Page MenuHomec4science

contact_mechanics_model.cc
No OneTemporary

File Metadata

Created
Sun, May 12, 11:09

contact_mechanics_model.cc

/**
* @file coontact_mechanics_model.cc
*
* @author Mohit Pundir <mohit.pundir@epfl.ch>
*
* @date creation: Tue May 08 2012
* @date last modification: Wed Feb 21 2018
*
* @brief Contact mechanics model
*
* @section LICENSE
*
* Copyright (©) 2010-2018 EPFL (Ecole Polytechnique Fédérale de Lausanne)
* Laboratory (LSMS - Laboratoire de Simulation en Mécanique des Solides)
*
* Akantu is free software: you can redistribute it and/or modify it under the
* terms of the GNU Lesser General Public License as published by the Free
* Software Foundation, either version 3 of the License, or (at your option) any
* later version.
*
* Akantu is distributed in the hope that it will be useful, but WITHOUT ANY
* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
* A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
* details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with Akantu. If not, see <http://www.gnu.org/licenses/>.
*
*/
/* -------------------------------------------------------------------------- */
#include "contact_mechanics_model.hh"
#include "boundary_condition_functor.hh"
#include "dumpable_inline_impl.hh"
#include "integrator_gauss.hh"
#include "shape_lagrange.hh"
#include "group_manager_inline_impl.hh"
#ifdef AKANTU_USE_IOHELPER
#include "dumper_iohelper_paraview.hh"
#endif
/* -------------------------------------------------------------------------- */
#include <algorithm>
/* -------------------------------------------------------------------------- */
namespace akantu {
/* -------------------------------------------------------------------------- */
ContactMechanicsModel::ContactMechanicsModel(
Mesh & mesh, UInt dim, const ID & id, const MemoryID & memory_id,
std::shared_ptr<DOFManager> dof_manager, const ModelType model_type)
: Model(mesh, model_type, dof_manager, dim, id, memory_id) {
AKANTU_DEBUG_IN();
this->registerFEEngineObject<MyFEEngineType>("ContactMechanicsModel", mesh,
Model::spatial_dimension);
#if defined(AKANTU_USE_IOHELPER)
this->mesh.registerDumper<DumperParaview>("contact_mechanics", id, true);
this->mesh.addDumpMeshToDumper("contact_mechanics", mesh,
Model::spatial_dimension, _not_ghost,
_ek_regular);
#endif
this->registerDataAccessor(*this);
this->detector =
std::make_unique<ContactDetector>(this->mesh, id + ":contact_detector");
registerFEEngineObject<MyFEEngineType>("ContactFacetsFEEngine", mesh,
Model::spatial_dimension - 1);
AKANTU_DEBUG_OUT();
}
/* -------------------------------------------------------------------------- */
ContactMechanicsModel::~ContactMechanicsModel() {
AKANTU_DEBUG_IN();
AKANTU_DEBUG_OUT();
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::initFullImpl(const ModelOptions & options) {
Model::initFullImpl(options);
// initalize the resolutions
if (this->parser.getLastParsedFile() != "") {
this->instantiateResolutions();
}
this->initResolutions();
this->initBC(*this, *displacement, *displacement_increment, *external_force);
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::instantiateResolutions() {
ParserSection model_section;
bool is_empty;
std::tie(model_section, is_empty) = this->getParserSection();
if (not is_empty) {
auto model_resolutions =
model_section.getSubSections(ParserType::_contact_resolution);
for (const auto & section : model_resolutions) {
this->registerNewResolution(section);
}
}
auto sub_sections =
this->parser.getSubSections(ParserType::_contact_resolution);
for (const auto & section : sub_sections) {
this->registerNewResolution(section);
}
if (resolutions.empty())
AKANTU_EXCEPTION("No contact resolutions where instantiated for the model"
<< getID());
are_resolutions_instantiated = true;
}
/* -------------------------------------------------------------------------- */
Resolution &
ContactMechanicsModel::registerNewResolution(const ParserSection & section) {
std::string res_name;
std::string res_type = section.getName();
std::string opt_param = section.getOption();
try {
std::string tmp = section.getParameter("name");
res_name = tmp; /** this can seem weird, but there is an ambiguous operator
* overload that i couldn't solve. @todo remove the
* weirdness of this code
*/
} catch (debug::Exception &) {
AKANTU_ERROR("A contact resolution of type \'"
<< res_type
<< "\' in the input file has been defined without a name!");
}
Resolution & res = this->registerNewResolution(res_name, res_type, opt_param);
res.parseSection(section);
return res;
}
/* -------------------------------------------------------------------------- */
Resolution & ContactMechanicsModel::registerNewResolution(
const ID & res_name, const ID & res_type, const ID & opt_param) {
AKANTU_DEBUG_ASSERT(resolutions_names_to_id.find(res_name) ==
resolutions_names_to_id.end(),
"A resolution with this name '"
<< res_name << "' has already been registered. "
<< "Please use unique names for resolutions");
UInt res_count = resolutions.size();
resolutions_names_to_id[res_name] = res_count;
std::stringstream sstr_res;
sstr_res << this->id << ":" << res_count << ":" << res_type;
ID res_id = sstr_res.str();
std::unique_ptr<Resolution> resolution =
ResolutionFactory::getInstance().allocate(res_type, spatial_dimension,
opt_param, *this, res_id);
resolutions.push_back(std::move(resolution));
return *(resolutions.back());
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::initResolutions() {
AKANTU_DEBUG_ASSERT(resolutions.size() != 0,
"No resolutions to initialize !");
if (!are_resolutions_instantiated)
instantiateResolutions();
// \TODO check if each resolution needs a initResolution() method
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::initModel() {
AKANTU_DEBUG_IN();
getFEEngine("ContactMechanicsModel").initShapeFunctions(_not_ghost);
getFEEngine("ContactMechanicsModel").initShapeFunctions(_ghost);
getFEEngine("ContactFacetsFEEngine").initShapeFunctions(_not_ghost);
getFEEngine("ContactFacetsFEEngine").initShapeFunctions(_ghost);
AKANTU_DEBUG_OUT();
}
/* -------------------------------------------------------------------------- */
FEEngine & ContactMechanicsModel::getFEEngineBoundary(const ID & name) {
return dynamic_cast<FEEngine &>(
getFEEngineClassBoundary<MyFEEngineType>(name));
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::initSolver(
TimeStepSolverType /*time_step_solver_type*/, NonLinearSolverType) {
// for alloc type of solvers
this->allocNodalField(this->displacement, spatial_dimension, "displacement");
this->allocNodalField(this->displacement_increment, spatial_dimension,
"displacement_increment");
this->allocNodalField(this->internal_force, spatial_dimension,
"internal_force");
this->allocNodalField(this->external_force, spatial_dimension,
"external_force");
this->allocNodalField(this->normal_force, spatial_dimension,
"normal_force");
this->allocNodalField(this->tangential_force, spatial_dimension,
"tangential_force");
this->allocNodalField(this->gaps, 1, "gaps");
this->allocNodalField(this->nodal_area, 1, "areas");
this->allocNodalField(this->blocked_dofs, 1, "blocked_dofs");
this->allocNodalField(this->contact_state, 1, "contact_state");
this->allocNodalField(this->previous_master_elements, 1, "previous_master_elements");
this->allocNodalField(this->normals, spatial_dimension, "normals");
auto surface_dimension = spatial_dimension - 1;
this->allocNodalField(this->tangents, surface_dimension*spatial_dimension,
"tangents");
this->allocNodalField(this->projections, surface_dimension,
"projections");
this->allocNodalField(this->previous_projections, surface_dimension,
"previous_projections");
this->allocNodalField(this->previous_tangents, surface_dimension*spatial_dimension,
"previous_tangents");
this->allocNodalField(this->tangential_tractions, surface_dimension,
"tangential_tractions");
this->allocNodalField(this->previous_tangential_tractions, surface_dimension,
"previous_tangential_tractions");
// todo register multipliers as dofs for lagrange multipliers
}
/* -------------------------------------------------------------------------- */
std::tuple<ID, TimeStepSolverType>
ContactMechanicsModel::getDefaultSolverID(const AnalysisMethod & method) {
switch (method) {
case _explicit_lumped_mass: {
return std::make_tuple("explicit_lumped",
TimeStepSolverType::_dynamic_lumped);
}
case _explicit_consistent_mass: {
return std::make_tuple("explicit", TimeStepSolverType::_dynamic);
}
case _static: {
return std::make_tuple("static", TimeStepSolverType::_static);
}
case _implicit_dynamic: {
return std::make_tuple("implicit", TimeStepSolverType::_dynamic);
}
default:
return std::make_tuple("unknown", TimeStepSolverType::_not_defined);
}
}
/* -------------------------------------------------------------------------- */
ModelSolverOptions ContactMechanicsModel::getDefaultSolverOptions(
const TimeStepSolverType & type) const {
ModelSolverOptions options;
switch (type) {
case TimeStepSolverType::_dynamic: {
options.non_linear_solver_type = NonLinearSolverType::_lumped;
options.integration_scheme_type["displacement"] =
IntegrationSchemeType::_central_difference;
options.solution_type["displacement"] = IntegrationScheme::_acceleration;
break;
}
case TimeStepSolverType::_dynamic_lumped: {
options.non_linear_solver_type = NonLinearSolverType::_lumped;
options.integration_scheme_type["displacement"] =
IntegrationSchemeType::_central_difference;
options.solution_type["displacement"] = IntegrationScheme::_acceleration;
break;
}
case TimeStepSolverType::_static: {
options.non_linear_solver_type =
NonLinearSolverType::_newton_raphson_contact;
options.integration_scheme_type["displacement"] =
IntegrationSchemeType::_pseudo_time;
options.solution_type["displacement"] = IntegrationScheme::_not_defined;
break;
}
default:
AKANTU_EXCEPTION(type << " is not a valid time step solver type");
break;
}
return options;
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::assembleResidual() {
AKANTU_DEBUG_IN();
/* ------------------------------------------------------------------------ */
// computes the internal forces
this->assembleInternalForces();
/* ------------------------------------------------------------------------ */
this->getDOFManager().assembleToResidual("displacement",
*this->internal_force, 1);
AKANTU_DEBUG_OUT();
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::assembleInternalForces() {
AKANTU_DEBUG_IN();
AKANTU_DEBUG_INFO("Assemble the contact forces");
UInt nb_nodes = mesh.getNbNodes();
this->internal_force->clear();
this->normal_force->clear();
this->tangential_force->clear();
internal_force->resize(nb_nodes, 0.);
normal_force->resize(nb_nodes, 0.);
tangential_force->resize(nb_nodes, 0.);
// assemble the forces due to contact
auto assemble = [&](auto && ghost_type) {
for (auto & resolution : resolutions) {
resolution->assembleInternalForces(ghost_type);
}
};
AKANTU_DEBUG_INFO("Assemble residual for local elements");
assemble(_not_ghost);
// assemble the stresses due to ghost elements
AKANTU_DEBUG_INFO("Assemble residual for ghost elements");
//assemble(_ghost);
// TODO : uncomment when developing code for parallelization,
// currently it addes the force twice for not ghost elements
// hence source of error
AKANTU_DEBUG_OUT();
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::search() {
// save the previous state
this->savePreviousState();
contact_elements.clear();
contact_elements.resize(0);
// this needs to be resized if cohesive elements are added
UInt nb_nodes = mesh.getNbNodes();
auto resize_arrays = [&](auto & internal_array) {
internal_array->clear();
internal_array->resize(nb_nodes, 0.);
};
resize_arrays(gaps);
resize_arrays(normals);
resize_arrays(tangents);
resize_arrays(projections);
resize_arrays(tangential_tractions);
resize_arrays(contact_state);
this->detector->search(contact_elements, *gaps,
*normals, *projections);
for (auto & gap : *gaps) {
if (gap < 0)
gap = std::abs(gap);
else
gap = -gap;
}
if (contact_elements.size() != 0) {
this->computeNodalAreas();
}
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::savePreviousState() {
AKANTU_DEBUG_IN();
// saving previous natural projections
previous_projections->clear();
previous_projections->resize(projections->size(), 0.);
(*previous_projections).copy(*projections);
// saving previous tangents
previous_tangents->clear();
previous_tangents->resize(tangents->size(), 0.);
(*previous_tangents).copy(*tangents);
// saving previous tangential traction
previous_tangential_tractions->clear();
previous_tangential_tractions->resize(tangential_tractions->size(), 0.);
(*previous_tangential_tractions).copy(*tangential_tractions);
previous_master_elements->clear();
previous_master_elements->resize(projections->size());
for (auto & element : contact_elements) {
(*previous_master_elements)[element.slave] = element.master;
}
AKANTU_DEBUG_OUT();
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::computeNodalAreas() {
UInt nb_nodes = mesh.getNbNodes();
nodal_area->clear();
external_force->clear();
nodal_area->resize(nb_nodes, 0.);
external_force->resize(nb_nodes, 0.);
auto & fem_boundary = this->getFEEngineBoundary("ContactMechanicsModel");
fem_boundary.computeNormalsOnIntegrationPoints(_not_ghost);
fem_boundary.computeNormalsOnIntegrationPoints(_ghost);
/*getFEEngine("ContactFacetsFEEngine").initShapeFunctions(getPositions(), _not_ghost);
getFEEngine("ContactFacetsFEEngine").initShapeFunctions(getPositions(), _ghost);
auto & fem_boundary = this->getFEEngineBoundary("ContactFacetsFEEngine");
fem_boundary.computeNormalsOnIntegrationPoints(_not_ghost);
fem_boundary.computeNormalsOnIntegrationPoints(_ghost);*/
switch (spatial_dimension) {
case 1: {
for (auto && area : *nodal_area) {
area = 1.;
}
break;
}
case 2:
case 3: {
this->applyBC(
BC::Neumann::FromHigherDim(Matrix<Real>::eye(spatial_dimension, 1)),
mesh.getElementGroup("contact_surface"));
for (auto && tuple :
zip(*nodal_area, make_view(*external_force, spatial_dimension))) {
auto & area = std::get<0>(tuple);
auto & force = std::get<1>(tuple);
for (auto & f : force)
area += pow(f, 2);
area = sqrt(area);
}
break;
}
default:
break;
}
this->external_force->clear();
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::printself(std::ostream & stream, int indent) const {
std::string space;
for (Int i = 0; i < indent; i++, space += AKANTU_INDENT)
;
stream << space << "Contact Mechanics Model [" << std::endl;
stream << space << " + id : " << id << std::endl;
stream << space << " + spatial dimension : " << Model::spatial_dimension
<< std::endl;
stream << space << " + fem [" << std::endl;
getFEEngine().printself(stream, indent + 2);
stream << space << AKANTU_INDENT << "]" << std::endl;
stream << space << " + resolutions [" << std::endl;
for (auto & resolution : resolutions) {
resolution->printself(stream, indent + 1);
}
stream << space << AKANTU_INDENT << "]" << std::endl;
stream << space << "]" << std::endl;
}
/* -------------------------------------------------------------------------- */
MatrixType ContactMechanicsModel::getMatrixType(const ID & matrix_id) {
if (matrix_id == "K")
return _symmetric;
return _mt_not_defined;
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::assembleMatrix(const ID & matrix_id) {
if (matrix_id == "K") {
this->assembleStiffnessMatrix();
}
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::assembleStiffnessMatrix() {
AKANTU_DEBUG_IN();
AKANTU_DEBUG_INFO("Assemble the new stiffness matrix");
if (!this->getDOFManager().hasMatrix("K")) {
this->getDOFManager().getNewMatrix("K", getMatrixType("K"));
}
for (auto & resolution : resolutions) {
resolution->assembleStiffnessMatrix(_not_ghost);
}
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::assembleLumpedMatrix(const ID & /*matrix_id*/) {
AKANTU_TO_IMPLEMENT();
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::beforeSolveStep() {
for (auto & resolution : resolutions)
resolution->beforeSolveStep();
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::afterSolveStep(bool converged) {
for (auto & resolution : resolutions)
resolution->afterSolveStep(converged);
}
/* -------------------------------------------------------------------------- */
#ifdef AKANTU_USE_IOHELPER
/* -------------------------------------------------------------------------- */
std::shared_ptr<dumpers::Field>
ContactMechanicsModel::createNodalFieldBool(const std::string &,
const std::string &, bool) {
return nullptr;
}
/* -------------------------------------------------------------------------- */
std::shared_ptr<dumpers::Field>
ContactMechanicsModel::createNodalFieldReal(const std::string & field_name,
const std::string & group_name,
bool padding_flag) {
std::map<std::string, Array<Real> *> real_nodal_fields;
real_nodal_fields["contact_force"] = this->internal_force;
real_nodal_fields["normal_force"] = this->normal_force;
real_nodal_fields["tangential_force"] = this->tangential_force;
real_nodal_fields["blocked_dofs"] = this->blocked_dofs;
real_nodal_fields["normals"] = this->normals;
real_nodal_fields["tangents"] = this->tangents;
real_nodal_fields["gaps"] = this->gaps;
real_nodal_fields["areas"] = this->nodal_area;
real_nodal_fields["contact_state"] = this->contact_state;
std::shared_ptr<dumpers::Field> field;
if (padding_flag)
field = this->mesh.createNodalField(real_nodal_fields[field_name],
group_name, 3);
else
field = this->mesh.createNodalField(real_nodal_fields[field_name],
group_name);
return field;
}
#else
/* -------------------------------------------------------------------------- */
std::shared_ptr<dumpers::Field>
ContactMechanicsModel::createNodalFieldBool(const std::string &,
const std::string &, bool) {
return nullptr;
}
/* -------------------------------------------------------------------------- */
std::shared_ptr<dumpers::Field>
ContactMechanicsModel::createNodalFieldReal(const std::string & ,
const std::string & , bool) {
return nullptr;
}
#endif
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::dump(const std::string & dumper_name) {
mesh.dump(dumper_name);
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::dump(const std::string & dumper_name, UInt step) {
mesh.dump(dumper_name, step);
}
/* ------------------------------------------------------------------------- */
void ContactMechanicsModel::dump(const std::string & dumper_name, Real time,
UInt step) {
mesh.dump(dumper_name, time, step);
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::dump() { mesh.dump(); }
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::dump(UInt step) { mesh.dump(step); }
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::dump(Real time, UInt step) {
mesh.dump(time, step);
}
/* -------------------------------------------------------------------------- */
UInt ContactMechanicsModel::getNbData(
const Array<Element> & elements, const SynchronizationTag & /*tag*/) const {
AKANTU_DEBUG_IN();
UInt size = 0;
UInt nb_nodes_per_element = 0;
for (const Element & el : elements) {
nb_nodes_per_element += Mesh::getNbNodesPerElement(el.type);
}
AKANTU_DEBUG_OUT();
return size;
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::packData(CommunicationBuffer & /*buffer*/,
const Array<Element> & /*elements*/,
const SynchronizationTag & /*tag*/) const {
AKANTU_DEBUG_IN();
AKANTU_DEBUG_OUT();
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::unpackData(CommunicationBuffer & /*buffer*/,
const Array<Element> & /*elements*/,
const SynchronizationTag & /*tag*/) {
AKANTU_DEBUG_IN();
AKANTU_DEBUG_OUT();
}
/* -------------------------------------------------------------------------- */
UInt ContactMechanicsModel::getNbData(
const Array<UInt> & dofs, const SynchronizationTag & /*tag*/) const {
AKANTU_DEBUG_IN();
UInt size = 0;
AKANTU_DEBUG_OUT();
return size * dofs.size();
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::packData(CommunicationBuffer & /*buffer*/,
const Array<UInt> & /*dofs*/,
const SynchronizationTag & /*tag*/) const {
AKANTU_DEBUG_IN();
AKANTU_DEBUG_OUT();
}
/* -------------------------------------------------------------------------- */
void ContactMechanicsModel::unpackData(CommunicationBuffer & /*buffer*/,
const Array<UInt> & /*dofs*/,
const SynchronizationTag & /*tag*/) {
AKANTU_DEBUG_IN();
AKANTU_DEBUG_OUT();
}
} // namespace akantu

Event Timeline