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/*=========================================================================
*
* Copyright NumFOCUS
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0.txt
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*=========================================================================*/
#ifndef itkFEMElement2DMembrane_hxx
#define itkFEMElement2DMembrane_hxx
namespace itk
{
namespace fem
{
template <typename TBaseClass>
Element2DMembrane<TBaseClass>::Element2DMembrane()
: Superclass()
{}
// ////////////////////////////////////////////////////////////////////////
/**
* Methods related to the physics of the problem.
*/
template <typename TBaseClass>
void
Element2DMembrane<TBaseClass>::GetStrainDisplacementMatrix(MatrixType & B, const MatrixType & shapeDgl) const
{
unsigned int p;
unsigned int Nn = this->GetNumberOfNodes();
B.set_size(4, 2 * Nn); // note minor difference from linear elasticity
// Copy the shape function derivatives to the B matrix.
for (unsigned int i = 0; i < Nn; ++i)
{
// Compute B index
p = i << 1;
// Compute B elements
B[0][p] = shapeDgl[0][i];
B[0][p + 1] = 0.0;
B[1][p] = 0.0;
B[1][p + 1] = shapeDgl[0][i];
B[2][p] = shapeDgl[1][i];
B[2][p + 1] = 0.0;
B[3][p] = 0.0;
B[3][p + 1] = shapeDgl[1][i];
}
}
template <typename TBaseClass>
void
Element2DMembrane<TBaseClass>::GetMassMatrix(MatrixType & Me) const
{
// Call the parent's get matrix function
Superclass::GetMassMatrix(Me);
// Since parent class doesn't have the material properties,
// we need to adjust Me matrix here for the density of the element.
Me = Me * m_mat->GetDensityHeatProduct();
}
template <typename TBaseClass>
void
Element2DMembrane<TBaseClass>::GetMaterialMatrix(MatrixType & D) const
{
unsigned int d = 4;
D.set_size(d, d);
D.fill(0.0);
// This is the main difference from the linear elasticity problem.
/* Material properties matrix. Simpler than linear elasticity. */
Float disot = m_mat->GetYoungsModulus();
for (unsigned int i = 0; i < d; ++i)
{
D[i][i] = disot;
}
}
template <typename TBaseClass>
void
Element2DMembrane<TBaseClass>::PrintSelf(std::ostream & os, Indent indent) const
{
Superclass::PrintSelf(os, indent);
os << indent << "Materials: " << this->m_mat << std::endl;
}
} // end namespace fem
} // end namespace itk
#endif
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