This Kernel computes epsilon_ijk * stress_jk (sum over j and k) "i" is called _component in this class and epsilon is the permutation pseudo-tensor. More...

#include <MomentBalancing.h>

Inheritance diagram for MomentBalancing:

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Public Member Functions
	MomentBalancing (const InputParameters &parameters)

Static Public Member Functions
static InputParameters	validParams ()

Protected Member Functions
virtual Real	computeQpResidual ()

virtual Real	computeQpJacobian ()

virtual Real	computeQpOffDiagJacobian (unsigned int jvar)

Protected Attributes
const MaterialProperty< RankTwoTensor > &	_stress
	the stress tensor (not the moment stress) at the quad-point. More...

const MaterialProperty< RankFourTensor > &	_Jacobian_mult
	d(stress tensor)/(d strain tensor) Here strain_ij = grad_j disp_i + epsilon_ijk * wc_k More...

const unsigned int	_component
	The Kernel computes epsilon_{component j k}*stress_{j k}. More...

const unsigned int	_nrots

std::vector< unsigned int >	_wc_var
	the moose variable numbers for the Cosserat rotation degrees of freedom More...

const unsigned int	_ndisp

std::vector< unsigned int >	_disp_var
	the moose variable numbers for the displacements More...

Detailed Description

This Kernel computes epsilon_ijk * stress_jk (sum over j and k) "i" is called _component in this class and epsilon is the permutation pseudo-tensor.

This Kernel is added to CosseratStressDivergenceTensors to form the equilibrium equations for the Cosserat moment-stress.

Definition at line 35 of file MomentBalancing.h.

Constructor & Destructor Documentation

◆ MomentBalancing()

MomentBalancing::MomentBalancing ( const InputParameters & parameters )

Definition at line 42 of file MomentBalancing.C.

   : Kernel(parameters),
     _stress(getMaterialProperty<RankTwoTensor>("stress" +
                                                getParam<std::string>("appended_property_name"))),
     _Jacobian_mult(getMaterialProperty<RankFourTensor>(
         "Jacobian_mult" + getParam<std::string>("appended_property_name"))),
     _component(getParam<unsigned int>("component")),
     _nrots(coupledComponents("Cosserat_rotations")),
     _wc_var(_nrots),
     _ndisp(coupledComponents("displacements")),
     _disp_var(_ndisp)
 {
   if (_nrots != 3)
     mooseError("MomentBalancing: This Kernel is only defined for 3-dimensional simulations so 3 "
                "Cosserat rotation variables are needed");
   for (unsigned i = 0; i < _nrots; ++i)
     _wc_var[i] = coupled("Cosserat_rotations", i);
  
   if (_ndisp != 3)
     mooseError("MomentBalancing: This Kernel is only defined for 3-dimensional simulations so 3 "
                "displacement variables are needed");
   for (unsigned i = 0; i < _ndisp; ++i)
     _disp_var[i] = coupled("displacements", i);
  
   // Following check is necessary to ensure the correct Jacobian is calculated
   if (_wc_var[_component] != _var.number())
     mooseError("MomentBalancing: The variable for this Kernel must be equal to the Cosserat "
                "rotation variable defined by the \"component\" and the \"Cosserat_rotations\" "
                "parameters");
 }

Member Function Documentation

◆ computeQpJacobian()

Real MomentBalancing::computeQpJacobian ( )

protectedvirtual

Definition at line 84 of file MomentBalancing.C.

 {
   return ElasticityTensorTools::momentJacobianWC(
       _Jacobian_mult[_qp], _component, _component, _test[_i][_qp], _phi[_j][_qp]);
 }

◆ computeQpOffDiagJacobian()

Real MomentBalancing::computeQpOffDiagJacobian ( unsigned int jvar )

protectedvirtual

Definition at line 91 of file MomentBalancing.C.

 {
   // What does 2D look like here?
   for (unsigned v = 0; v < _ndisp; ++v)
     if (jvar == _disp_var[v])
       return ElasticityTensorTools::momentJacobian(
           _Jacobian_mult[_qp], _component, v, _test[_i][_qp], _grad_phi[_j][_qp]);
  
   // What does 2D look like here?
   for (unsigned v = 0; v < _nrots; ++v)
     if (jvar == _wc_var[v])
       return ElasticityTensorTools::momentJacobianWC(
           _Jacobian_mult[_qp], _component, v, _test[_i][_qp], _phi[_j][_qp]);
  
   return 0.0;
 }

◆ computeQpResidual()

Real MomentBalancing::computeQpResidual ( )

protectedvirtual

Definition at line 74 of file MomentBalancing.C.

 {
   Real the_sum = 0.0;
   for (unsigned int j = 0; j < LIBMESH_DIM; ++j)
     for (unsigned int k = 0; k < LIBMESH_DIM; ++k)
       the_sum += PermutationTensor::eps(_component, j, k) * _stress[_qp](j, k);
   return _test[_i][_qp] * the_sum;
 }

◆ validParams()

InputParameters MomentBalancing::validParams ( )

static

Definition at line 25 of file MomentBalancing.C.

 {
   InputParameters params = Kernel::validParams();
   params.addRequiredRangeCheckedParam<unsigned int>(
       "component",
       "component<3",
       "An integer corresponding to the direction the variable this "
       "kernel acts in. (0 for x, 1 for y, 2 for z)");
   params.addParam<std::string>(
       "appended_property_name", "", "Name appended to material properties to make them unique");
   params.addRequiredCoupledVar("Cosserat_rotations", "The 3 Cosserat rotation variables");
   params.addRequiredCoupledVar("displacements", "The 3 displacement variables");
   params.set<bool>("use_displaced_mesh") = false;
  
   return params;
 }

Member Data Documentation

◆ _component

const unsigned int MomentBalancing::_component

protected

The Kernel computes epsilon_{component j k}*stress_{j k}.

Definition at line 57 of file MomentBalancing.h.

Referenced by computeQpJacobian(), computeQpOffDiagJacobian(), computeQpResidual(), and MomentBalancing().

◆ _disp_var

std::vector<unsigned int> MomentBalancing::_disp_var

protected

the moose variable numbers for the displacements

Definition at line 69 of file MomentBalancing.h.

Referenced by computeQpOffDiagJacobian(), and MomentBalancing().

◆ _Jacobian_mult

const MaterialProperty<RankFourTensor>& MomentBalancing::_Jacobian_mult

protected

d(stress tensor)/(d strain tensor) Here strain_ij = grad_j disp_i + epsilon_ijk * wc_k

Definition at line 54 of file MomentBalancing.h.

Referenced by computeQpJacobian(), and computeQpOffDiagJacobian().

◆ _ndisp

const unsigned int MomentBalancing::_ndisp

protected

Definition at line 66 of file MomentBalancing.h.

Referenced by computeQpOffDiagJacobian(), and MomentBalancing().

◆ _nrots

const unsigned int MomentBalancing::_nrots

protected

Definition at line 60 of file MomentBalancing.h.

Referenced by computeQpOffDiagJacobian(), and MomentBalancing().

◆ _stress

const MaterialProperty<RankTwoTensor>& MomentBalancing::_stress

protected

the stress tensor (not the moment stress) at the quad-point.

Definition at line 48 of file MomentBalancing.h.

Referenced by computeQpResidual().

◆ _wc_var

std::vector<unsigned int> MomentBalancing::_wc_var

protected

the moose variable numbers for the Cosserat rotation degrees of freedom

Definition at line 63 of file MomentBalancing.h.

Referenced by computeQpOffDiagJacobian(), and MomentBalancing().

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

tensor_mechanics/include/kernels/MomentBalancing.h
tensor_mechanics/src/kernels/MomentBalancing.C

Public Member Functions

Static Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ MomentBalancing()

Member Function Documentation

◆ computeQpJacobian()

◆ computeQpOffDiagJacobian()

◆ computeQpResidual()

◆ validParams()

Member Data Documentation

◆ _component

◆ _disp_var

◆ _Jacobian_mult

◆ _ndisp

◆ _nrots

◆ _stress

◆ _wc_var