Op_Diff_VEF_base.cpp

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#include <Op_Diff_VEF_base.h>
#include <Champ_P1NC.h>
#include <Champ_Q1NC.h>
#include <Champ_Uniforme.h>
#include <Milieu_base.h>
#include <Probleme_base.h>
#include <Schema_Temps_base.h>
#include <Champ_Fonc_P0_base.h>
#include <Discretisation_base.h>
#include <Check_espace_virtuel.h>
#include <Echange_externe_impose.h>
 
Implemente_base(Op_Diff_VEF_base,"Op_Diff_VEF_base",Operateur_Diff_base);
 
Sortie& Op_Diff_VEF_base::printOn(Sortie& s ) const
{
  return s << que_suis_je() ;
}
 
Entree& Op_Diff_VEF_base::readOn(Entree& s )
{
  return s ;
}
 
 
/*! @brief Determine whether to compute div(phi nu grad Psi) or div(nu grad Phi psi).
 *
 */
int Op_Diff_VEF_base::phi_psi_diffuse(const Equation_base& eq) const
{
  if (eq.inconnue().le_nom()=="vitesse")
    return 1;
  return 0;
}
 
int Op_Diff_VEF_base::impr(Sortie& os) const
{
  return Op_VEF_Face::impr(os, *this);
}
 
void Op_Diff_VEF_base::associer(const Domaine_dis_base& domaine_dis,
                                const Domaine_Cl_dis_base& domaine_cl_dis,
                                const Champ_Inc_base& ch_transporte)
{
 
  const Domaine_VEF& zvef = ref_cast(Domaine_VEF,domaine_dis);
  const Domaine_Cl_VEF& zclvef = ref_cast(Domaine_Cl_VEF,domaine_cl_dis);
 
  if (sub_type(Champ_P1NC,ch_transporte))
    {
      const Champ_P1NC& inco = ref_cast(Champ_P1NC,ch_transporte);
      OBS_PTR(Champ_P1NC) inconnue;
      inconnue = inco;
    }
  if (sub_type(Champ_Q1NC,ch_transporte))
    {
      const Champ_Q1NC& inco = ref_cast(Champ_Q1NC,ch_transporte);
      OBS_PTR(Champ_Q1NC) inconnue;
      inconnue = inco;
    }
 
  le_dom_vef = zvef;
  la_zcl_vef = zclvef;
 
 
  const Domaine_VEF& domaine_VEF = le_dom_vef.valeur();
  int nb_dim = ch_transporte.valeurs().nb_dim();
  int nb_comp = 1;
 
  if(nb_dim==2)
    nb_comp = ch_transporte.valeurs().dimension(1);
 
  flux_bords_.resize(domaine_VEF.nb_faces_bord(), nb_comp);
  flux_bords_ = 0.;
}
double Op_Diff_VEF_base::calculer_dt_stab() const
{
  remplir_nu(nu_);
  // The diffusivity is constant in the domain, hence
  //
  //          dt_diff = h*h/diffusivity
 
  double dt_stab = DMAXFLOAT;
  const Domaine_VEF& domaine_VEF = le_dom_vef.valeur();
  if (!has_champ_masse_volumique())
    {
      // "Standard" method for time step computation.
      // This computation is very conservative: if the diffusivity maximum
      // is not reached at the location where the minimum of delta_h_squared 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, max_conductivity = 0;
      const Domaine_Cl_VEF& le_dom_cl_vef = la_zcl_vef.valeur();
      const Equation_base& mon_eqn = le_dom_cl_vef.equation();
 
      for(int i=0; i<le_dom_cl_vef.nb_cond_lim(); i++)
        {
          // loop on boundaries
          const Cond_lim_base& la_cl = le_dom_cl_vef.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.)||(domaine_VEF.nb_elem()==0))
        dt_stab = DMAXFLOAT;
      else
        {
          const double min_delta_h_carre = domaine_VEF.carre_pas_du_maillage();
          if (h_imp_max>0.0) //we have a BC with Paroi_echange_externe_impose
            {
              // get the thermal conductivity
              const Milieu_base& mon_milieu = mon_eqn.milieu();
              const DoubleVect& tab_lambda = mon_milieu.conductivite().valeurs();
              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
    {
      // Variable mass density field.
      const double deux_dim = 2. * Objet_U::dimension;
      const Champ_base& champ_diffu = diffusivite();
      const Champ_base& champ_rho = get_champ_masse_volumique();
      assert(sub_type(Champ_Fonc_P0_base, champ_rho));
      assert(sub_type(Champ_Fonc_P0_base, champ_diffu));
      const int nb_elem = domaine_VEF.nb_elem();
      CDoubleArrView carre_pas_maille = domaine_VEF.carre_pas_maille().view_ro();
      CDoubleArrView valeurs_diffu = static_cast<const DoubleVect&>(champ_diffu.valeurs()).view_ro();
      CDoubleArrView valeurs_rho   = static_cast<const DoubleVect&>(champ_rho.valeurs()).view_ro();
      Kokkos::parallel_reduce(start_gpu_timer(__KERNEL_NAME__),
                              range_1D(0, nb_elem), KOKKOS_LAMBDA(
                                const int elem, double& dtstab)
      {
        const double h_carre = carre_pas_maille(elem);
        const double diffu   = valeurs_diffu(elem);
        const double rho     = valeurs_rho(elem);
        const double dt      = h_carre * rho / (deux_dim * (diffu+DMINFLOAT));
        if (dt < dtstab) dtstab = dt;
      }, Kokkos::Min<double>(dt_stab));
      end_gpu_timer(__KERNEL_NAME__);
    }
  dt_stab = Process::mp_min(dt_stab);
  return dt_stab;
}
 
// cf Op_Diff_VEF_base::calculer_dt_stab() for the choice of dt_stab computation
void Op_Diff_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_);
          const Domaine_VEF& domaine_VEF = le_dom_vef.valeur();
          if (! has_champ_masse_volumique())
            {
 
              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);
 
              if ((alpha_max == 0.)||(domaine_VEF.nb_elem()==0))
                es_valeurs = DMAXFLOAT;
              else
                {
                  const int nb_elem = domaine_VEF.nb_elem();
                  for (int elem = 0; elem < nb_elem; elem++)
                    {
                      es_valeurs(elem) = domaine_VEF.carre_pas_maille()(elem) / (2. * dimension * alpha_max);
                    }
                }
            }
          else
            {
              const double           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_Fonc_P0_base, champ_rho));
              assert(sub_type(Champ_Fonc_P0_base, champ_diffu));
              const int nb_elem = domaine_VEF.nb_elem();
              assert(valeurs_rho.size_array()==domaine_VEF.nb_elem_tot());
              // Variable mass density field.
              for (int elem = 0; elem < nb_elem; elem++)
                {
                  const double h_carre = domaine_VEF.carre_pas_maille()(elem);
                  const double diffu   = valeurs_diffu(elem);
                  const double rho     = valeurs_rho(elem);
                  const double dt      = h_carre * rho / (deux_dim * diffu);
                  es_valeurs(elem) = dt;
                }
            }
 
          assert(mp_min_vect(es_valeurs)==calculer_dt_stab());
        }
    }
  else
    Operateur_Diff_base::calculer_pour_post(espace_stockage,option,comp);
}
 
Motcle Op_Diff_VEF_base::get_localisation_pour_post(const Nom& option) const
{
  Motcle loc;
  if (Motcle(option)=="stabilite")
    loc = "elem";
  else
    return Operateur_Diff_base::get_localisation_pour_post(option);
  return loc;
}
 
void Op_Diff_VEF_base::remplir_nu(DoubleTab& tab_nu) const
{
  const Domaine_VEF& domaine_VEF = le_dom_vef.valeur();
  // Size/initialize nu
  const DoubleTab& tab_diffu = diffusivite().valeurs();
  if (!tab_nu.get_md_vector())
    {
      tab_nu.resize(0, tab_diffu.line_size());
      domaine_VEF.domaine().creer_tableau_elements(tab_nu, RESIZE_OPTIONS::NOCOPY_NOINIT);
    }
  if (!tab_diffu.get_md_vector())
    {
      // diffusivite uniforme
      const int n = tab_nu.dimension_tot(0);
      const int nb_comp = tab_nu.line_size();
      CDoubleArrView diffu = static_cast<const DoubleVect&>(tab_diffu).view_ro();
      DoubleTabView nu = tab_nu.view_rw();
      Kokkos::parallel_for(start_gpu_timer(__KERNEL_NAME__),
                           range_2D({0, 0}, {n, nb_comp}),
                           KOKKOS_LAMBDA(const int i, const int j)
      {
        nu(i, j) = diffu(j);
      });
      end_gpu_timer(__KERNEL_NAME__);
    }
  else
    {
      assert(tab_nu.get_md_vector() == tab_diffu.get_md_vector());
      assert_espace_virtuel_vect(tab_diffu);
      // Sync arrays on the device before copy:
      mapToDevice(tab_diffu);
      computeOnTheDevice(tab_nu);
      tab_nu.inject_array(tab_diffu);
    }
}