Real
SlaveConstraint::computeQpResidual()
{
PenetrationInfo * pinfo = _point_to_info[_current_point];
const Node * node = pinfo->_node;
Real resid = pinfo->_contact_force(_component);
const Real area = nodalArea(*pinfo);
if (_formulation == CF_DEFAULT)
{
RealVectorValue distance_vec(_mesh.node(node->id()) - pinfo->_closest_point);
RealVectorValue pen_force(_penalty * distance_vec);
if (_normalize_penalty)
pen_force *= area;
if (_model == CM_FRICTIONLESS)
resid += pinfo->_normal(_component) * pinfo->_normal * pen_force;
else if (_model == CM_GLUED || _model == CM_COULOMB)
resid += pen_force(_component);
}
return _test[_i][_qp] * resid;
}
Real
MechanicalContactConstraint::computeQpResidual(Moose::ConstraintType type)
{
PenetrationInfo * pinfo = _penetration_locator._penetration_info[_current_node->id()];
computeContactForce(pinfo);
Real resid = pinfo->_contact_force(_component);
switch(type)
{
case Moose::Slave:
if (_formulation == CF_DEFAULT)
{
//Real distance = (*_current_node)(_component) - pinfo->_closest_point(_component);
//Real pen_force = _penalty * distance;
RealVectorValue distance_vec(*_current_node - pinfo->_closest_point);
RealVectorValue pen_force(_penalty * distance_vec);
if (_model == CM_FRICTIONLESS || _model == CM_EXPERIMENTAL)
resid += pinfo->_normal(_component) * pinfo->_normal * pen_force;
else if (_model == CM_GLUED || _model == CM_TIED || _model == CM_COULOMB)
resid += pen_force(_component);
}
return _test_slave[_i][_qp] * resid;
case Moose::Master:
return _test_master[_i][_qp] * -resid;
}
return 0;
}
void
ContactMaster::computeContactForce(PenetrationInfo * pinfo)
{
std::map<unsigned int, Real> & lagrange_multiplier = _penetration_locator._lagrange_multiplier;
const Node * node = pinfo->_node;
RealVectorValue res_vec;
// Build up residual vector
for (unsigned int i=0; i<_mesh_dimension; ++i)
{
long int dof_number = node->dof_number(0, _vars(i), 0);
res_vec(i) = _residual_copy(dof_number);
}
const Real area = nodalArea(*pinfo);
RealVectorValue distance_vec(_mesh.node(node->id()) - pinfo->_closest_point);
RealVectorValue pen_force(_penalty * distance_vec);
if (_normalize_penalty)
pen_force *= area;
RealVectorValue tan_residual(0,0,0);
if (_model == CM_FRICTIONLESS)
{
switch (_formulation)
{
case CF_DEFAULT:
pinfo->_contact_force = -pinfo->_normal * (pinfo->_normal * res_vec);
break;
case CF_PENALTY:
pinfo->_contact_force = pinfo->_normal * (pinfo->_normal * pen_force);
break;
case CF_AUGMENTED_LAGRANGE:
pinfo->_contact_force = (pinfo->_normal * (pinfo->_normal *
//( pen_force + (lagrange_multiplier[node->id()]/distance_vec.size())*distance_vec)));
( pen_force + lagrange_multiplier[node->id()] * pinfo->_normal)));
break;
default:
mooseError("Invalid contact formulation");
break;
}
pinfo->_mech_status=PenetrationInfo::MS_SLIPPING;
}
else if (_model == CM_COULOMB && _formulation == CF_PENALTY)
{
distance_vec = pinfo->_incremental_slip + (pinfo->_normal * (_mesh.node(node->id()) - pinfo->_closest_point)) * pinfo->_normal;
pen_force = _penalty * distance_vec;
if (_normalize_penalty)
pen_force *= area;
// Frictional capacity
// const Real capacity( _friction_coefficient * (pen_force * pinfo->_normal < 0 ? -pen_force * pinfo->_normal : 0) );
const Real capacity( _friction_coefficient * (res_vec * pinfo->_normal > 0 ? res_vec * pinfo->_normal : 0) );
// Elastic predictor
pinfo->_contact_force = pen_force + (pinfo->_contact_force_old - pinfo->_normal*(pinfo->_normal*pinfo->_contact_force_old));
RealVectorValue contact_force_normal( (pinfo->_contact_force*pinfo->_normal) * pinfo->_normal );
RealVectorValue contact_force_tangential( pinfo->_contact_force - contact_force_normal );
// Tangential magnitude of elastic predictor
const Real tan_mag( contact_force_tangential.size() );
if ( tan_mag > capacity )
{
pinfo->_contact_force = contact_force_normal + capacity * contact_force_tangential / tan_mag;
pinfo->_mech_status=PenetrationInfo::MS_SLIPPING;
}
else
{
pinfo->_mech_status=PenetrationInfo::MS_STICKING;
}
}
else if (_model == CM_GLUED ||
(_model == CM_COULOMB && _formulation == CF_DEFAULT))
{
switch (_formulation)
{
case CF_DEFAULT:
pinfo->_contact_force = -res_vec;
break;
case CF_PENALTY:
pinfo->_contact_force = pen_force;
break;
case CF_AUGMENTED_LAGRANGE:
pinfo->_contact_force = pen_force +
lagrange_multiplier[node->id()]*distance_vec/distance_vec.size();
break;
default:
mooseError("Invalid contact formulation");
break;
}
pinfo->_mech_status=PenetrationInfo::MS_STICKING;
}
else
{
mooseError("Invalid or unavailable contact model");
}
}
void
MechanicalContactConstraint::computeContactForce(PenetrationInfo * pinfo)
{
const Node * node = pinfo->_node;
RealVectorValue res_vec;
// Build up residual vector
for (unsigned int i=0; i<_mesh_dimension; ++i)
{
dof_id_type dof_number = node->dof_number(0, _vars(i), 0);
res_vec(i) = _residual_copy(dof_number);
}
RealVectorValue distance_vec(_mesh.node(node->id()) - pinfo->_closest_point);
const Real penalty = getPenalty(*pinfo);
RealVectorValue pen_force(penalty * distance_vec);
switch (_model)
{
case CM_FRICTIONLESS:
switch (_formulation)
{
case CF_KINEMATIC:
pinfo->_contact_force = -pinfo->_normal * (pinfo->_normal * res_vec);
break;
case CF_PENALTY:
pinfo->_contact_force = pinfo->_normal * (pinfo->_normal * pen_force);
break;
case CF_AUGMENTED_LAGRANGE:
pinfo->_contact_force = (pinfo->_normal * (pinfo->_normal *
( pen_force + pinfo->_lagrange_multiplier * pinfo->_normal)));
break;
default:
mooseError("Invalid contact formulation");
break;
}
pinfo->_mech_status=PenetrationInfo::MS_SLIPPING;
break;
case CM_COULOMB:
switch (_formulation)
{
case CF_KINEMATIC:
pinfo->_contact_force = -res_vec;
break;
case CF_PENALTY:
{
distance_vec = pinfo->_incremental_slip + (pinfo->_normal * (_mesh.node(node->id()) - pinfo->_closest_point)) * pinfo->_normal;
pen_force = penalty * distance_vec;
// Frictional capacity
// const Real capacity( _friction_coefficient * (pen_force * pinfo->_normal < 0 ? -pen_force * pinfo->_normal : 0) );
const Real capacity( _friction_coefficient * (res_vec * pinfo->_normal > 0 ? res_vec * pinfo->_normal : 0) );
// Elastic predictor
pinfo->_contact_force = pen_force + (pinfo->_contact_force_old - pinfo->_normal*(pinfo->_normal*pinfo->_contact_force_old));
RealVectorValue contact_force_normal( (pinfo->_contact_force*pinfo->_normal) * pinfo->_normal );
RealVectorValue contact_force_tangential( pinfo->_contact_force - contact_force_normal );
// Tangential magnitude of elastic predictor
const Real tan_mag( contact_force_tangential.size() );
if ( tan_mag > capacity )
{
pinfo->_contact_force = contact_force_normal + capacity * contact_force_tangential / tan_mag;
pinfo->_mech_status=PenetrationInfo::MS_SLIPPING;
}
else
pinfo->_mech_status=PenetrationInfo::MS_STICKING;
break;
}
case CF_AUGMENTED_LAGRANGE:
pinfo->_contact_force = pen_force +
pinfo->_lagrange_multiplier*distance_vec/distance_vec.size();
break;
default:
mooseError("Invalid contact formulation");
break;
}
break;
case CM_GLUED:
switch (_formulation)
{
case CF_KINEMATIC:
pinfo->_contact_force = -res_vec;
break;
case CF_PENALTY:
pinfo->_contact_force = pen_force;
break;
case CF_AUGMENTED_LAGRANGE:
pinfo->_contact_force = pen_force +
pinfo->_lagrange_multiplier*distance_vec/distance_vec.size();
break;
default:
mooseError("Invalid contact formulation");
break;
}
pinfo->_mech_status=PenetrationInfo::MS_STICKING;
break;
default:
mooseError("Invalid or unavailable contact model");
break;
}
}