Op_Evanescence_Homogene_Face_base.cpp

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#include <Op_Evanescence_Homogene_Face_base.h>
#include <Viscosite_turbulente_base.h>
#include <Vitesse_relative_base.h>
#include <Gravite_Multiphase.h>
#include <Milieu_composite.h>
#include <Champ_Face_base.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_Face_base,"Op_Evanescence_Homogene_Face_base",Operateur_Evanescence_base);
 
Sortie& Op_Evanescence_Homogene_Face_base::printOn(Sortie& os) const { return os; }
 
Entree& Op_Evanescence_Homogene_Face_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);
 
  Pb_Multiphase& pbm = ref_cast(Pb_Multiphase, equation().probleme());
  if (pbm.has_correlation("Vitesse_relative") && !pbm.has_correlation("gravite")) Process::exit(que_suis_je() + " : you must define a multiphase gravity field if you want a drift flux!!");
  if (pbm.has_correlation("Vitesse_relative") && ref_cast(Vitesse_relative_base, pbm.get_correlation("Vitesse_relative")).needs_vort()) pbm.creer_champ("vorticite");
 
  return is;
}
 
void Op_Evanescence_Homogene_Face_base::dimensionner_blocs(matrices_t matrices, const tabs_t& semi_impl) const
{
  const Champ_Face_base& ch = ref_cast(Champ_Face_base, equation().inconnue());
  const Domaine_VF& domaine = ref_cast(Domaine_VF, equation().domaine_dis());
  const DoubleTab& inco = ch.valeurs();
  const IntTab& fcl = ch.fcl();
 
  /* we must be able to add / subtract equations between components */
  int i, f, 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())
      {
        Stencil sten(0, 2);
 
 
        std::set<int> idx;
        Matrice_Morse& mat = *n_m.second, mat2;
        /* face equations: only those computed */
        for (f = 0; f < domaine.nb_faces(); f++, idx.clear())
          if (fcl(f, 0) < 2)
            {
              for (i = N * f, 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 * f, n = 0; n < N; n++, i++)
                for (auto &&c : idx)
                  if (c >= 0)
                    sten.append_line(i, c);
            }
          else if (n_m.first == ch.le_nom().getString()) /* CLs a valeur imposee : diagonale */
            for (n = 0, i = N * f; n < N; n++, i++) sten.append_line(i, i);
 
        /* equations aux elements si aux */
        dimensionner_blocs_aux(idx, sten, mat);
 
        Matrix_tools::allocate_morse_matrix(mat.nb_lignes(), mat.nb_colonnes(), sten, mat2);
        mat = mat2; //to force the ordering of coefficients in the matrix (speeds up row-by-row operations)
      }
}
 
void Op_Evanescence_Homogene_Face_base::ajouter_blocs(matrices_t matrices, DoubleTab& secmem, const tabs_t& semi_impl) const
{
 
  const Pb_Multiphase& pbm = ref_cast(Pb_Multiphase, equation().probleme());
  const bool reso_en_T = pbm.resolution_en_T();
  const Milieu_composite& milc = ref_cast(Milieu_composite, equation().milieu());
  const Champ_Face_base& ch = ref_cast(Champ_Face_base, equation().inconnue());
  const Domaine_VF& domaine = ref_cast(Domaine_VF, equation().domaine_dis());
  const IntTab& f_e = domaine.face_voisins(), &fcl = ch.fcl();
  const DoubleTab& inco = ch.valeurs(), &vfd = domaine.volumes_entrelaces_dir(),
                   &alpha = ref_cast(Pb_Multiphase, equation().probleme()).equation_masse().inconnue().passe(),
                    &rho = equation().milieu().masse_volumique().passe(),
                     &temp_ou_enth  = ref_cast(Pb_Multiphase, equation().probleme()).equation_energie().inconnue().passe(),
                      &press = ref_cast(QDM_Multiphase, ref_cast(Pb_Multiphase, equation().probleme()).equation_qdm()).pression().passe(),
                       &mu = ref_cast(Milieu_composite, equation().milieu()).viscosite_dynamique().passe(),
                        *d_bulles = (equation().probleme().has_champ("diametre_bulles")) ? &equation().probleme().get_champ("diametre_bulles").valeurs() : nullptr,
                         *k_turb = (equation().probleme().has_champ("k")) ? &equation().probleme().get_champ("k").passe() : nullptr,
                          *gravity = (equation().probleme().has_champ("gravite")) ? &equation().probleme().get_champ("gravite").valeurs() : nullptr ;
 
  const DoubleVect& vf = domaine.volumes_entrelaces(), &dh_e = milc.diametre_hydraulique_elem();
  int e, f, k, l, n, m, N = inco.line_size(), Nk = (k_turb) ? (*k_turb).line_size() : 0, d, D = dimension, cR = (rho.dimension_tot(0) == 1), cM = (mu.dimension_tot(0) == 1), Np = press.line_size(),
                        iter = sub_type(SETS, equation().schema_temps()) ? 0 * ref_cast(SETS, equation().schema_temps()).iteration_ : 0;
 
  if (N == 1) return; //no evanescence in single-phase flow!
 
  double a_eps = alpha_res_, a_eps_min = alpha_res_min_, a_m, a_max; //threshold for triggering evanescence treatment
 
  /* search for evanescent phases and treatment of right-hand sides */
  IntTrav maj(inco.dimension_tot(0)); //maj(i): dominant phase for row i
  DoubleTrav coeff(inco.dimension_tot(0), inco.line_size(), 2); //coeff(i, n, 0/1): coefficient to apply to the existing equation / to the eq. "inco = v_maj"
  Matrice_Morse& mat_diag = *matrices.at(ch.le_nom().getString());
 
  DoubleTab dvr_face(domaine.nb_faces(), N, N, N); // Derivative of vr(n,k) at f with respect to phase l; for now always along d2=d
  // Carried along because someone separated the matrix loop from the right-hand-side loop
 
  /* compute the drift velocity: retrieve the required intermediate quantities */
  Vitesse_relative_base::input_t in;
  Vitesse_relative_base::output_t out;
  out.vr.resize(N, N, D), out.dvr.resize(N, N, D, N*D);
  const Vitesse_relative_base* correlation_vd = pbm.has_correlation("vitesse_relative") ? &ref_cast(Vitesse_relative_base, pbm.get_correlation("vitesse_relative")) : nullptr;
  DoubleTab gradAlpha, vort, nut;
  const int is_turb = ref_cast(Operateur_Diff_base, ref_cast(QDM_Multiphase, pbm.equation_qdm()).operateur_diff().l_op_base()).is_turb();
  if (correlation_vd)
    {
      in.alpha.resize(N), in.rho.resize(N), in.mu.resize(N), in.d_bulles.resize(N), in.k.resize(N), in.nut.resize(N), in.v.resize(D, N), in.sigma.resize(N*(N-1)/2), in.g.resize(D);
      if (correlation_vd->needs_grad_alpha())
        {
          gradAlpha.resize(domaine.nb_faces(), D, N);
          calc_grad_alpha_faces(gradAlpha);
          in.gradAlpha.resize(D, N);
        }
      if (correlation_vd->needs_vort())
        {
          vort.resize(domaine.nb_faces(), D, N);
          calc_vort_faces(vort);
          in.vort.resize(D, N);
        }
      if (is_turb)
        {
          nut.resize(domaine.nb_elem_tot(), N);
          ref_cast(Viscosite_turbulente_base, (*ref_cast(Operateur_Diff_base, equation().operateur(0).l_op_base()).correlation_viscosite_turbulente())).eddy_viscosity(nut); //filled by the correlation
        }
    }
 
  for (f = 0; f < domaine.nb_faces(); f++)
    if (fcl(f, 0) < 2)
      {
        /* dominant phase: with interpolated alpha by default, with upwind alpha for SETS / ICE iterations */
        for (a_max = 0, k = -1, n = 0; n < N; n++)
          {
            if (iter) a_m = alpha(f_e(f, f_e(f, 1) >= 0 && inco(f, n) < 0), n);
            else
              {
                int i;
                for (a_m = 0, i = 0; i < 2; i++)
                  if ((e = f_e(f, i)) >= 0)
                    a_m += vfd(f, i) / vf(f) * alpha(e, n);
              }
            if (a_m > a_max) k = n, a_max = a_m;
          }
        if (k >= 0) maj(f) = k;
        else abort();
 
        if (correlation_vd)
          {
            for (n = 0; n < N; n++)
              for (d = 0; d < D; d++) in.v(d, n) = inco(f, n) * domaine.face_normales(f, d) / domaine.face_surfaces(f);
            int i;
            for (in.alpha = 0, in.rho = 0, in.mu = 0, in.d_bulles = 0, in.k = 0, in.nut = 0, in.dh = 0, in.g = 0, i = 0; i < 2 && (e = f_e(f, i)) >= 0; i++)
              {
                in.dh += vfd(f, i) / vf(f) * dh_e(e); // should not be in the loop on N below.
                for (n = 0; n < N; n++)
                  {
                    in.alpha(n) += vfd(f, i) / vf(f) * alpha(e, n);
                    in.rho(n) += vfd(f, i) / vf(f) * rho(!cR * e, n);
                    in.mu(n) += vfd(f, i) / vf(f) * mu(!cM * e, n);
                    in.d_bulles(n)+=vfd(f, i) / vf(f) *((d_bulles) ? (*d_bulles)(e, n) : -1.) ;
                    for (m = n+1; m < N; m++)
                      if (milc.has_interface(n, m))
                        {
                          const int ind_trav = (n*(N-1)-(n-1)*(n)/2) + (m-n-1); // upper triangular matrix indexing!
                          Interface_base& sat = milc.get_interface(n, m);
                          in.sigma(ind_trav) = reso_en_T ? sat.sigma(temp_ou_enth(e, n), press(e, n * (Np > 1))) : sat.sigma_h(temp_ou_enth(e, n), press(e, n * (Np > 1)));
                        }
                  }
                for (n = 0; n < Nk; n++) in.k(n) += vfd(f, i) / vf(f) *((k_turb) ? (*k_turb)(e, n) : -1.), in.nut(n) += vfd(f, i) / vf(f) *((is_turb) ? nut(e, n) : -1.) ;
                for (d = 0; d < D; d++) in.g(d) += vfd(f, i) / vf(f) * (*gravity)(e,d);
                if (correlation_vd->needs_grad_alpha())
                  for (n = 0; n < N; n++)
                    for (d = 0; d < D; d++) in.gradAlpha(d, n) = gradAlpha(f, d, n);
                if (correlation_vd->needs_vort())
                  for (n = 0; n < N; n++)
                    for (d = 0; d < D; d++) in.vort(d, n) = vort(f, d, n);
              }
            correlation_vd->vitesse_relative(in, out);
          }
 
        /* evanescent phases: with upwind alpha. The dominant phase cannot be evanescent! */
        for (n = 0; n < N; n++)
          {
            if (iter) a_m = alpha(f_e(f, f_e(f, 1) >= 0 && inco(f, n) < 0), n);
            else
              {
                int i;
                for (a_m = 0, i = 0; i < 2; i++)
                  if ((e = f_e(f, i)) >= 0)
                    a_m += vfd(f, i) / vf(f) * alpha(e, n);
              }
            if (n != k && a_m < a_eps)
              {
                coeff(f, n, 1) = mat_diag(N * f + k, N * f + k) * (coeff(f, n, 0) = std::min(std::max((a_eps - a_m) / (a_eps - a_eps_min), 0.), 1.));
                DoubleTab vr_face(N, N);
                for (d = 0; d < D; ++d)
                  {
                    vr_face(n, k) += out.vr(n, k, d) * domaine.face_normales(f, d) / domaine.face_surfaces(f);
                    for (l=0 ; l<N ; l++) dvr_face(f, n, k,l) += out.dvr(n, k, d, l*D+d) * domaine.face_normales(f, d) / domaine.face_surfaces(f);
                  }
                double flux = coeff(f, n, 0) * secmem(f, n) + coeff(f, n, 1) * (inco(f, n) - inco(f, k) - vr_face(n, k));
                secmem(f, k) += flux, secmem(f, n) -= flux;
              }
          }
      }
 
  /* lignes de matrices */
  for (auto &&n_m : matrices)
    if (n_m.second->nb_colonnes())
      {
        int diag = (n_m.first == ch.le_nom().getString()); //are we on the diagonal block?
        Matrice_Morse& mat = *n_m.second;
        /* faces */
        for (f = 0; f < domaine.nb_faces(); f++)
          if (fcl(f, 0) < 2)
            for (n = 0; n < N; n++)
              if (coeff(f, n, 0))
                {
                  k = maj(f);
                  for (auto i = mat.get_tab1()(N * f + n) - 1, j = mat.get_tab1()(N * f + k) - 1; i < mat.get_tab1()(N * f + n + 1) - 1; i++, j++)
                    {
                      assert(mat.get_tab2()(i) == mat.get_tab2()(j));
                      int c = diag * mat.get_tab2()(i) - 1; //column index (shared by both rows thanks to dimensionner_blocs())
                      mat.get_set_coeff()(j) +=  coeff(f, n, 0) * mat.get_set_coeff()(i) - coeff(f, n, 1) * ((c == N * f + n) - (c == N * f + k));
                      mat.get_set_coeff()(i) += -coeff(f, n, 0) * mat.get_set_coeff()(i) + coeff(f, n, 1) * ((c == N * f + n) - (c == N * f + k));
 
                      mat.get_set_coeff()(j) +=  - coeff(f, n, 1) * ( - dvr_face(f, n, k, n)*(c == N * f + n) - dvr_face(f, n, k, n)*(c == N * f + k));
                      mat.get_set_coeff()(i) +=  + coeff(f, n, 1) * ( - dvr_face(f, n, k, n)*(c == N * f + n) - dvr_face(f, n, k, k)*(c == N * f + k));
                    }
                }
      }
 
  // if auxiliary variables:
  ajouter_blocs_aux(maj, coeff, matrices, secmem);
}
 
void Op_Evanescence_Homogene_Face_base::calc_vort_faces(DoubleTab& vort) const
{
  vort = 0;
  const Domaine_VF& domaine = ref_cast(Domaine_VF, equation().domaine_dis());
  const IntTab& f_e = domaine.face_voisins();
  const DoubleVect& vf = domaine.volumes_entrelaces(), &fs = domaine.face_surfaces();
  const DoubleTab& n_f = domaine.face_normales(), &vfd = domaine.volumes_entrelaces_dir();
  const DoubleTab& vorticite = equation().probleme().get_champ("vorticite").passe(),
                   &grad_v = equation().probleme().get_champ("gradient_vitesse").passe();
 
  const int D = dimension, N = vort.dimension_tot(2), nf = domaine.nb_faces(), nf_tot = domaine.nb_faces_tot();
  int c, e, f, n, d, d2, n_l = 0;
  DoubleTrav grad_l(D, D), scal_grad(D);
 
  for (f = 0; f < nf; f++)
    for (c = 0; c < 2; c++)
      {
        e = f_e(f, c);
 
        if (e < 0)
          continue;
 
        if (D == 2)
          {
            for (n = 0; n < N; n++)
              for (d = 0; d < D; d++)
                vort(f, d, n) += vorticite(e, n) * vfd(f, c) / vf(f);
          }
        else
          {
            for (n = 0; n < N; n++)
              for (d = 0; d < D; d++)
                vort(f, d, n) += vorticite(e, N * d + n) * vfd(f, c) / vf(f);
          }
      }
 
  if (D == 3)
    for (f = 0; f < nf; f++)
      {
        grad_l = 0; // we fill grad_l so that grad_l(d, d2) = du_d/dx_d2 by averaging between both elements
        for (d = 0; d < D; d++)
          for (d2 = 0; d2 < D; d2++)
            for (c = 0; c < 2 && (e = f_e(f, c)) >= 0; c++)
              grad_l(d, d2) += vfd(f, c) / vf(f) * grad_v(nf_tot + D * e + d2, n_l * D + d);
        //We replace the n_l components by the one calculated without interpolation to elements
        scal_grad = 0; // scal_grad(d) = grad(u_d).n_f
        for (d = 0; d < D; d++)
          for (d2 = 0; d2 < D; d2++)
            scal_grad(d) += grad_l(d, d2) * n_f(f, d2) / fs(f);
        for (d = 0; d < D; d++)
          for (d2 = 0; d2 < D; d2++)
            grad_l(d, d2) += (grad_v(f, n_l * D + d) - scal_grad(d)) * n_f(f, d2) / fs(f);
        // We calculate the local vorticity using this local gradient
        vort(f, 0, n_l) = grad_l(2, 1) - grad_l(1, 2); // dUz/dy - dUy/dz
        vort(f, 1, n_l) = grad_l(0, 2) - grad_l(2, 0); // dUx/dz - dUz/dx
        vort(f, 2, n_l) = grad_l(1, 0) - grad_l(0, 1); // dUy/dx - dUx/dy
      }
}