Op_Grad_DG.cpp

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#include <Op_Grad_DG.h>
#include <Check_espace_virtuel.h>
#include <Domaine_Cl_DG.h>
#include <Navier_Stokes_std.h>
#include <Schema_Temps_base.h>
#include <Probleme_base.h>
#include <EcrFicPartage.h>
#include <Matrice_Morse.h>
#include <Matrix_tools.h>
#include <Array_tools.h>
#include <SFichier.h>
#include <Debog.h>
#include <BasisFunction.h>
 
Implemente_instanciable(Op_Grad_DG, "Op_Grad_DG", Operateur_Grad_base);
 
Sortie& Op_Grad_DG::printOn(Sortie& s) const { return s << que_suis_je(); }
 
Entree& Op_Grad_DG::readOn(Entree& s) { return s; }
 
/**
 * @brief Associates the operator with a DG domain and its boundary conditions.
 * @param domaine_dis    The discretized domain, expected to be a Domaine_DG.
 * @param domaine_Cl_dis The boundary condition container, expected to be a Domaine_Cl_DG.
 */
void Op_Grad_DG::associer(const Domaine_dis_base& domaine_dis, const Domaine_Cl_dis_base& domaine_Cl_dis, const Champ_Inc_base&)
{
  le_dom_DG = ref_cast(Domaine_DG, domaine_dis);
  le_dcl_DG = ref_cast(Domaine_Cl_DG, domaine_Cl_dis);
}
 
/**
 * @brief Sizes the velocity-pressure matrix block for the gradient operator.
 *
 * @details Builds the sparsity pattern of the rectangular matrix mapping pressure DOFs
 * to velocity DOFs. Each velocity DOF of element T is coupled to all pressure DOFs of
 * T and its face-neighbours, as given by the pre-computed stencil. The resulting matrix
 * has size_v rows (velocity global DOFs) and size_p columns (pressure global DOFs).
 *
 * Returns immediately if "pression" is absent from matrices or is treated semi-implicitly.
 *
 * @param matrices  Map of matrix name → Matrice_Morse pointer to be sized.
 * @param semi_impl Map of semi-implicit field names; if "pression" is present, returns immediately.
 */
void Op_Grad_DG::dimensionner_blocs(matrices_t matrices, const tabs_t& semi_impl) const
{
  if (!matrices.count("pression")) return; //rien a faire
  if (semi_impl.count("pression"))
    return; // semi-implicite -> rien a dimensionner
 
  Matrice_Morse *mat = matrices["pression"], mat2;
 
  const Domaine_DG& domaine = le_dom_DG.valeur();
 
  int order_v = Option_DG::Get_order_for("vitesse");
  int order_p = Option_DG::Get_order_for("pression");
 
  const BasisFunction& bfunc_v = domaine.get_basisFunction(order_v);
  const int nb_bfunc_v = bfunc_v.nb_bfunc();
 
  const BasisFunction& bfunc_p = domaine.get_basisFunction(order_p);
  const int nb_bfunc_p = bfunc_p.nb_bfunc();
 
  int dim = Objet_U::dimension;
  const IntTab& indices_glob_elem_v = bfunc_v.indices_glob_elem(dim);
  const IntTab& indices_glob_elem_p = bfunc_p.indices_glob_elem();
 
  int nb_elem_tot = domaine.nb_elem_tot();
 
  int size_row = indices_glob_elem_v(nb_elem_tot);
  int size_col = indices_glob_elem_p(nb_elem_tot);
 
  mat2.dimensionner(size_row, size_col, 0);
 
  auto& tab1 = mat2.get_set_tab1();
  auto& tab2 = mat2.get_set_tab2();
  auto& coeff = mat2.get_set_coeff();
  coeff = 0;
 
  const Stencil& stencil_sorted = domaine.get_stencil_sorted();
  const int nb_stencil_max = stencil_sorted.dimension(1);
 
  int nb_indices_line;
  int row, col, indice;
 
  tab1(0) = 1;
  for (int nelem = 0; nelem < nb_elem_tot; nelem++)
    {
      nb_indices_line = 0;
      for (int k = 0; k < nb_stencil_max; k++)
        {
          if (stencil_sorted(nelem, k) < 0)
            break;
          nb_indices_line += nb_bfunc_p;
        }
      for (int k = 0; k < nb_bfunc_v * dim; k++)
        tab1(indices_glob_elem_v(nelem) + k + 1) = nb_indices_line + tab1(indices_glob_elem_v(nelem) + k);
    }
 
  mat2.dimensionner(size_row, size_col, tab1(size_row) - 1);
 
  for (int nelem = 0; nelem < nb_elem_tot; nelem++)
    {
      row = tab1[indices_glob_elem_v(nelem)] - 1;
      nb_indices_line = tab1[indices_glob_elem_v(nelem) + 1] - tab1[indices_glob_elem_v(nelem)];
      indice = 0;
 
      for (int i = 0; i < nb_bfunc_v*dim; i++)
        {
          for (int k = 0; k < nb_stencil_max; k++)
            {
              if (stencil_sorted(nelem, k) < 0)
                break;
              col = indices_glob_elem_p(stencil_sorted(nelem, k)) + 1;
              for (int j = 0 ;  j < nb_bfunc_p; j++)
                tab2[row + indice + j + k*nb_bfunc_p] = col + j;
            }
          indice += nb_indices_line;
        }
    }
  mat2.is_sorted_stencil();
  assert(mat2.is_sorted_stencil());
  mat->nb_colonnes() ? *mat += mat2 : *mat = mat2;
}
 
/**
 * @brief Assembles the DG gradient operator into the matrix and right-hand side.
 *
 * @details The assembly has two stages:
 *
 * **1. Volume term** — for each element:
 *      integral of grad(phi_p_j) . phi_v_i  over the element,
 * accumulated as (*mat)(v_dof, p_dof) += coeff and secmem(elem, v_dof) -= coeff * p(elem, p_dof).
 *
 * **2. Internal face term** — for each internal face shared by elem0 and elem1:
 *   The average-jump coupling integral of {{phi_p}} * [phi_v . n] is expanded into
 *   four pointwise products at face quadrature points:
 *    - coeff00: -0.5 * phi_p0 * n_d * phi_v0  (elem0 pressure, elem0 velocity)
 *    - coeff01: +0.5 * phi_p1 * n_d * phi_v0  (elem1 pressure, elem0 velocity)
 *    - coeff10: -0.5 * phi_p0 * n_d * phi_v1  (elem0 pressure, elem1 velocity)
 *    - coeff11: +0.5 * phi_p1 * n_d * phi_v1  (elem1 pressure, elem1 velocity)
 *
 *   The sign convention follows the outward normal of elem0: the jump [v.n] on the
 *   face is (v0 - v1).n/|f|, hence the minus sign on elem0-side contributions.
 *
 * @param matrices  Map of matrix name → Matrice_Morse pointer to accumulate into.
 * @param secmem    Right-hand side (momentum residual) to accumulate into.
 * @param semi_impl Map of semi-implicit field values; if "pression" is present,
 *                  its values are used instead of the current pressure field.
 */
void Op_Grad_DG::ajouter_blocs(matrices_t matrices, DoubleTab& secmem, const tabs_t& semi_impl) const
{
 
  const DoubleTab& inco_p = semi_impl.count("pression") ? semi_impl.at("pression") :  ref_cast(Navier_Stokes_std, equation()).pression().valeurs(); // NB : is this working ?
  Matrice_Morse *mat = matrices.count("pression") ? matrices.at("pression") : nullptr; // pression for the stabilisation term if np==nv
 
  const Domaine_DG& domaine = le_dom_DG.valeur();
 
  int order_v = Option_DG::Get_order_for("vitesse");
  int order_p = Option_DG::Get_order_for("pression");
 
  const BasisFunction& bfunc_v = domaine.get_basisFunction(order_v);
  const int nb_bfunc_v = bfunc_v.nb_bfunc();
 
  const BasisFunction& bfunc_p = domaine.get_basisFunction(order_p);
  const int nb_bfunc_p = bfunc_p.nb_bfunc();
 
  const int dim = Objet_U::dimension;
  const IntTab& indices_glob_elem_v = bfunc_v.indices_glob_elem(dim);
  const IntTab& indices_glob_elem_p = bfunc_p.indices_glob_elem();
 
  const int quad_order = bfunc_p.get_default_quadrature_order(); //TODO DG should we choose the max or the p order quadrature ?
  const Quadrature_base& quad = domaine.get_quadrature(quad_order);  // Same quadrature for all champs
 
 
  int nb_pts_integ_max = quad.nb_pts_integ_max();
  double coeff;
  DoubleTab grad_fbase_elem(nb_bfunc_p, nb_pts_integ_max, Objet_U::dimension);
  DoubleTab f_base_v(nb_bfunc_v, nb_pts_integ_max);
  DoubleTab scalar_product_dim(nb_pts_integ_max);
 
  // Loop over elements to compute \int q_h div(u_h) dV
  for (int elem = 0; elem < domaine.nb_elem(); elem++)
    {
      int ind_elem_v = indices_glob_elem_v(elem);
      int ind_elem_p = indices_glob_elem_p(elem);
      bfunc_p.eval_grad_bfunc(quad, elem, grad_fbase_elem);
      bfunc_v.eval_bfunc(quad, elem, f_base_v);
      for (int d = 0; d < dim; d++)
        for (int velocity_index = 0; velocity_index < nb_bfunc_v; velocity_index++)
          for (int pressure_index = 0; pressure_index < nb_bfunc_p; pressure_index++)
            {
              for (int k = 0; k < quad.nb_pts_integ(elem); k++)
                scalar_product_dim(k) = grad_fbase_elem(pressure_index, k, d) * f_base_v(velocity_index, k);
              coeff = quad.compute_integral_on_elem(elem, scalar_product_dim);
              if (mat)
                (*mat)(ind_elem_v + velocity_index + d * nb_bfunc_v, ind_elem_p + pressure_index) += coeff;
              secmem(elem, velocity_index + d * nb_bfunc_v) -= coeff * inco_p(elem, pressure_index);
            }
    }
 
  const DoubleTab& face_normales = domaine.face_normales();
  const DoubleVect& face_surfaces = domaine.face_surfaces();
  int nb_pts_int_fac = quad.nb_pts_integ_facets();
  const IntTab& face_voisins = domaine.face_voisins();
 
  double coeff00, coeff10, coeff01, coeff11;
 
  DoubleTab eval_jump_on_facet00(nb_pts_int_fac);
  DoubleTab eval_jump_on_facet01(nb_pts_int_fac);
  DoubleTab eval_jump_on_facet10(nb_pts_int_fac);
  DoubleTab eval_jump_on_facet11(nb_pts_int_fac);
 
  DoubleTab f_base_v0(nb_bfunc_v, nb_pts_int_fac);
  DoubleTab f_base_v1(nb_bfunc_v, nb_pts_int_fac);
  DoubleTab f_base_p0(nb_bfunc_p, nb_pts_int_fac);
  DoubleTab f_base_p1(nb_bfunc_p, nb_pts_int_fac);
 
  int premiere_face_int = domaine.premiere_face_int();
 
  // Loop over facets to compute \int_f [u_h.n]_F {{q_h}} dS
  for (int face = premiere_face_int; face < domaine.nb_faces(); face++)
    {
      int elem0 = face_voisins(face,0);
      int elem1 = face_voisins(face,1);
      double sur_f = face_surfaces(face);
      int ind_elem0_v = indices_glob_elem_v(elem0);
      int ind_elem1_v = indices_glob_elem_v(elem1);
      int ind_elem0_p = indices_glob_elem_p(elem0);
      int ind_elem1_p = indices_glob_elem_p(elem1);
      bfunc_v.eval_bfunc_on_facets(quad, elem0, face, f_base_v0);
      bfunc_v.eval_bfunc_on_facets(quad, elem1, face, f_base_v1);
      bfunc_p.eval_bfunc_on_facets(quad, elem0, face, f_base_p0);
      bfunc_p.eval_bfunc_on_facets(quad, elem1, face, f_base_p1);
      for (int d = 0; d < Objet_U::dimension; d++)
        {
          for (int velocity_index = 0; velocity_index < nb_bfunc_v; velocity_index++)
            {
              for (int pressure_index = 0; pressure_index < nb_bfunc_p; pressure_index++)
                {
                  for (int k = 0; k < quad.nb_pts_integ_facets(); k++)
                    {
                      eval_jump_on_facet00(k) = -f_base_p0(pressure_index, k) * face_normales(face, d)  * 0.5 * f_base_v0(velocity_index, k) / sur_f;
                      eval_jump_on_facet01(k) = +f_base_p1(pressure_index, k) * face_normales(face, d)  * 0.5 * f_base_v0(velocity_index, k) / sur_f;
                      eval_jump_on_facet10(k) = -f_base_p0(pressure_index, k) * face_normales(face, d)  * 0.5 * f_base_v1(velocity_index, k) / sur_f;
                      eval_jump_on_facet11(k) = +f_base_p1(pressure_index, k) * face_normales(face, d)  * 0.5 * f_base_v1(velocity_index, k) / sur_f;
                    }
                  coeff00 = quad.compute_integral_on_facet(face, eval_jump_on_facet00);
                  coeff01 = quad.compute_integral_on_facet(face, eval_jump_on_facet01);
                  coeff10 = quad.compute_integral_on_facet(face, eval_jump_on_facet10);
                  coeff11 = quad.compute_integral_on_facet(face, eval_jump_on_facet11);
 
                  if (mat)
                    {
                      (*mat)(ind_elem0_v + velocity_index + d * nb_bfunc_v, ind_elem0_p + pressure_index) += coeff00;
                      (*mat)(ind_elem0_v + velocity_index + d * nb_bfunc_v, ind_elem1_p + pressure_index) += coeff01;
                      (*mat)(ind_elem1_v + velocity_index + d * nb_bfunc_v, ind_elem0_p + pressure_index) += coeff10;
                      (*mat)(ind_elem1_v + velocity_index + d * nb_bfunc_v, ind_elem1_p + pressure_index) += coeff11;
                    }
                  secmem(elem0, velocity_index + d * nb_bfunc_v) -= coeff00 * inco_p(elem0, pressure_index);
                  secmem(elem0, velocity_index + d * nb_bfunc_v) -= coeff01 * inco_p(elem1, pressure_index);
                  secmem(elem1, velocity_index + d * nb_bfunc_v) -= coeff10 * inco_p(elem0, pressure_index);
                  secmem(elem1, velocity_index + d * nb_bfunc_v) -= coeff11 * inco_p(elem1, pressure_index);
                }
            }
        }
    }
}
 
DoubleTab& Op_Grad_DG::calculer(const DoubleTab& pressure, DoubleTab& grad) const
{
  grad = 0.;
  return ajouter(pressure, grad);
}
 
 
int Op_Grad_DG::impr(Sortie& os) const
{
  return 0;
}