Op_Evanescence_Homogene_Elem_base.cpp

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#include <Op_Evanescence_Homogene_Elem_base.h>
#include <Schema_Implicite_base.h>
#include <Champ_Inc_P0_base.h>
#include <Milieu_composite.h>
#include <Champ_Uniforme.h>
#include <Pb_Multiphase.h>
#include <Matrix_tools.h>
#include <Domaine_VF.h>
#include <Param.h>
#include <SETS.h>
 
 
Implemente_base(Op_Evanescence_Homogene_Elem_base,"Op_Evanescence_Homogene_Elem_base",Operateur_Evanescence_base);
 
Sortie& Op_Evanescence_Homogene_Elem_base::printOn(Sortie& os) const { return os; }
 
Entree& Op_Evanescence_Homogene_Elem_base::readOn(Entree& is)
{
  Param param(que_suis_je());
  param.ajouter("alpha_res", &alpha_res_, Param::REQUIRED);
  param.ajouter("alpha_res_min", &alpha_res_min_);
  param.lire_avec_accolades_depuis(is);
  return is;
}
 
void Op_Evanescence_Homogene_Elem_base::dimensionner_blocs(matrices_t matrices, const tabs_t& semi_impl) const
{
  const Domaine_VF& domaine = ref_cast(Domaine_VF, equation().domaine_dis());
  const DoubleTab& inco = equation().inconnue().valeurs();
 
  /* must be able to add / subtract equations between components */
  int i, e, n, N = inco.line_size();
  if (N == 1) return; //no evanescence in single-phase flow!
  for (auto &&n_m : matrices)
    if (n_m.second->nb_colonnes())
      {
        Matrice_Morse& mat = *n_m.second, mat2;
        Stencil sten(0, 2);
 
 
        std::set<int> idx;
        for (e = 0; e < domaine.nb_elem(); e++, idx.clear())
          {
            for (i = N * e, n = 0; n < N; n++, i++)
              for (auto j = mat.get_tab1()(i) - 1; j < mat.get_tab1()(i + 1) - 1; j++)
                idx.insert(mat.get_tab2()(j) - 1);
            for (i = N * e, n = 0; n < N; n++, i++)
              for (auto &&c : idx) sten.append_line(i, c);
          }
        Matrix_tools::allocate_morse_matrix(mat.nb_lignes(), mat.nb_colonnes(), sten, mat2);
        mat = mat2; //to force the coefficient ordering in the matrix (speeds up row-by-row operations)
      }
}
 
void Op_Evanescence_Homogene_Elem_base::ajouter_blocs(matrices_t matrices, DoubleTab& secmem, const tabs_t& semi_impl) const
{
  const Milieu_composite& milc = ref_cast(Milieu_composite, equation().milieu());
  const Champ_Inc_P0_base& ch = ref_cast(Champ_Inc_P0_base, equation().inconnue());
  const Domaine_VF& domaine = ref_cast(Domaine_VF, equation().domaine_dis());
  const Pb_Multiphase& pb = ref_cast(Pb_Multiphase, equation().probleme());
  const DoubleTab& inco = ch.valeurs(), &alpha = pb.equation_masse().inconnue().valeurs(), &rho = equation().milieu().masse_volumique().valeurs(), &p = ref_cast(QDM_Multiphase, pb.equation_qdm()).pression().valeurs();
 
  const SETS *sch = sub_type(Schema_Implicite_base, pb.equation_qdm().schema_temps()) && sub_type(SETS, ref_cast(Schema_Implicite_base, pb.equation_qdm().schema_temps()).solveur().valeur())
                    ? &ref_cast(SETS, ref_cast(Schema_Implicite_base, pb.equation_qdm().schema_temps()).solveur().valeur()) : nullptr;
 
  int e, k, n, N = inco.line_size(), m, M = p.line_size(), is_m = ch.le_nom() == "alpha", cR = (rho.dimension_tot(0) == 1),
               iter = sch ? sch->iteration_ : 0, p_degen = is_m && sch ? sch->p_degen_ : 0;
  if (N == 1 || p_degen || (is_m && !iter)) return; //no evanescence in single-phase or if p is degenerate
 
  double a_eps = alpha_res_, a_eps_min = alpha_res_min_, a_m, a_max; //threshold triggering the evanescence treatment
 
  /* recherche de phases evanescentes et traitement des seconds membres */
  IntTrav maj(inco.dimension_tot(0)); //maj(i): majority phase of row i
  DoubleTrav coeff(inco.dimension_tot(0), inco.line_size(), 2); //coeff(i, n, 0/1): coefficient applied to the existing equation / to the eq. "inco = v_maj", and their derivatives w.r.t. alpha
  Matrice_Morse& mat_diag = *matrices.at(ch.le_nom().getString());
  for (e = 0; e < domaine.nb_elem(); e++)
    {
      /* phase majoritaire */
      for (a_max = 0, k = -1, n = 0; n < N; n++)
        if ((a_m = alpha(e, n)) > a_max) k = n, a_max = a_m;
      if (k >= 0) maj(e) = k;
      else abort();
 
      /* coeff d'evanescence, second membre */
      for (n = 0, m = 0; n < N; n++, m += (M > 1))
        if (n != k && (a_m = alpha(e, n)) < a_eps)
          {
            double val = is_m ? 0 : milc.has_saturation(n, k) ? milc.get_saturation(n, k).Tsat(p(e, m)) : inco(e, k); //target value to which inco(e, n) is relaxed
            coeff(e, n, 0) = (a_eps == a_eps_min ? (a_m < a_eps) : std::min(std::max((a_eps - a_m) / (a_eps - a_eps_min), 0.), 1.));
            coeff(e, n, 1) = mat_diag(N * e + k, N * e + k) * coeff(e, n, 0);
            double flux = coeff(e, n, 0) * secmem(e, n) + coeff(e, n, 1) * (inco(e, n) - val);
            secmem(e, k) += (p_degen ? rho(!cR * e, k) : 1) * flux, secmem(e, n) -= (p_degen ? rho(!cR * e, n) : 1) * flux;
          }
    }
 
  /* lignes de matrices */
  for (auto &&n_m : matrices)
    if (n_m.second->nb_colonnes())
      {
        int diag = (n_m.first == ch.le_nom().getString()), press = (n_m.first == "pression"); //are we on the diagonal block, on the pressure block?
        Matrice_Morse& mat = *n_m.second;
        auto i(mat.get_tab1()(0));
        auto j(i);
        for (e = 0; e < domaine.nb_elem(); e++)
          for (n = 0, m = 0; n < N; n++, m += (M > 1))
            if (coeff(e, n, 0))
              {
                k = maj(e); //majority phase
                double dval = is_m ? 0 : milc.has_saturation(n, k) ? (press ? milc.get_saturation(n, k).dP_Tsat(p(e, m)) : 0) : diag; //derivative of val (zero if not on the right block)
                int cval = is_m ? -1 : milc.has_saturation(n, k) ? M * e + m : N * e + k; //column index associated with this derivative
                for (i = mat.get_tab1()(N * e + n) - 1, j = mat.get_tab1()(N * e + k) - 1; i < mat.get_tab1()(N * e + n + 1) - 1; i++, j++)
                  {
                    assert(mat.get_tab2()(j) == mat.get_tab2()(i));
                    int c = mat.get_tab2()(i) - 1; //column index (common to both rows thanks to dimensionner_blocs())
                    double dflux = -coeff(e, n, 0) * mat.get_set_coeff()(i) + coeff(e, n, 1) * (diag * (c == N * e + n) - dval * (c == cval)); //derivative of flux w.r.t. secmem, inco, val
                    mat.get_set_coeff()(i) += (p_degen ? rho(!cR * e, n) : 1) * dflux;
                    mat.get_set_coeff()(j) -= (p_degen ? rho(!cR * e, k) : 1) * dflux;
                  }
              }
      }
}