Op_Diff_PolyMAC_CDO_base.cpp

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#include <Modele_turbulence_scal_base.h>
#include <Echange_externe_impose.h>
#include <Op_Diff_PolyMAC_CDO_base.h>
#include <Check_espace_virtuel.h>
#include <Champ_Elem_PolyMAC_CDO.h>
#include <Champ_Fonc_P0_base.h>
#include <Domaine_Cl_PolyMAC_family.h>
#include <Champ_Uniforme.h>
#include <Milieu_base.h>
 
Implemente_base(Op_Diff_PolyMAC_CDO_base, "Op_Diff_PolyMAC_CDO_base", Op_Diff_PolyMAC_CDO_Gen_base);
 
Sortie& Op_Diff_PolyMAC_CDO_base::printOn(Sortie& s) const { return s << que_suis_je(); }
 
Entree& Op_Diff_PolyMAC_CDO_base::readOn(Entree& s) { return s; }
 
double Op_Diff_PolyMAC_CDO_base::calculer_dt_stab() const
{
  update_nu();
  const Domaine& mon_dom = le_dom_poly_->domaine();
  double dt_stab = DMAXFLOAT;
 
  const int nb_elem = mon_dom.nb_elem();
 
  if (!has_champ_masse_volumique())
    {
      // "Standard" method for computing the time step
      // This computation is very conservative: if the max of the diffusivity
      // is not reached at the location where the min of delta_h_carre is reached,
      // the time step is underestimated.
      const Champ_base& champ_diffusivite = diffusivite_pour_pas_de_temps();
      const DoubleVect& valeurs_diffusivite = champ_diffusivite.valeurs();
      double alpha_max = local_max_vect(valeurs_diffusivite);
 
      // Detect if a heat flux is imposed on a boundary through Paroi_echange_externe_impose keyword
      double h_imp_max = -1, h_imp_temp = -2;
 
      const Domaine_Cl_PolyMAC_family& le_dom_cl_poly = la_zcl_poly_.valeur();
      for (int i = 0; i < le_dom_cl_poly.nb_cond_lim(); i++)
        {
          // loop on boundaries
          const Cond_lim_base& la_cl = le_dom_cl_poly.les_conditions_limites(i).valeur();
 
          if (sub_type(Echange_externe_impose, la_cl))
            {
              const Echange_externe_impose& la_cl_int = ref_cast(Echange_externe_impose, la_cl);
              const Champ_front_base& le_ch_front = ref_cast(Champ_front_base, la_cl_int.h_imp());
              const DoubleVect& tab = le_ch_front.valeurs();
              if (tab.size() != 0)
                {
                  h_imp_temp = local_max_vect(tab); // get h_imp from datafile
                  h_imp_temp = std::fabs(h_imp_temp); // we should take the absolute value since it can be negative!
                  h_imp_max = (h_imp_temp > h_imp_max) ? h_imp_temp : h_imp_max; // Should we take the max if more than one bc has h_imp ?
                }
            }
        } // End loop on boundaries
      h_imp_max = Process::mp_max(h_imp_max);
 
      if (alpha_max != 0.0 && nb_elem != 0)
        {
          double min_delta_h_carre = le_dom_poly_->carre_pas_du_maillage();
          if (h_imp_max > 0.0)  //a heat flux is imposed on a boundary condition
            {
              // get the thermal conductivity
              const Equation_base& mon_eqn = le_dom_cl_poly.equation();
              const Milieu_base& mon_milieu = mon_eqn.milieu();
              const DoubleVect& tab_lambda = mon_milieu.conductivite().valeurs();
              double max_conductivity = local_max_vect(tab_lambda);
 
              // compute Biot number given by Bi = L*h/lambda.
              double Bi = h_imp_max * sqrt(min_delta_h_carre) / max_conductivity;
              // if Bi>1, replace conductivity by h_imp*h in diffusivity. We are very conservative since h_imp_max is not necessarily located where max_conductivity is.
              if (Bi > 1.0)
                alpha_max *= h_imp_max * sqrt(min_delta_h_carre) / max_conductivity;
            }
          dt_stab = min_delta_h_carre / (2. * dimension * alpha_max);
        }
 
    }
  else
    {
      const int deux_dim = 2 * Objet_U::dimension;
      const Champ_base& champ_diffu = diffusivite();
      const DoubleTab& valeurs_diffu = champ_diffu.valeurs();
      const Champ_base& champ_rho = get_champ_masse_volumique();
      const DoubleTab& valeurs_rho = champ_rho.valeurs();
 
      assert(sub_type(Champ_Elem_PolyMAC_CDO, champ_rho));
      assert(sub_type(Champ_Fonc_P0_base, champ_diffu));
      // assert(valeurs_rho.size_array()== mon_dom.les_elems().dimension_tot(0));
      // Champ_Elem_PolyMAC_CDO: field at elements and faces
      // Variable density field.
      const IntTab& e_f = le_dom_poly_->elem_faces();
      //Cerr << e_f << finl;
      for (int elem = 0; elem < nb_elem; elem++)
        {
          const double diffu = valeurs_diffu(elem);
          const double rho = valeurs_rho(elem);
          double dt;
          bool flag;
          if (polymac_flica5)
            {
              int nb_rf = 0;
              for (int i = 0; i < e_f.dimension(1); i++)
                if (e_f(elem, i) != -1)
                  nb_rf++;
              flag = (nb_rf == deux_dim); // to improve: this could not be a regular hexahedron...
            }
          else
            flag = (e_f.dimension(1) == deux_dim || e_f(elem, deux_dim) == -1);
          if (flag)
            {
              // VDF-type cell (deux_dim faces per element)
              // ToDo: implement for the case has_champ_masse_volumique()==false
              double h = 0;
              for (int f = 0; f < deux_dim; f++)
                {
                  int face = e_f(elem, f);
                  const double d = le_dom_poly_->volumes(elem) / le_dom_poly_->surface(face);
                  h += 0.5 / (d * d); // multiply by 0.5 since each face is counted twice
                  //Cerr << elem << " " << face << " " << le_dom_poly_->surface(face) << finl;
                }
              // See Op_Diff_VDF_Elem_base::calculer_dt_stab():
              dt = 0.5 * rho / ((diffu + DMINFLOAT) * h);
              //Cerr << "VDF " << dt << finl;
            }
          else
            {
              dt = le_dom_poly_->carre_pas_maille(elem) * rho / (deux_dim * (diffu + DMINFLOAT));
              //Cerr << "NC  " << dt << finl;
            }
          if (dt < dt_stab)
            dt_stab = dt;
        }
    }
 
  dt_stab = Process::mp_min(dt_stab);
  return dt_stab;
}
 
void Op_Diff_PolyMAC_CDO_base::completer()
{
  Operateur_base::completer();
  nu_.resize(0, equation().que_suis_je() == "Transport_K_Epsilon" ? 2 : diffusivite().valeurs().line_size());
  le_dom_poly_->domaine().creer_tableau_elements(nu_);
  le_dom_poly_->creer_tableau_faces(nu_fac_);
  nu_a_jour_ = 0;
}
 
void Op_Diff_PolyMAC_CDO_base::update_nu() const
{
  if (nu_a_jour_) return; // already done
 
  const Domaine_PolyMAC_CDO& domaine = le_dom_poly_.valeur();
  const Conds_lim& cls = la_zcl_poly_->les_conditions_limites();
  int i, j, f;
 
  /* 1. nu_ */
  //sizing
  const DoubleTab& diffu = diffusivite().valeurs();
  if (equation().que_suis_je() != "Transport_K_Epsilon")
    {
      if (!diffu.get_md_vector())
        {
          // uniform diffusivity
          int n = nu_.dimension_tot(0), nb_comp = nu_.line_size();
          // Arrays viewed as one-dimensional:
          const DoubleVect& arr_diffu = diffu;
          DoubleVect& arr_nu = nu_;
          for (i = 0; i < n; i++)
            for (j = 0; j < nb_comp; j++)
              arr_nu[i * nb_comp + j] = arr_diffu[j];
        }
      else
        {
          assert(nu_.get_md_vector() == diffu.get_md_vector());
          assert_espace_virtuel_vect(diffu);
          nu_.inject_array(diffu);
        }
    }
 
  /* add turbulent diffusivity if it exists */
  if (has_diffusivite_turbulente())
    {
      const DoubleTab& diffu_turb = diffusivite_turbulente().valeurs();
      if (equation().que_suis_je() == "Transport_K_Epsilon")
        {
          bool nu_uniforme = sub_type(Champ_Uniforme, diffusivite());
          double val_nu = diffu(0, 0);
          for (i = 0; i < diffu_turb.dimension(0); i++)
            for (j = 0; j < 2; j++)
              {
                if (!nu_uniforme)
                  val_nu = diffu(i, 0);
                nu_(i, j) = val_nu + diffu_turb(i, j);
              }
        }
      else
        {
          if (!diffu_turb.get_md_vector())
            {
              // uniform diffusivity
              int n = nu_.dimension_tot(0), nb_comp = nu_.line_size();
              // Arrays viewed as one-dimensional:
              const DoubleVect& arr_diffu_turb = diffu_turb;
              DoubleVect& arr_nu = nu_;
              for (i = 0; i < n; i++)
                for (j = 0; j < nb_comp; j++)
                  arr_nu[i * nb_comp + j] += arr_diffu_turb[j];
            }
          else
            {
              assert(nu_.get_md_vector() == diffu_turb.get_md_vector());
              assert_espace_virtuel_vect(diffu_turb);
              nu_ += diffu_turb;
            }
        }
    }
 
  /* 2. nu_fac: accounts for wall laws and the user factor (nu_fac_mod) */
  // are wall laws used?
  const RefObjU& modele_turbulence = equation().get_modele(TURBULENCE);
  int loi_par = modele_turbulence && sub_type(Modele_turbulence_scal_base, modele_turbulence.valeur()) &&
                ref_cast(Modele_turbulence_scal_base,modele_turbulence.valeur()).loi_paroi().use_equivalent_distance();
 
  for (i = 0; i <= cls.size(); i++) //loop over boundaries, then over internal faces
    {
      int deb = i < cls.size() ? ref_cast(Front_VF, cls[i]->frontiere_dis()).num_premiere_face() : domaine.premiere_face_int(), num =
                  i < cls.size() ? ref_cast(Front_VF, cls[i]->frontiere_dis()).nb_faces() : domaine.nb_faces() - domaine.premiere_face_int();
      for (f = deb; f < deb + num; f++) //nu per component at each face
        {
          if (i < cls.size() && loi_par) //multiplicative factor due to a wall law
            nu_fac_(f) = domaine.dist_norm_bord(f) / ref_cast(Modele_turbulence_scal_base,modele_turbulence.valeur()).loi_paroi().equivalent_distance(i, f - deb);
          else
            nu_fac_(f) = equation().milieu().porosite_face(f); //default: factor due to porosity
          if (nu_fac_mod.size())
            nu_fac_(f) *= nu_fac_mod(f); //account for nu_fac_mod
        }
    }
  nu_fac_.echange_espace_virtuel();
  nu_a_jour_ = 1;
}