#include <ComputeSurfaceTensionKKS.h>

Inheritance diagram for ComputeSurfaceTensionKKS:

Public Member Functions
	ComputeSurfaceTensionKKS (const InputParameters &parameters)

Static Public Member Functions
static InputParameters	validParams ()

Protected Member Functions
virtual void	computeQpProperties () override

Protected Attributes
const VariableValue &	_v
	Order parameter. More...

const VariableGradient &	_grad_v
	Gradient of order parameter. More...

const MaterialProperty< Real > &	_kappa
	Material property for gradient energy coefficient. More...

const MaterialProperty< Real > &	_g
	Material property for barrier function. More...

Real	_w
	double well height parameter More...

MaterialProperty< RankTwoTensor > &	_planar_stress

Detailed Description

Definition at line 22 of file ComputeSurfaceTensionKKS.h.

Constructor & Destructor Documentation

◆ ComputeSurfaceTensionKKS()

ComputeSurfaceTensionKKS::ComputeSurfaceTensionKKS ( const InputParameters & parameters )

Definition at line 34 of file ComputeSurfaceTensionKKS.C.

   : Material(parameters),
     _v(coupledValue("v")),
     _grad_v(coupledGradient("v")),
     _kappa(getMaterialProperty<Real>("kappa_name")),
     _g(getMaterialProperty<Real>("g")),
     _w(getParam<Real>("w")),
     _planar_stress(
         declareProperty<RankTwoTensor>(getParam<MaterialPropertyName>("planar_stress_name")))
 {
 }

Member Function Documentation

◆ computeQpProperties()

void ComputeSurfaceTensionKKS::computeQpProperties ( )

overrideprotectedvirtual

Definition at line 47 of file ComputeSurfaceTensionKKS.C.

 {
   auto & S = _planar_stress[_qp];
   S.zero();
  
   // compute norm square of the order parameter gradient
   const Real grad_norm_sq = _grad_v[_qp].norm_sq();
  
   const Real nx = _grad_v[_qp](0);
   const Real ny = _grad_v[_qp](1);
   const Real nz = _grad_v[_qp](2);
   Real fsum = _w * _g[_qp] + 0.5 * _kappa[_qp] * grad_norm_sq;
  
   S(0, 0) += fsum - _kappa[_qp] * nx * nx;
   S(0, 1) += -_kappa[_qp] * nx * ny;
   S(1, 1) += fsum - _kappa[_qp] * ny * ny;
   S(0, 2) += -_kappa[_qp] * nx * nz;
   S(1, 2) += -_kappa[_qp] * ny * nz;
   S(2, 2) += fsum - _kappa[_qp] * nz * nz;
  
   // fill in symmetrically
   S(1, 0) = S(0, 1);
   S(2, 0) = S(0, 2);
   S(2, 1) = S(1, 2);
 }

◆ validParams()

InputParameters ComputeSurfaceTensionKKS::validParams ( )

static

Definition at line 18 of file ComputeSurfaceTensionKKS.C.

 {
   InputParameters params = Material::validParams();
   params.addClassDescription(
       "Surface tension of an interface defined by the gradient of an order parameter");
   params.addCoupledVar("v",
                        "Order parameter that defines the interface, assumed to vary from 0 to 1.");
   params.addParam<MaterialPropertyName>("kappa_name", "kappa_op", "Gradient energy coefficient");
   params.addParam<MaterialPropertyName>("g", "g", "Barrier Function Material that provides g(eta)");
   params.addRequiredParam<Real>("w", "Double well height parameter");
   params.addParam<MaterialPropertyName>("planar_stress_name",
                                         "extra_stress",
                                         "Material property name for the interfacial planar stress");
   return params;
 }