Line data    Source code

       1             : //* This file is part of the MOOSE framework
       2             : //* https://mooseframework.inl.gov
       3             : //*
       4             : //* All rights reserved, see COPYRIGHT for full restrictions
       5             : //* https://github.com/idaholab/moose/blob/master/COPYRIGHT
       6             : //*
       7             : //* Licensed under LGPL 2.1, please see LICENSE for details
       8             : //* https://www.gnu.org/licenses/lgpl-2.1.html
       9             : 
      10             : #include "KKSPhaseChemicalPotential.h"
      11             : #include "MathUtils.h"
      12             : 
      13             : using namespace MathUtils;
      14             : 
      15             : registerMooseObject("PhaseFieldApp", KKSPhaseChemicalPotential);
      16             : 
      17             : InputParameters
      18         211 : KKSPhaseChemicalPotential::validParams()
      19             : {
      20         211 :   InputParameters params = Kernel::validParams();
      21         211 :   params.addClassDescription("KKS model kernel to enforce the pointwise equality of phase chemical "
      22             :                              "potentials $dF_a/dc_a = dF_b/dc_b$. The non-linear variable of this "
      23             :                              "kernel is $c_a$.");
      24         422 :   params.addRequiredCoupledVar(
      25             :       "cb", "Phase b concentration"); // note that ca is u, the non-linear variable!
      26         422 :   params.addRequiredParam<MaterialPropertyName>("fa_name",
      27             :                                                 "Base name of the free energy function "
      28             :                                                 "Fa (f_name in the corresponding "
      29             :                                                 "derivative function material)");
      30         422 :   params.addRequiredParam<MaterialPropertyName>("fb_name",
      31             :                                                 "Base name of the free energy function "
      32             :                                                 "Fb (f_name in the corresponding "
      33             :                                                 "derivative function material)");
      34         422 :   params.addParam<Real>("ka",
      35         422 :                         1.0,
      36             :                         "Site fraction for the ca variable (specify this if ca is a sublattice "
      37             :                         "concentration, and make sure it is a true site fraction eg. 0.6666666) ");
      38         422 :   params.addParam<Real>("kb",
      39         422 :                         1.0,
      40             :                         "Site fraction for the cb variable (specify this if ca is a sublattice "
      41             :                         "concentration, and make sure it is a true site fraction eg. 0.6666666) ");
      42         422 :   params.addCoupledVar(
      43             :       "args_a",
      44             :       "Vector of further parameters to Fa (optional, to add in second cross derivatives of Fa)");
      45         422 :   params.addCoupledVar(
      46             :       "args_b",
      47             :       "Vector of further parameters to Fb (optional, to add in second cross derivatives of Fb)");
      48         211 :   return params;
      49           0 : }
      50             : 
      51         113 : KKSPhaseChemicalPotential::KKSPhaseChemicalPotential(const InputParameters & parameters)
      52             :   : DerivativeMaterialInterface<JvarMapKernelInterface<Kernel>>(parameters),
      53         113 :     _cb_var(coupled("cb")),
      54         113 :     _cb_name(coupledName("cb", 0)),
      55             :     // first derivatives
      56         113 :     _dfadca(getMaterialPropertyDerivative<Real>("fa_name", _var.name())),
      57         113 :     _dfbdcb(getMaterialPropertyDerivative<Real>("fb_name", _cb_name)),
      58             :     // second derivatives d2F/dx*dca for jacobian diagonal elements
      59         113 :     _d2fadca2(getMaterialPropertyDerivative<Real>("fa_name", _var.name(), _var.name())),
      60         113 :     _d2fbdcbca(getMaterialPropertyDerivative<Real>("fb_name", _cb_name, _var.name())),
      61         113 :     _d2fadcadarg(_n_args),
      62         113 :     _d2fbdcbdarg(_n_args),
      63             :     // site fractions
      64         226 :     _ka(getParam<Real>("ka")),
      65         339 :     _kb(getParam<Real>("kb"))
      66             : {
      67             : #ifdef DEBUG
      68             :   _console << "KKSPhaseChemicalPotential(" << name() << ") " << _var.name() << ' ' << _cb_name
      69             :            << '\n';
      70             : #endif
      71             : 
      72             :   // lookup table for the material properties representing the derivatives needed for the
      73             :   // off-diagonal jacobian
      74         284 :   for (std::size_t i = 0; i < _n_args; ++i)
      75             :   {
      76         171 :     _d2fadcadarg[i] = &getMaterialPropertyDerivative<Real>("fa_name", _var.name(), i);
      77         171 :     _d2fbdcbdarg[i] = &getMaterialPropertyDerivative<Real>("fb_name", _cb_name, i);
      78             :   }
      79         113 : }
      80             : 
      81             : void
      82          78 : KKSPhaseChemicalPotential::initialSetup()
      83             : {
      84         234 :   validateNonlinearCoupling<Real>("fa_name");
      85         156 :   validateNonlinearCoupling<Real>("fb_name");
      86          78 : }
      87             : 
      88             : Real
      89     7918000 : KKSPhaseChemicalPotential::computeQpResidual()
      90             : {
      91             :   // enforce _dfadca==_dfbdcb
      92     7918000 :   return _test[_i][_qp] * (_dfadca[_qp] / _ka - _dfbdcb[_qp] / _kb);
      93             : }
      94             : 
      95             : Real
      96     5301840 : KKSPhaseChemicalPotential::computeQpJacobian()
      97             : {
      98             :   // for on diagonal we return the d/dca derivative of the residual
      99     5301840 :   return _test[_i][_qp] * _phi[_j][_qp] * (_d2fadca2[_qp] / _ka - _d2fbdcbca[_qp] / _kb);
     100             : }
     101             : 
     102             : Real
     103     5534640 : KKSPhaseChemicalPotential::computeQpOffDiagJacobian(unsigned int jvar)
     104             : {
     105             :   // get the coupled variable jvar is referring to
     106             :   const unsigned int cvar = mapJvarToCvar(jvar);
     107             : 
     108     5534640 :   return _test[_i][_qp] * _phi[_j][_qp] *
     109     5534640 :          ((*_d2fadcadarg[cvar])[_qp] / _ka - (*_d2fbdcbdarg[cvar])[_qp] / _kb);
     110             : }