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Oliver Sander authored[[Imported from SVN: r9654]]
Oliver Sander authored[[Imported from SVN: r9654]]
cosserat-continuum.cc 12.78 KiB
#include <config.h>
#include <fenv.h>
// Includes for the ADOL-C automatic differentiation library
// Need to come before (almost) all others.
#include <adolc/adouble.h>
#include <adolc/drivers/drivers.h> // use of "Easy to Use" drivers
#include <adolc/taping.h>
#undef overwrite // stupid: ADOL-C sets this to 1, so the name cannot be used
#include <dune/gfe/adolcnamespaceinjections.hh>
#include <dune/common/bitsetvector.hh>
#include <dune/common/parametertree.hh>
#include <dune/common/parametertreeparser.hh>
#include <dune/grid/uggrid.hh>
#include <dune/grid/onedgrid.hh>
#include <dune/grid/geometrygrid.hh>
#include <dune/grid/utility/structuredgridfactory.hh>
#include <dune/grid/io/file/gmshreader.hh>
#include <dune/fufem/boundarypatch.hh>
#include <dune/fufem/functionspacebases/p1nodalbasis.hh>
#include <dune/solvers/solvers/iterativesolver.hh>
#include <dune/solvers/norms/energynorm.hh>
#include <dune/gfe/rigidbodymotion.hh>
#include <dune/gfe/localgeodesicfeadolcstiffness.hh>
#include <dune/gfe/cosseratenergystiffness.hh>
#include <dune/gfe/cosseratvtkwriter.hh>
#include <dune/gfe/geodesicfeassembler.hh>
#include <dune/gfe/riemanniantrsolver.hh>
// grid dimension
const int dim = 2;
// Image space of the geodesic fe functions
typedef RigidBodyMotion<double,3> TargetSpace;
// Tangent vector of the image space
const int blocksize = TargetSpace::TangentVector::dimension;
using namespace Dune;
#if 1
// Dirichlet boundary data for the shear/wrinkling example
void dirichletValues(const FieldVector<double,dim>& in, FieldVector<double,3>& out,
double homotopy)
{
out = 0;
for (int i=0; i<dim; i++)
out[i] = in[i];
// if (out[1] > 1-1e-3)
if (out[1] > 0.18-1e-4)
out[0] += 0.003*homotopy;
}
#endif
#if 0
// Dirichlet boundary data for the 'twisted-strip' example
void dirichletValues(const FieldVector<double,dim>& in, FieldVector<double,3>& out,
double homotopy
)
{
if (not vIt->geometry().corner(0)[0] > upper[0]-1e-3)
return;
double angle = 8*M_PI;
angle *= homotopy;
// center of rotation
FieldVector<double,3> center(0);
center[1] = 0.5;
FieldMatrix<double,3,3> rotation(0);
rotation[0][0] = 1;
rotation[1][1] = std::cos(angle);
rotation[1][2] = -std::sin(angle);
rotation[2][1] = std::sin(angle);
rotation[2][2] = std::cos(angle);
FieldVector<double,3> inEmbedded(0);
for (int i=0; i<dim; i++)
inEmbedded[i] = in[i];
inEmbedded -= center;
rotation.mv(inEmbedded, out);
out += center;
}
#endif
/** \brief A constant vector-valued function, for simple Neumann boundary values */
struct NeumannFunction
: public Dune::VirtualFunction<FieldVector<double,dim>, FieldVector<double,3> >
{
NeumannFunction(const FieldVector<double,3> values,
double homotopyParameter)
: values_(values),
homotopyParameter_(homotopyParameter)
{}
void evaluate(const FieldVector<double, dim>& x, FieldVector<double,3>& out) const {
out = 0;
out.axpy(homotopyParameter_, values_);
}
FieldVector<double,3> values_;
double homotopyParameter_;
};
int main (int argc, char *argv[]) try
{
//feenableexcept(FE_INVALID);
typedef std::vector<TargetSpace> SolutionType;
// parse data file
ParameterTree parameterSet;
ParameterTreeParser::readINITree("cosserat-continuum.parset", parameterSet);
ParameterTreeParser::readOptions(argc, argv, parameterSet);
// read solver settings
const int numLevels = parameterSet.get<int>("numLevels");
int numHomotopySteps = parameterSet.get<int>("numHomotopySteps");
const double tolerance = parameterSet.get<double>("tolerance");
const int maxTrustRegionSteps = parameterSet.get<int>("maxTrustRegionSteps");
const double initialTrustRegionRadius = parameterSet.get<double>("initialTrustRegionRadius");
const int multigridIterations = parameterSet.get<int>("numIt");
const int nu1 = parameterSet.get<int>("nu1");
const int nu2 = parameterSet.get<int>("nu2");
const int mu = parameterSet.get<int>("mu");
const int baseIterations = parameterSet.get<int>("baseIt");
const double mgTolerance = parameterSet.get<double>("mgTolerance");
const double baseTolerance = parameterSet.get<double>("baseTolerance"); const bool instrumented = parameterSet.get<bool>("instrumented");
std::string resultPath = parameterSet.get("resultPath", "");
// ///////////////////////////////////////
// Create the grid
// ///////////////////////////////////////
typedef std::conditional<dim==1,OneDGrid,UGGrid<dim> >::type GridType;
shared_ptr<GridType> grid;
FieldVector<double,dim> lower = parameterSet.get<FieldVector<double,dim> >("lower");
FieldVector<double,dim> upper = parameterSet.get<FieldVector<double,dim> >("upper");
if (parameterSet.get<bool>("structuredGrid")) {
array<unsigned int,dim> elements = parameterSet.get<array<unsigned int,dim> >("elements");
grid = StructuredGridFactory<GridType>::createCubeGrid(lower, upper, elements);
} else {
std::string path = parameterSet.get<std::string>("path");
std::string gridFile = parameterSet.get<std::string>("gridFile");
grid = shared_ptr<GridType>(GmshReader<GridType>::read(path + "/" + gridFile));
}
grid->globalRefine(numLevels-1);
typedef GridType::LeafGridView GridView;
GridView gridView = grid->leafGridView();
typedef P1NodalBasis<GridView,double> FEBasis;
FEBasis feBasis(gridView);
SolutionType x(feBasis.size());
// /////////////////////////////////////////
// Read Dirichlet values
// /////////////////////////////////////////
BitSetVector<blocksize> dirichletNodes(feBasis.size(), false);
BitSetVector<1> neumannNodes(feBasis.size(), false);
GridType::Codim<dim>::LeafIterator vIt = gridView.begin<dim>();
GridType::Codim<dim>::LeafIterator vEndIt = gridView.end<dim>();
const GridView::IndexSet& indexSet = gridView.indexSet();
for (; vIt!=vEndIt; ++vIt) {
#if 0 // Boundary conditions for the cantilever example
if (vIt->geometry().corner(0)[0] < 1.0+1e-3 /* or vIt->geometry().corner(0)[0] > upper[0]-1e-3*/ ) {
// Only translation dofs are Dirichlet
for (int j=0; j<3; j++)
dirichletNodes[indexSet.index(*vIt)][j] = true;
}
if (vIt->geometry().corner(0)[0] > upper[0]-1e-3 )
neumannNodes[indexSet.index(*vIt)][0] = true;
#endif
#if 1 // Boundary conditions for the shearing/wrinkling example
if (vIt->geometry().corner(0)[1] < 1e-4 or vIt->geometry().corner(0)[1] > upper[1]-1e-4 ) {
// Only translation dofs are Dirichlet
for (int j=0; j<5; j++)
dirichletNodes[indexSet.index(*vIt)][j] = true;
}
#endif
#if 0 // Boundary conditions for the twisted-strip example
if (vIt->geometry().corner(0)[0] < lower[0]+1e-3 or vIt->geometry().corner(0)[0] > upper[0]-1e-3 ) {
// Only translation dofs are Dirichlet
for (int j=0; j<3; j++)
dirichletNodes[indexSet.index(*vIt)][j] = true;
}#endif
#if 0 // Boundary conditions for the L-shape example
if (vIt->geometry().corner(0)[0] < 1.0) {
// Only translation dofs are Dirichlet
for (int j=0; j<3; j++)
dirichletNodes[indexSet.index(*vIt)][j] = true;
}
if (vIt->geometry().corner(0)[1] < -239 )
neumannNodes[indexSet.index(*vIt)][0] = true;
#endif
}
//////////////////////////////////////////////////////////////////////////////
// Assemble Neumann term
//////////////////////////////////////////////////////////////////////////////
BoundaryPatch<GridView> neumannBoundary(gridView, neumannNodes);
std::cout << "Neumann boundary has " << neumannBoundary.numFaces() << " faces\n";
// //////////////////////////
// Initial solution
// //////////////////////////
vIt = gridView.begin<dim>();
for (; vIt!=vEndIt; ++vIt) {
int idx = indexSet.index(*vIt);
x[idx].r = 0;
for (int i=0; i<dim; i++)
x[idx].r[i] = vIt->geometry().corner(0)[i];
x[idx].r[2] = 0.002*std::cos(1e4*vIt->geometry().corner(0)[0]);
// x[idx].q is the identity, set by the default constructor
}
////////////////////////////////////////////////////////
// Main homotopy loop
////////////////////////////////////////////////////////
// Output initial iterate (of homotopy loop)
CosseratVTKWriter<GridType>::write(*grid,x, resultPath + "cosserat_homotopy_0");
for (int i=0; i<numHomotopySteps; i++) {
double homotopyParameter = (i+1)*(1.0/numHomotopySteps);
std::cout << "Homotopy step: " << i << ", parameter: " << homotopyParameter << std::endl;
// ////////////////////////////////////////////////////////////
// Create an assembler for the energy functional
// ////////////////////////////////////////////////////////////
const ParameterTree& materialParameters = parameterSet.sub("materialParameters");
shared_ptr<NeumannFunction> neumannFunction;
if (parameterSet.hasKey("neumannValues"))
neumannFunction = make_shared<NeumannFunction>(parameterSet.get<FieldVector<double,3> >("neumannValues"),
homotopyParameter);
std::cout << "Material parameters:" << std::endl;
materialParameters.report();
// Assembler using ADOL-C
CosseratEnergyLocalStiffness<GridView,
FEBasis::LocalFiniteElement,
3,adouble> cosseratEnergyADOLCLocalStiffness(materialParameters,
&neumannBoundary,
neumannFunction.get()); LocalGeodesicFEADOLCStiffness<GridView,
FEBasis::LocalFiniteElement,
TargetSpace> localGFEADOLCStiffness(&cosseratEnergyADOLCLocalStiffness);
GeodesicFEAssembler<FEBasis,TargetSpace> assembler(gridView, &localGFEADOLCStiffness);
// /////////////////////////////////////////////////
// Create a Riemannian trust-region solver
// /////////////////////////////////////////////////
RiemannianTrustRegionSolver<GridType,TargetSpace> solver;
solver.setup(*grid,
&assembler,
x,
dirichletNodes,
tolerance,
maxTrustRegionSteps,
initialTrustRegionRadius,
multigridIterations,
mgTolerance,
mu, nu1, nu2,
baseIterations,
baseTolerance,
instrumented);
////////////////////////////////////////////////////////
// Set Dirichlet values
////////////////////////////////////////////////////////
for (vIt=gridView.begin<dim>(); vIt!=vEndIt; ++vIt) {
int idx = indexSet.index(*vIt);
if (dirichletNodes[idx][0]) {
// Only the positions have Dirichlet values
dirichletValues(vIt->geometry().corner(0), x[idx].r,
homotopyParameter);
}
}
// /////////////////////////////////////////////////////
// Solve!
// /////////////////////////////////////////////////////
solver.setInitialIterate(x);
solver.solve();
x = solver.getSol();
// Output result of each homotopy step
std::stringstream iAsAscii;
iAsAscii << i+1;
CosseratVTKWriter<GridType>::write(*grid,x, resultPath + "cosserat_homotopy_" + iAsAscii.str());
}
// //////////////////////////////
// Output result
// //////////////////////////////
CosseratVTKWriter<GridType>::write(*grid,x, resultPath + "cosserat");
// finally: compute the average deformation of the Neumann boundary
// That is what we need for the locking tests
FieldVector<double,3> averageDef(0);
for (size_t i=0; i<x.size(); i++)
if (neumannNodes[i][0])
averageDef += x[i].r; averageDef /= neumannNodes.count();
std::cout << "mu_c = " << parameterSet.get<double>("materialParameters.mu_c") << " "
<< "kappa = " << parameterSet.get<double>("materialParameters.kappa") << " "
<< numLevels << " levels, average deflection: " << averageDef << std::endl;
// //////////////////////////////
} catch (Exception e) {
std::cout << e << std::endl;
}