Dear a users,
I tried to use the plate elements in getfem. I have simple code which
seems to work I can get the dof counts right, as a dynamics person, I
need the system matrices K and M, so can someone put some light on the
extraction of system matrices for the below code snippet. Maybe the code
could be buggy, but I should get the matrices from out of the model
bricks I guess. Any help is appreciated.
Best regards,
Umut
// standard headers
#include <iostream>
#include <vector>
#include <string>
#include <cstdlib>
#include <cassert>
#include <stdexcept>
// gmm++ headers, pay attention that this is a template
// library, so that no build is required.
#include <gmm/gmm.h>
#include <gmm/gmm_inoutput.h>
// getFem++ headers
#include <getfem/getfem_import.h>
#include <getfem/dal_bit_vector.h>
#include <getfem/getfem_mesh.h>
#include <getfem/getfem_mesh_fem.h>
#include <getfem/getfem_partial_mesh_fem.h>
#include <getfem/getfem_mesh_im.h>
#include <getfem/getfem_integration.h>
#include <getfem/getfem_assembling.h>
#include <getfem/getfem_modeling.h>
#include <getfem/getfem_regular_meshes.h>
#include <getfem/getfem_linearized_plates.h>
//
typedef getfem::modeling_standard_sparse_matrix sparse_matrix;
typedef getfem::modeling_standard_plain_vector plain_vector;
//using namespace getfem;
//using namespace gmm;
using namespace std;
using bgeot::scalar_type;
using bgeot::size_type; /* = unsigned long */
//
int main(int argc, char** argv) {
// try {
// if(argc!=3){
// throw std::runtime_error("Error in input parameters\nUsage: <binary>
<filename.msh> <gmshFormatSpecifier>");
// }
// mesh definition
getfem::mesh mesh;
// integration specifications
getfem::mesh_im mim(mesh), mim_subint(mesh);
// mesh fem definitions for the fields on the plate
// u3 out of plane definition
// ut in plane, membrane definitions
// theta rotation definitions
getfem::mesh_fem mf_u3(mesh);
getfem::mesh_fem mf_ut(mesh);
getfem::mesh_fem mf_theta(mesh);
// mesh fem for rhs and lame constants
getfem::mesh_fem mf_rhs(mesh);
getfem::mesh_fem mf_lame(mesh);
// plate thickness
scalar_type h=0.005;
scalar_type lambda = 70e9*.33/((1+0.33)*(1-2*0.33));
scalar_type mu = 70e9/(2*(1+0.33));
// mitc
bool mitc = true;
// eta for Kirchoff-Love '0' or Mindlin 'small'
scalar_type eta = 0;
//import_mesh(argv[1], argv[2], mshGmsh);
// there is one mesh definition and different mesh_fem definitions
// for different regions in definition
// getfem::import_mesh("gmshv2:./platecoarse.msh", mesh);
getfem::import_mesh("gmshv2:./shellMesh.msh", mesh);
if( mesh.has_region(1)){
std::cout << "Mesh has the specified region definitions" << std::endl;
}
// optional print out for the convexes(elements) of a specific
// region
cout << "Number of elements : " << mesh.nb_convex() << endl;
// assign fem definitions to the regions
mf_ut.set_qdim(2);
mf_theta.set_qdim(2);
// set the finite element method
getfem::pfem pf_ut = getfem::fem_descriptor("FEM_QK(2,1)");
getfem::pfem pf_u3 = getfem::fem_descriptor("FEM_QK(2,1)");
getfem::pfem pf_theta = getfem::fem_descriptor("FEM_QK(2,1)");
getfem::pintegration_method ppi =
getfem::int_method_descriptor("IM_GAUSS_PARALLELEPIPED(2, 10)");
getfem::pintegration_method ppi_ct =
getfem::int_method_descriptor("IM_GAUSS_PARALLELEPIPED(2, 1)");
mim.set_integration_method(mesh.convex_index(), ppi);
mim_subint.set_integration_method(mesh.convex_index(), ppi_ct);
mf_ut.set_finite_element(mesh.convex_index(), pf_ut);
mf_u3.set_finite_element(mesh.convex_index(), pf_u3);
mf_theta.set_finite_element(mesh.convex_index(), pf_theta);
//
mf_rhs.set_finite_element(mesh.convex_index(),pf_ut);
//for(getfem::mr_visitor i(mshGmsh.region(1)); !i.finished(); ++i){
// lameConsts.set_finite_element(i.cv(),
// getfem::fem_descriptor("FEM_QK(2, 0)"));
//}
size_type nb_dof_rhs = mf_rhs.nb_dof();
plain_vector F(nb_dof_rhs * 3);
plain_vector M(nb_dof_rhs * 2);
//
cout << "Number of dofs for ut: " << mf_ut.nb_dof() << endl;
cout << "Number of dofs for u3: " << mf_u3.nb_dof() << endl;
cout << "Number of dofs for theta: " << mf_theta.nb_dof() << endl;
// define a brick
getfem::mdbrick_abstract<> *ELAS, *SIMPLE(0);
// plate
getfem::mdbrick_isotropic_linearized_plate<>
ELAS1(mim, mim_subint, mf_ut, mf_u3, mf_theta, lambda, mu, h);
if(mitc) ELAS1.set_mitc();
ELAS = &ELAS1;
getfem::mdbrick_plate_source_term<>VOL_F(*ELAS,mf_rhs,F,M);
getfem::mdbrick_plate_clamped_support<> SIMPLE1
(VOL_F, 1, 0, getfem::AUGMENTED_CONSTRAINTS);
SIMPLE = &SIMPLE1;
getfem::mdbrick_plate_closing<> final_model(*SIMPLE, 0, 1);
cout << "Total number of variables : " << final_model.nb_dof() << endl;
return EXIT_SUCCESS;
}
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