodalRankTwoPD ( const InputParameters & parameters )

Definition at line 58 of file NodalRankTwoPD.C.

   : AuxKernelBasePD(parameters),
     _has_temp(isCoupled("temperature")),
     _temp_var(_has_temp ? getVar("temperature", 0) : nullptr),
     _bond_status_var(&_subproblem.getStandardVariable(_tid, "bond_status")),
     _scalar_out_of_plane_strain_coupled(isCoupledScalar("scalar_out_of_plane_strain")),
     _scalar_out_of_plane_strain(_scalar_out_of_plane_strain_coupled
                                     ? coupledScalarValue("scalar_out_of_plane_strain")
                                     : _zero),
     _plane_stress(getParam<bool>("plane_stress")),
     _youngs_modulus(getParam<Real>("youngs_modulus")),
     _poissons_ratio(getParam<Real>("poissons_ratio")),
     _alpha(getParam<Real>("thermal_expansion_coeff")),
     _temp_ref(getParam<Real>("stress_free_temperature")),
     _rank_two_tensor(getParam<std::string>("rank_two_tensor")),
     _output_type(getParam<std::string>("output_type")),
     _scalar_type(getParam<MooseEnum>("scalar_type")),
     _i(getParam<unsigned int>("index_i")),
     _j(getParam<unsigned int>("index_j")),
     _point1(parameters.get<Point>("point1")),
     _point2(parameters.get<Point>("point2"))
 {
   if (!_var.isNodal())
     mooseError("NodalRankTwoPD operates on nodal variable!");
  
   if (coupledComponents("displacements") != _dim)
     mooseError("Number of displacements should be the same as problem dimension!");
   for (unsigned int i = 0; i < coupledComponents("displacements"); ++i)
     _disp_var.push_back(getVar("displacements", i));
  
   if (_rank_two_tensor == "stress" && !isParamValid("youngs_modulus") &&
       !isParamValid("poissons_ratio"))
     mooseError("Both Young's modulus and Poisson's ratio must be provided for stress calculation");
  
   std::vector<Real> iso_const(2);
   iso_const[0] =
       _youngs_modulus * _poissons_ratio / ((1.0 + _poissons_ratio) * (1.0 - 2.0 * _poissons_ratio));
   iso_const[1] = _youngs_modulus / (2.0 * (1.0 + _poissons_ratio));
  
   // fill elasticity tensor
   _Cijkl.fillFromInputVector(iso_const, RankFourTensor::symmetric_isotropic);
  
   if (_has_temp && !isParamValid("thermal_expansion_coeff"))
     mooseError("thermal_expansion_coeff is required when temperature is coupled");
  
   if (_output_type == "component" && !(isParamValid("index_i") || isParamValid("index_j")))
     mooseError("The output_type is 'component', but no 'index_i' and 'index_j' are provided!");
  
   if (_output_type == "scalar" && !isParamValid("scalar_type"))
     mooseError("The output_type is 'scalar', but no 'scalar_type' is provided!");
 }

Member Function Documentation

◆ computeNodalMechanicalStrain()

RankTwoTensor NodalRankTwoPD::computeNodalMechanicalStrain ( )

protectedvirtual

Function to compute the elastic strain tensor at each discrete material point.

Returns: The calculated elastic strain tensor

Definition at line 207 of file NodalRankTwoPD.C.

 {
   RankTwoTensor total_strain = computeNodalTotalStrain();
   RankTwoTensor delta(RankTwoTensor::initIdentity);
   RankTwoTensor thermal_strain;
  
   if (_has_temp)
     thermal_strain = _alpha * (_temp_var->getNodalValue(*_current_node) - _temp_ref) * delta;
  
   RankTwoTensor mechanical_strain = total_strain - thermal_strain;
  
   return mechanical_strain;
 }

Referenced by computeNodalStress(), and computeValue().

◆ computeNodalStress()

RankTwoTensor NodalRankTwoPD::computeNodalStress ( )

protectedvirtual

Function to compute the stress tensor at each discrete materials point.

Returns: The calculated stress tensor

Definition at line 222 of file NodalRankTwoPD.C.

 {
   return _Cijkl * computeNodalMechanicalStrain();
 }

Referenced by computeValue().

◆ computeNodalTotalStrain()

RankTwoTensor NodalRankTwoPD::computeNodalTotalStrain ( )

protectedvirtual

Function to compute the total strain tensor at each discrete material point.

Returns: The calculated total strain tensor

Definition at line 137 of file NodalRankTwoPD.C.

 {
   std::vector<dof_id_type> neighbors = _pdmesh.getNeighbors(_current_node->id());
   std::vector<dof_id_type> bonds = _pdmesh.getBonds(_current_node->id());
   Real horizon = _pdmesh.getHorizon(_current_node->id());
  
   // calculate the shape tensor and prepare the deformation gradient tensor
   RankTwoTensor shape, dgrad, delta(RankTwoTensor::initIdentity);
   shape.zero();
   dgrad.zero();
   if (_dim == 2)
     shape(2, 2) = dgrad(2, 2) = 1.0;
  
   RealGradient origin_vector(3), current_vector(3);
   origin_vector = 0.0;
   current_vector = 0.0;
  
   for (unsigned int j = 0; j < neighbors.size(); ++j)
   {
     Node * node_j = _pdmesh.nodePtr(neighbors[j]);
     Real vol_j = _pdmesh.getPDNodeVolume(neighbors[j]);
     for (unsigned int k = 0; k < _dim; ++k)
     {
       origin_vector(k) = (*node_j)(k) - (*_pdmesh.nodePtr(_current_node->id()))(k);
       current_vector(k) = origin_vector(k) + _disp_var[k]->getNodalValue(*node_j) -
                           _disp_var[k]->getNodalValue(*_current_node);
     }
     Real origin_length = origin_vector.norm();
     Real bond_status_ij = _bond_status_var->getElementalValue(_pdmesh.elemPtr(bonds[j]));
     for (unsigned int k = 0; k < _dim; ++k)
       for (unsigned int l = 0; l < _dim; ++l)
       {
         shape(k, l) +=
             vol_j * horizon / origin_length * origin_vector(k) * origin_vector(l) * bond_status_ij;
         dgrad(k, l) +=
             vol_j * horizon / origin_length * current_vector(k) * origin_vector(l) * bond_status_ij;
       }
   }
  
   // finalize the deformation gradient tensor
   dgrad *= shape.inverse();
  
   // the green-lagrange strain tensor
   RankTwoTensor total_strain = 0.5 * (dgrad.transpose() * dgrad - delta);
  
   if (_scalar_out_of_plane_strain_coupled)
     total_strain(2, 2) = _scalar_out_of_plane_strain[0];
   else if (_plane_stress)
   {
     if (_has_temp)
     {
       Real mstrain00 =
           (total_strain(0, 0) - _alpha * (_temp_var->getNodalValue(*_current_node) - _temp_ref));
       Real mstrain11 =
           (total_strain(1, 1) - _alpha * (_temp_var->getNodalValue(*_current_node) - _temp_ref));
       Real mstrain22 =
           -(_Cijkl(2, 2, 0, 0) * mstrain00 + _Cijkl(2, 2, 1, 1) * mstrain11) / _Cijkl(2, 2, 2, 2);
       total_strain(2, 2) =
           mstrain22 + _alpha * (_temp_var->getNodalValue(*_current_node) - _temp_ref);
     }
     else
       total_strain(2, 2) =
           -(_Cijkl(2, 2, 0, 0) * total_strain(0, 0) + _Cijkl(2, 2, 1, 1) * total_strain(1, 1)) /
           _Cijkl(2, 2, 2, 2);
   }
  
   return total_strain;
 }

Referenced by computeNodalMechanicalStrain(), and computeValue().

◆ computeValue()

Real NodalRankTwoPD::computeValue ( )

overrideprotected

Definition at line 111 of file NodalRankTwoPD.C.

 {
   Real val = 0.0;
   RankTwoTensor tensor;
   Point p = Point(0, 0, 0);
   if (_rank_two_tensor == "total_strain")
     tensor = computeNodalTotalStrain();
   else if (_rank_two_tensor == "mechanical_strain")
     tensor = computeNodalMechanicalStrain();
   else if (_rank_two_tensor == "stress")
     tensor = computeNodalStress();
   else
     mooseError("NodalRankTwoPD Error: Pass valid rank two tensor: total_strain, "
                "mechanical_strain or stress");
  
   if (_output_type == "component")
     val = RankTwoScalarTools::component(tensor, _i, _j);
   else if (_output_type == "scalar")
     val = RankTwoScalarTools::getQuantity(tensor, _scalar_type, _point1, _point2, _q_point[_qp], p);
   else
     mooseError("NodalRankTwoPD Error: Pass valid output type - component or scalar");
  
   return val;
 }

Member Data Documentation

◆ _alpha

const Real NodalRankTwoPD::_alpha

protected

Definition at line 71 of file NodalRankTwoPD.h.

Referenced by computeNodalMechanicalStrain(), and computeNodalTotalStrain().

◆ _bond_status_var

MooseVariable* NodalRankTwoPD::_bond_status_var

protected

bond_status variable

Definition at line 58 of file NodalRankTwoPD.h.

Referenced by computeNodalTotalStrain().

◆ _Cijkl

RankFourTensor NodalRankTwoPD::_Cijkl

protected

elasticity tensor

Definition at line 100 of file NodalRankTwoPD.h.

Referenced by computeNodalStress(), computeNodalTotalStrain(), and NodalRankTwoPD().

◆ _dim

const unsigned int AuxKernelBasePD::_dim

protectedinherited

Problem dimension.

Definition at line 33 of file AuxKernelBasePD.h.

Referenced by computeNodalTotalStrain(), and NodalRankTwoPD().

◆ _disp_var

std::vector<MooseVariable *> NodalRankTwoPD::_disp_var

protected

@

displacement variables

Definition at line 97 of file NodalRankTwoPD.h.

Referenced by computeNodalTotalStrain(), and NodalRankTwoPD().

◆ _has_temp

bool NodalRankTwoPD::_has_temp

protected

Definition at line 52 of file NodalRankTwoPD.h.

Referenced by computeNodalMechanicalStrain(), computeNodalTotalStrain(), and NodalRankTwoPD().

◆ _i

const unsigned int NodalRankTwoPD::_i

protected

component index

Definition at line 87 of file NodalRankTwoPD.h.

Referenced by computeValue().

◆ _j

const unsigned int NodalRankTwoPD::_j

protected

Definition at line 88 of file NodalRankTwoPD.h.

Referenced by computeValue().

◆ _output_type

std::string NodalRankTwoPD::_output_type

protected

output type: component or scalar

Definition at line 81 of file NodalRankTwoPD.h.

Referenced by computeValue(), and NodalRankTwoPD().

◆ _pdmesh

PeridynamicsMesh& AuxKernelBasePD::_pdmesh

protectedinherited

Reference to peridynamic mesh object.

Definition at line 30 of file AuxKernelBasePD.h.

Referenced by computeNodalTotalStrain(), BoundaryOffsetPD::computeValue(), and NodalVolumePD::computeValue().

◆ _plane_stress

const bool NodalRankTwoPD::_plane_stress

protected

plane stress problem or not

Definition at line 66 of file NodalRankTwoPD.h.

Referenced by computeNodalTotalStrain().

◆ _point1

const Point NodalRankTwoPD::_point1

protected

Points for direction dependent scalar output.

Definition at line 92 of file NodalRankTwoPD.h.

Referenced by computeValue().

◆ _point2

const Point NodalRankTwoPD::_point2

protected

Definition at line 93 of file NodalRankTwoPD.h.

Referenced by computeValue().

◆ _poissons_ratio

const Real NodalRankTwoPD::_poissons_ratio

protected

Definition at line 70 of file NodalRankTwoPD.h.

Referenced by NodalRankTwoPD().

◆ _rank_two_tensor

std::string NodalRankTwoPD::_rank_two_tensor

protected

name of rank two tensor to be processed: total_strain, mechanical_strain or stress

Definition at line 78 of file NodalRankTwoPD.h.

Referenced by computeValue(), and NodalRankTwoPD().

◆ _scalar_out_of_plane_strain

const VariableValue& NodalRankTwoPD::_scalar_out_of_plane_strain

protected

Definition at line 62 of file NodalRankTwoPD.h.

Referenced by computeNodalTotalStrain().

◆ _scalar_out_of_plane_strain_coupled

bool NodalRankTwoPD::_scalar_out_of_plane_strain_coupled

protected

variable for generalized plane strain cases

Definition at line 61 of file NodalRankTwoPD.h.

Referenced by computeNodalTotalStrain().

◆ _scalar_type

MooseEnum NodalRankTwoPD::_scalar_type

protected

specific scalar type to be output

Definition at line 84 of file NodalRankTwoPD.h.

Referenced by computeValue().

◆ _temp_ref

const Real NodalRankTwoPD::_temp_ref

protected

reference temperature

Definition at line 75 of file NodalRankTwoPD.h.

Referenced by computeNodalMechanicalStrain(), and computeNodalTotalStrain().

◆ _temp_var

MooseVariable* NodalRankTwoPD::_temp_var

protected

coupled temperature variable

Definition at line 55 of file NodalRankTwoPD.h.

Referenced by computeNodalMechanicalStrain(), and computeNodalTotalStrain().

◆ _youngs_modulus

const Real NodalRankTwoPD::_youngs_modulus

protected

material constants

Definition at line 69 of file NodalRankTwoPD.h.

Referenced by NodalRankTwoPD().

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

peridynamics/include/auxkernels/NodalRankTwoPD.h
peridynamics/src/auxkernels/NodalRankTwoPD.C

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ NodalRankTwoPD()

Member Function Documentation

◆ computeNodalMechanicalStrain()

◆ computeNodalStress()

◆ computeNodalTotalStrain()

◆ computeValue()

Member Data Documentation

◆ _alpha

◆ _bond_status_var

◆ _Cijkl

◆ _dim

◆ _disp_var

◆ _has_temp

◆ _i

◆ _j

◆ _output_type

◆ _pdmesh

◆ _plane_stress

◆ _point1

◆ _point2

◆ _poissons_ratio

◆ _rank_two_tensor

◆ _scalar_out_of_plane_strain

◆ _scalar_out_of_plane_strain_coupled

◆ _scalar_type

◆ _temp_ref

◆ _temp_var

◆ _youngs_modulus