Op_Dift_VEF_base.cpp

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#include <Modele_turbulence_scal_base.h>
#include <Modele_turbulence_hyd_base.h>
#include <Navier_Stokes_std.h>
#include <Op_Dift_VEF_base.h>
#include <Domaine_Cl_VEF.h>
 
 
Implemente_base(Op_Dift_VEF_base, "Op_Dift_VEF_base", Op_Diff_VEF_base);
 
Sortie& Op_Dift_VEF_base::printOn(Sortie& is) const { return Op_Diff_VEF_base::printOn(is); }
 
Entree& Op_Dift_VEF_base::readOn(Entree& is) { return Op_Diff_VEF_base::readOn(is); }
 
void Op_Dift_VEF_base::associer_modele_turbulence(const Modele_turbulence_hyd_base& mod)
{
  le_modele_turbulence = mod;
}
 
void Op_Dift_VEF_base::mettre_a_jour(double)
{
  if (sub_type(Navier_Stokes_std, equation())) // process the hydraulics equation
    {
      if (le_modele_turbulence->utiliser_loi_paroi())
        {
          // BM: only take the reference if the array has been initialised, otherwise it blocks initialisation
          const DoubleTab& tab = le_modele_turbulence->loi_paroi().Cisaillement_paroi();
          if (tab.size_array() > 0) tau_tan_.ref(tab);
        }
    }
}
 
void Op_Dift_VEF_base::associer(const Domaine_dis_base& domaine_dis, const Domaine_Cl_dis_base& domaine_cl_dis, const Champ_Inc_base& ch_transporte)
{
  le_dom_vef = ref_cast(Domaine_VEF, domaine_dis);
  la_zcl_vef = ref_cast(Domaine_Cl_VEF, domaine_cl_dis);
  inconnue_ = ch_transporte;
}
 
void Op_Dift_VEF_base::completer()
{
  Operateur_base::completer();
 
  const RefObjU& modele_turbulence = equation().get_modele(TURBULENCE);
  if (modele_turbulence && sub_type(Modele_turbulence_hyd_base, modele_turbulence.valeur()))
    {
      const Modele_turbulence_hyd_base& mod_turb = ref_cast(Modele_turbulence_hyd_base, modele_turbulence.valeur());
      const Champ_Fonc_base& viscosite_turbulente = mod_turb.viscosite_turbulente();
      associer_diffusivite_turbulente(viscosite_turbulente);
      associer_modele_turbulence(mod_turb);
    }
  else if (sub_type(Modele_turbulence_scal_base, modele_turbulence.valeur()))
    {
      const Modele_turbulence_scal_base& modele_turbulence_scalaire = ref_cast(Modele_turbulence_scal_base, modele_turbulence.valeur());
      const Champ_Fonc_base& conductivite_turbulente = modele_turbulence_scalaire.conductivite_turbulente();
      associer_diffusivite_turbulente(conductivite_turbulente);
    }
  else
    {
      Cerr << "Error in Op_Dift_VEF_base::completer() " << finl;
      Cerr << que_suis_je() << " operator is presently associated to " << equation().que_suis_je() << finl;
      Cerr << "instead of being associated to an equation dedicated to a turbulent flow." << finl;
      Process::exit();
    }
}
 
void Op_Dift_VEF_base::calculer_borne_locale(DoubleVect& tab_borne_visco_turb, double dt_conv, double dt_diff_sur_dt_conv) const
{
  const Domaine_VEF& le_dom_VEF = domaine_vef();
  int nb_elem = le_dom_VEF.nb_elem();
  int flag = diffusivite().valeurs().dimension(0) > 1 ? 1 : 0;
  const double dim = Objet_U::dimension;
  CDoubleTabView diffu = diffusivite().valeurs().view_ro();
  CDoubleArrView carre_pas_maille = le_dom_VEF.carre_pas_maille().view_ro();
  DoubleArrView borne_visco_turb = tab_borne_visco_turb.view_rw();
  Kokkos::parallel_for(start_gpu_timer(__KERNEL_NAME__), nb_elem, KOKKOS_LAMBDA(const int elem)
  {
    double h_inv = 1. / carre_pas_maille(elem);
    // Not the cleanest way to retrieve diffu, but avoids code duplication across multiple classes:
    double diffu_elem = (flag ? diffu(elem, 0) : diffu(0, 0));
    double coef = 1. / (2 * (dt_conv + DMINFLOAT) * dim * h_inv * dt_diff_sur_dt_conv) - diffu_elem;
    if (coef > 0 && coef < borne_visco_turb(elem))
      borne_visco_turb(elem) = coef;
  });
  end_gpu_timer(__KERNEL_NAME__);
}
 
// The diffusivity is constant per element, so dt_diff must be computed per element: dt_stab=Min(dt_diff(K) = h(K)*h(K)/(2*dimension*diffu2_(K)))
// where diffu2_ is the sum of the laminar and turbulent diffusivities.
 
//GF: alpha_dt_stab=(alpha+alpha_t)*alpha_dt_stab/alpha AND alpha_dt_stab=(nu+diff_nu_turb)*valeurs_diffusivite_dt/nu
double Op_Dift_VEF_base::calculer_dt_stab() const
{
  remplir_nu(nu_); // Fill nu with the diffusivity at each element
 
  //DoubleVect tab_diffu_turb(diffusivite_turbulente().valeurs());
  DoubleTrav tab_diffu_turb;
  tab_diffu_turb = diffusivite_turbulente().valeurs();
  DoubleTrav tab_diffu;
  tab_diffu = nu_; // XXX: Elie Saikali: Warning - not the same as DoubleTrav diffu(nu_) !!!!!!!!!
 
  if (equation().que_suis_je().debute_par("Convection_Diffusion_Temp"))
    {
      double rhocp = mon_equation->domaine_dis().nb_elem() > 0 ?  mon_equation->milieu().capacite_calorifique().valeurs()(0, 0) * mon_equation->milieu().masse_volumique().valeurs()(0, 0) : 1.0;
      tab_diffu_turb /= rhocp;
      tab_diffu /= rhocp;
    }
 
  const double deux_dim = 2. * Objet_U::dimension;
  const Domaine_VEF& le_dom_VEF = domaine_vef();
  const int le_dom_nb_elem = le_dom_VEF.domaine().nb_elem();
  double dt_stab = 1.e30;
  CDoubleTabView diffu = tab_diffu.view_ro();
  CDoubleArrView diffu_turb = static_cast<const DoubleVect&>(tab_diffu_turb).view_ro();
  CDoubleArrView carre_pas_maille = le_dom_VEF.carre_pas_maille().view_ro();
  if (has_champ_masse_volumique())
    {
      const DoubleTab& tab_rho_elem = get_champ_masse_volumique().valeurs();
      assert(tab_rho_elem.size_array() == le_dom_VEF.nb_elem_tot());
      CDoubleArrView rho_elem = static_cast<const DoubleVect&>(tab_rho_elem).view_ro();
      Kokkos::parallel_reduce(start_gpu_timer(__KERNEL_NAME__),
                              Kokkos::RangePolicy<>(0, le_dom_nb_elem), KOKKOS_LAMBDA(
                                const int num_elem, double& dtstab)
      {
        double alpha = diffu(num_elem, 0) + diffu_turb(num_elem); // PQ : 06/03
        alpha /= rho_elem(num_elem);
        double coef = carre_pas_maille(num_elem) / (deux_dim * (alpha + DMINFLOAT));
        if (coef < dtstab) dtstab = coef;
      }, Kokkos::Min<double>(dt_stab));
    }
  else
    {
      const DoubleTab& tab_valeurs_diffusivite = diffusivite_pour_pas_de_temps().valeurs();
      const int nb_comp = tab_valeurs_diffusivite.line_size(), cD = (tab_valeurs_diffusivite.dimension(0) == 1); // uniform or not?
      CDoubleTabView valeurs_diffusivite = tab_valeurs_diffusivite.view_ro();
      Kokkos::parallel_reduce(start_gpu_timer(__KERNEL_NAME__),
                              Kokkos::RangePolicy<>(0, le_dom_nb_elem), KOKKOS_LAMBDA(
                                const int num_elem, double& dtstab)
      {
        for (int nc = 0; nc < nb_comp; nc++)
          {
            double alpha = diffu(num_elem, nc) + diffu_turb(num_elem);
            const double valeurs_diffusivite_dt = valeurs_diffusivite(!cD * num_elem, nc);
            alpha *= valeurs_diffusivite_dt / (diffu(num_elem, nc) + DMINFLOAT);
            double coef = carre_pas_maille(num_elem) / (deux_dim * (alpha + DMINFLOAT));
            if (coef < dtstab) dtstab = coef;
          }
      }, Kokkos::Min<double>(dt_stab));
    }
  end_gpu_timer(__KERNEL_NAME__);
  dt_stab = Process::mp_min(dt_stab);
  return dt_stab;
}
 
// See Op_Dift_VEF_Face::calculer_dt_stab() for the dt_stab computation strategy
void Op_Dift_VEF_base::calculer_pour_post(Champ_base& espace_stockage, const Nom& option, int comp) const
{
  if (Motcle(option) == "stabilite")
    {
      DoubleTab& es_valeurs = espace_stockage.valeurs();
 
      if (le_dom_vef)
        {
          remplir_nu(nu_); // Fill nu with the diffusivity at each element
 
          const Domaine_VEF& le_dom_VEF = domaine_vef();
          const Domaine& le_dom = le_dom_VEF.domaine();
          const DoubleVect& diffu_turb = diffusivite_turbulente().valeurs();
          double alpha = -123., coef = -123.;
          ToDo_Kokkos("critical");
 
          int le_dom_nb_elem = le_dom.nb_elem();
          if (has_champ_masse_volumique())
            {
              const DoubleTab& rho_elem = get_champ_masse_volumique().valeurs();
              assert(rho_elem.size_array() == le_dom_VEF.nb_elem_tot());
              for (int num_elem = 0; num_elem < le_dom_nb_elem; num_elem++)
                {
                  alpha = nu_[num_elem] + diffu_turb[num_elem]; // PQ : 06/03
                  alpha /= rho_elem[num_elem];
                  coef = le_dom_VEF.carre_pas_maille()(num_elem) / (2. * dimension * alpha);
                  es_valeurs(num_elem) = coef;
                }
            }
          else
            {
              const Champ_base& champ_diffusivite = diffusivite_pour_pas_de_temps();
              const DoubleTab& valeurs_diffusivite = champ_diffusivite.valeurs();
              const int cD = (valeurs_diffusivite.dimension(0) == 1); // uniform or not?
              for (int num_elem = 0; num_elem < le_dom_nb_elem; num_elem++)
                {
                  const double valeurs_diffusivite_dt = valeurs_diffusivite(!cD * num_elem);
                  alpha = nu_[num_elem] + diffu_turb[num_elem]; // PQ : 06/03
                  alpha *= valeurs_diffusivite_dt / nu_[num_elem];
                  coef = le_dom_VEF.carre_pas_maille()(num_elem) / (2. * dimension * alpha);
                  es_valeurs(num_elem) = coef;
                }
            }
 
          assert(est_egal(mp_min_vect(es_valeurs), calculer_dt_stab()));
        }
    }
  else
    Op_Diff_VEF_base::calculer_pour_post(espace_stockage, option, comp);
}
 
// The diffusivity is constant per element, so dt_diff must be computed per element: dt_stab=Min(dt_diff(K) = h(K)*h(K)/(2*dimension*diffu2_(K)))
// where diffu2_ is the sum of the laminar and turbulent diffusivities.
double Op_Dift_VEF_base::calculer_dt_stab_P1NCP1B() const
{
  const Domaine_VEF& domaine_VEF = domaine_vef();
  const IntTab& elem_faces = domaine_VEF.elem_faces();
  const DoubleTab& face_normales = domaine_VEF.face_normales();
  const DoubleVect& volumes = domaine_VEF.volumes(), &diffu_turb = diffusivite_turbulente().valeurs();
  const int nb_faces_elem = domaine_VEF.domaine().nb_faces_elem(), le_dom_nb_elem = domaine_VEF.domaine().nb_elem();
 
  const double diffu = diffusivite(0);
  double dt_stab = 1.e30, coef, diffu2_;
  ToDo_Kokkos("critical");
 
  for (int num_elem = 0; num_elem < le_dom_nb_elem; num_elem++)
    {
      double surf_max = 1.e-30;
      for (int i = 0; i < nb_faces_elem; i++)
        {
          const int num_face = elem_faces(num_elem, i);
          double surf = face_normales(num_face, 0) * face_normales(num_face, 0);
          for (int j = 1; j < dimension; j++)
            surf += face_normales(num_face, j) * face_normales(num_face, j);
          surf_max = (surf > surf_max) ? surf : surf_max;
        }
      double vol = volumes(num_elem);
      vol *= vol / surf_max;
      diffu2_ = diffu + diffu_turb[num_elem];
      coef = vol / (2. * dimension * (diffu2_ + DMINFLOAT));
      dt_stab = (coef < dt_stab) ? coef : dt_stab;
    }
 
  return Process::mp_min(dt_stab);
}