Modele_turbulence_scal_Prandtl.cpp

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#include <Pb_Thermohydraulique_Turbulent_QC.h>
#include <Modele_turbulence_scal_Prandtl.h>
#include <Modifier_pour_fluide_dilatable.h>
#include <Champ_Uniforme.h>
#include <Domaine_VF.h>
#include <Parser_U.h>
#include <ParserView.h>
#include <Motcle.h>
#include <Param.h>
 
Implemente_instanciable(Modele_turbulence_scal_Prandtl, "Modele_turbulence_scal_Prandtl", Modele_turbulence_scal_diffturb_base);
// XD prandtl modele_turbulence_scal_base prandtl INHERITS_BRACE The Prandtl model. For the scalar equations, only the
// XD_CONT model based on Reynolds analogy is available. If K_Epsilon was selected in the hydraulic equation, Prandtl
// XD_CONT must be selected for the convection-diffusion temperature equation coupled to the hydraulic equation and
// XD_CONT Schmidt for the concentration equations.
 
Sortie& Modele_turbulence_scal_Prandtl::printOn(Sortie& s) const { return Modele_turbulence_scal_diffturb_base::printOn(s); }
 
Entree& Modele_turbulence_scal_Prandtl::readOn(Entree& is)
{
  Modele_turbulence_scal_diffturb_base::readOn(is);
  // if a function was read, initialize the Parser
  if (definition_fonction_ != Nom())
    {
      fonction_.setNbVar(2);
      fonction_.addVar("alpha");
      fonction_.addVar("nu_t");
      fonction_.setString(definition_fonction_);
      fonction_.parseString();
    }
 
  if (LePrdt_fct_ != Nom())
    {
      fonction1_.setNbVar(3);
      fonction1_.addVar("x");
      fonction1_.addVar("y");
      fonction1_.addVar("z");
      fonction1_.setString(LePrdt_fct_);
      fonction1_.parseString();
    }
  else
    Cerr << "The default value of the turbulent Prandtl number is " << LePrdt_ << finl;
 
  Cerr << "The expression for the turbulent Prandtl number is " << LePrdt_fct_ << finl;
  return is;
}
 
void Modele_turbulence_scal_Prandtl::set_param(Param& param) const
{
  param.ajouter("Prdt", &LePrdt_fct_); // XD_ADD_P chaine
  // XD_CONT Keyword to modify the constant (Prdt) of Prandtl model : Alphat=Nut/Prdt Default value is 0.9
  param.ajouter("Prandt_turbulent_fonction_nu_t_alpha", &definition_fonction_); // XD_ADD_P chaine
  // XD_CONT Optional keyword to specify turbulent diffusivity (by default, alpha_t=nu_t/Prt) with another formulae, for
  // XD_CONT example: alpha_t=nu_t2/(0,7*alpha+0,85*nu_tt) with the string nu_t*nu_t/(0,7*alpha+0,85*nu_t) where alpha
  // XD_CONT is the thermal diffusivity.
  Modele_turbulence_scal_base::set_param(param);
}
 
/*! @brief Computes the turbulent diffusivity and applies the wall law.
 *
 * @param Unused time parameter.
 */
void Modele_turbulence_scal_Prandtl::mettre_a_jour(double)
{
  calculer_diffusivite_turbulente();
  const Milieu_base& mil = equation().probleme().milieu();
  if (loi_paroi_non_nulle())
    loipar_->calculer_scal(diffusivite_turbulente_);
 
  const Probleme_base& mon_pb = mon_equation_->probleme();
  DoubleTab& lambda_t = conductivite_turbulente_->valeurs();
  lambda_t = diffusivite_turbulente_->valeurs();
  const bool uniforme = sub_type(Champ_Uniforme, mon_pb.milieu().capacite_calorifique());
  const DoubleTab& tab_Cp = mon_pb.milieu().capacite_calorifique().valeurs();
  const DoubleTab& tab_rho = mon_pb.milieu().masse_volumique().valeurs();
  if (sub_type(Pb_Thermohydraulique_Turbulent_QC, mon_pb))
    {
      CDoubleArrView Cp = static_cast<const DoubleVect&>(tab_Cp).view_ro();
      DoubleArrView lambda = static_cast<DoubleVect&>(lambda_t).view_rw();
      Kokkos::parallel_for(start_gpu_timer(__KERNEL_NAME__), lambda_t.size(),
                           KOKKOS_LAMBDA(
                             const int i)
      {
        lambda(i) *= Cp(uniforme ? 0 : i);
      });
      end_gpu_timer(__KERNEL_NAME__);
      if (equation().probleme().is_dilatable())
        multiplier_par_rho_si_dilatable(lambda_t, mil);
    }
  else
    lambda_t *= mon_equation_->domaine_dis().nb_elem() > 0 ? tab_rho(0, 0) * tab_Cp(0, 0) : 1.0;
  lambda_t.echange_espace_virtuel();
  diffusivite_turbulente_->valeurs().echange_espace_virtuel();
}
 
/*! @brief Computes the turbulent diffusivity.
 *
 * turbulent_diffusivity = turbulent_viscosity / turbulent_Prandtl_number
 *
 * @return The newly computed turbulent diffusivity field.
 * @throws If diffusivite_turbulente and viscosite_turbulente fields do not have the same number of nodal values.
 */
Champ_Fonc_base& Modele_turbulence_scal_Prandtl::calculer_diffusivite_turbulente()
{
  DoubleTab& tab_alpha_t = diffusivite_turbulente_->valeurs();
  const DoubleTab& tab_nu_t = la_viscosite_turbulente_->valeurs();
  double temps = la_viscosite_turbulente_->temps();
 
 
  int n = tab_alpha_t.size();
  if (tab_nu_t.size() != n)
    {
      Cerr << "The DoubleTab arrays of diffusivite_turbulente and viscosite_turbulente fields" << finl;
      Cerr << "must have the same number of nodal values" << finl;
      exit();
    }
 
  if (definition_fonction_ != Nom())
    {
      // modif VB to use the equation approaching Yakhot: LePrdt = 0.7/Pe-t + 0.85
      // Pe-t is a turbulent Peclet number defined by Pr*(nut/nu)
      // giving alpha_t = nut * nut / ( 0.7 alpha + 0.85 nut )
 
      const Milieu_base& milieu = mon_equation_->milieu();
      const Champ_Don_base& alpha = milieu.diffusivite();
      if (!milieu.has_diffusivite())
        {
          // GF if this condition is blocking, we could improve by
          // attempting to create a parser without the variable alpha; if successful, alpha exists, is constant, and equals 1.
          Cerr << "Error in Modele_turbulence_scal_prandtl, the Prandt_turbulent_fonction_nu_t_alpha option is only available for media with a defined diffusivity" << finl;
          exit();
        }
      double d_alpha = 0.;
      const bool is_alpha_unif = sub_type(Champ_Uniforme, alpha);
      if (is_alpha_unif)
        d_alpha = alpha.valeurs()(0, 0);
 
      ParserView parser(fonction_);
      parser.parseString();
      CDoubleArrView alpha_vals;
      if (!is_alpha_unif) alpha_vals = static_cast<const ArrOfDouble&>(alpha.valeurs()).view_ro();
      CDoubleArrView nu_t = static_cast<const DoubleVect&>(tab_nu_t).view_ro();
      DoubleArrView alpha_t = static_cast<DoubleVect&>(tab_alpha_t).view_rw();
      Kokkos::parallel_for(start_gpu_timer(__KERNEL_NAME__), Kokkos::RangePolicy<>(0, n), KOKKOS_LAMBDA(const int i)
      {
        double alpha_val = is_alpha_unif ? d_alpha : alpha_vals(i);
        int threadId = parser.acquire();
        parser.setVar(0, alpha_val, threadId);
        parser.setVar(1, nu_t[i], threadId);
        alpha_t[i] = parser.eval(threadId);
        parser.release(threadId);
      });
      end_gpu_timer(__KERNEL_NAME__);
    }
  else
    {
      if (LePrdt_fct_ != Nom())
        {
          const int nb_dim = dimension;
          ParserView parser(fonction1_);
          parser.parseString();
          CDoubleTabView xp = ref_cast(Domaine_VF,mon_equation_->domaine_dis()).xp().view_ro();
          CDoubleArrView nu_t = static_cast<const DoubleVect&>(tab_nu_t).view_ro();
          DoubleArrView alpha_t = static_cast<DoubleVect&>(tab_alpha_t).view_rw();
          Kokkos::parallel_for(start_gpu_timer(__KERNEL_NAME__), Kokkos::RangePolicy<>(0, n), KOKKOS_LAMBDA(const int i)
          {
            double x = xp(i, 0);
            double y = xp(i, 1);
            double z = nb_dim == 3 ? xp(i, 2) : 0.;
            int threadId = parser.acquire();
            parser.setVar(0, x, threadId);
            parser.setVar(1, y, threadId);
            parser.setVar(2, z, threadId);
            double NbPrandtlCell = parser.eval(threadId);
            parser.release(threadId);
            alpha_t[i] = nu_t[i] / NbPrandtlCell;
          });
          end_gpu_timer(__KERNEL_NAME__);
        }
      else
        {
          double inv_LePrdt = 1./LePrdt_;
          // ToDo Kokkos: implement operator_mutiply(u,v,alpha);
          // if u = v * alpha is a regular pattern in the code...
          CDoubleArrView nu_t = static_cast<const DoubleVect&>(tab_nu_t).view_ro();
          DoubleArrView alpha_t = static_cast<DoubleVect&>(tab_alpha_t).view_rw();
          Kokkos::parallel_for(start_gpu_timer(__KERNEL_NAME__),
                               Kokkos::RangePolicy<>(0, n), KOKKOS_LAMBDA(
                                 const int i)
          {
            alpha_t[i] = nu_t[i] * inv_LePrdt;
          });
          end_gpu_timer(__KERNEL_NAME__);
        }
    }
 
  diffusivite_turbulente_->changer_temps(temps);
 
  if (equation().probleme().is_dilatable())
    diviser_par_rho_si_dilatable(diffusivite_turbulente_->valeurs(), equation().probleme().milieu());
  return diffusivite_turbulente_.valeur();
}