BidomainNeumannSurfaceTermAssembler.hpp

/*

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*/

#ifndef BIDOMAINNEUMANNSURFACETERMASSEMBLER_HPP_
#define BIDOMAINNEUMANNSURFACETERMASSEMBLER_HPP_

#include "AbstractFeSurfaceIntegralAssembler.hpp"

template<unsigned ELEMENT_DIM, unsigned SPACE_DIM>
class BidomainNeumannSurfaceTermAssembler : public AbstractFeSurfaceIntegralAssembler<ELEMENT_DIM,SPACE_DIM,2>
{
protected:
    virtual c_vector<double, 2*ELEMENT_DIM> ComputeVectorSurfaceTerm(
        const BoundaryElement<ELEMENT_DIM-1,SPACE_DIM>& rSurfaceElement,
        c_vector<double, ELEMENT_DIM>& rPhi,
        ChastePoint<SPACE_DIM>& rX);

public:
    BidomainNeumannSurfaceTermAssembler(AbstractTetrahedralMesh<ELEMENT_DIM,SPACE_DIM>* pMesh,
                                        BoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,2>* pBoundaryConditions)
        : AbstractFeSurfaceIntegralAssembler<ELEMENT_DIM,SPACE_DIM,2>(pMesh, pBoundaryConditions)
    {
    }
};

template <unsigned ELEMENT_DIM, unsigned SPACE_DIM>
c_vector<double, 2*ELEMENT_DIM> BidomainNeumannSurfaceTermAssembler<ELEMENT_DIM, SPACE_DIM>::ComputeVectorSurfaceTerm(
        const BoundaryElement<ELEMENT_DIM-1,SPACE_DIM>& rSurfaceElement,
        c_vector<double, ELEMENT_DIM>& rPhi,
        ChastePoint<SPACE_DIM>& rX)
{
    // D_times_gradu_dot_n = [D grad(u)].n, D=diffusion matrix
    double sigma_i_times_grad_phi_i_dot_n = this->mpBoundaryConditions->GetNeumannBCValue(&rSurfaceElement, rX, 0);
    double sigma_e_times_grad_phi_e_dot_n = this->mpBoundaryConditions->GetNeumannBCValue(&rSurfaceElement, rX, 1);

    c_vector<double, 2*ELEMENT_DIM> ret;
    for (unsigned i=0; i<ELEMENT_DIM; i++)
    {
        ret(2*i)   = rPhi(i)*sigma_i_times_grad_phi_i_dot_n;
        ret(2*i+1) = rPhi(i)*(sigma_i_times_grad_phi_i_dot_n + sigma_e_times_grad_phi_e_dot_n);
    }

    return ret;
}

#endif // BIDOMAINNEUMANNSURFACETERMASSEMBLER_HPP_