Simpler.cpp

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#include <Simpler.h>
#include <Navier_Stokes_std.h>
#include <EChaine.h>
#include <Debog.h>
#include <Matrice_Bloc.h>
#include <Assembleur_base.h>
#include <Schema_Temps_base.h>
#include <TRUSTTrav.h>
 
#include <Probleme_base.h>
 
Implemente_instanciable(Simpler,"Simpler",Simple);
// XD simpler solveur_implicite_base simpler BRACE Simpler method for incompressible systems.
// XD attr seuil_convergence_implicite floattant seuil_convergence_implicite REQ Keyword to set the value of the
// XD_CONT convergence criteria for the resolution of the implicit system build to solve either the Navier_Stokes
// XD_CONT equation (only for Simple and Simpler algorithms) or a scalar equation. It is adviced to use the default
// XD_CONT value (1e6) to solve the implicit system only once by time step. This value must be decreased when a coupling
// XD_CONT between problems is considered.
// XD attr seuil_convergence_solveur floattant seuil_convergence_solveur OPT value of the convergence criteria for the
// XD_CONT resolution of the implicit system build by solving several times per time step the Navier_Stokes equation and
// XD_CONT the scalar equations if any. This value MUST be used when a coupling between problems is considered (should
// XD_CONT be set to a value typically of 0.1 or 0.01).
// XD attr seuil_generation_solveur floattant seuil_generation_solveur OPT Option to create a GMRES solver and use vrel
// XD_CONT as the convergence threshold (implicit linear system Ax=B will be solved if residual error ||Ax-B|| is lesser
// XD_CONT than vrel).
// XD attr seuil_verification_solveur floattant seuil_verification_solveur OPT Option to check if residual error
// XD_CONT ||Ax-B|| is lesser than vrel after the implicit linear system Ax=B has been solved.
// XD attr seuil_test_preliminaire_solveur floattant seuil_test_preliminaire_solveur OPT Option to decide if the
// XD_CONT implicit linear system Ax=B should be solved by checking if the residual error ||Ax-B|| is bigger than vrel.
// XD attr solveur solveur_sys_base solveur OPT Method (different from the default one, Gmres with diagonal
// XD_CONT preconditioning) to solve the linear system.
// XD attr no_qdm rien no_qdm OPT Keyword to not solve qdm equation (and turbulence models of these equation).
// XD attr nb_it_max entier nb_it_max OPT Keyword to set the maximum iterations number for the Gmres.
// XD attr controle_residu rien controle_residu OPT Keyword of Boolean type (by default 0). If set to 1, the convergence
// XD_CONT occurs if the residu suddenly increases.
 
 
Sortie& Simpler::printOn(Sortie& os ) const
{
  return Simple::printOn(os);
}
 
Entree& Simpler::readOn(Entree& is )
{
  return Simple::readOn(is);
}
 
// compute D correction_en_vitesse= E current + resu )
// with D = diagonal of the matrix and E = D-matrix =-(matrix-D)
int inverser_par_diagonale(const Matrice_Morse& matrice,const DoubleTrav& resu,const DoubleTab& current,DoubleTrav& correction_en_vitesse)
{
  const auto& tab1 = matrice.get_tab1();
  const auto& tab2 = matrice.get_tab2();
  const auto& coeff = matrice.get_coeff();
 
  int deux_entrees=0;
  int nb_comp=1;
  if (resu.nb_dim()==2)
    {
      deux_entrees=1;
      nb_comp=resu.dimension(1);
    }
  ConstDoubleTab_parts part(correction_en_vitesse);
  int nb_ligne_reel=part[0].dimension(0);
  // Determine U^
  if (deux_entrees==0)
    {
      for(int i=0; i<nb_ligne_reel; i++)
        {
          for(int j=0; j<nb_comp; j++)
            {
              double t=resu(i);
              for (auto k=tab1(i*nb_comp+j); k<tab1(i*nb_comp+j+1)-1; k++)
                t -= coeff(k)*current(tab2(k)-1);
 
              correction_en_vitesse(i) = t/matrice(i*nb_comp+j,i*nb_comp+j);
            }
        }
      // verif
      // test
      if (0)
        for(int i=0; i<nb_ligne_reel; i++)
          {
            for (int j=0; j<nb_comp; j++)
              {
                int ii=i*nb_comp+j;
                double tmp=resu(i);
                for (int k = 0; k<matrice.nb_colonnes(); k++)
                  if ((k/nb_comp)!=i)
                    {
                      if (matrice(ii,k))
                        tmp -= matrice(ii,k)*current((k/nb_comp));
                    }
 
                double test=tmp/matrice(ii,ii);
                if (!est_egal(test,correction_en_vitesse(i),1e-5))
                  {
                    Cerr<<i<<" "<<j<<" "<<resu(i)<<finl;
                    Cerr<<test<<" ici "<<correction_en_vitesse(i)-test<<finl;
                    return -1;
                  }
              }
          }
    }
 
  else
    {
      for(int i=0; i<nb_ligne_reel; i++)
        {
          for(int j=0; j<nb_comp; j++)
            {
              double t=resu(i,j);
              for (auto k=tab1(i*nb_comp+j); k<tab1(i*nb_comp+j+1)-1; k++)
                {
                  int i1 = (tab2(k)-1)/nb_comp;
                  int j1 = (tab2(k)-1)-i1*nb_comp;
                  t -= coeff(k)*current(i1,j1);
                }
              const double diagonal_coefficient = matrice(i*nb_comp+j,i*nb_comp+j);
              assert(diagonal_coefficient!=0);
              correction_en_vitesse(i,j) = t/diagonal_coefficient;
            }
        }
      // test
      if (0)
        {
          Cerr<<"milieu"<<finl;
          DoubleTrav corr2(correction_en_vitesse);
          matrice.multvect(current,corr2);
          for(int i=0; i<nb_ligne_reel; i++)
            {
              for (int j=0; j<nb_comp; j++)
                {
                  int ii = i*nb_comp+j;
                  corr2(i,j) = (resu(i,j)-corr2(i,j)+matrice(ii,ii)*current(i,j))/matrice(ii,ii);
                  double test = corr2(i,j);
                  if (!est_egal(test,correction_en_vitesse(i,j)))
                    {
                      Cerr<<i<<" "<<j<<" "<<resu(i,j)<<finl;
                      Cerr<<test<<" ici "<<correction_en_vitesse(i,j)<<" "<<current(i,j)<<" "<<matrice(ii,ii) <<finl;
                      return -1;
                    }
                }
            }
          Cerr<<"fin"<<finl;
        }
    }
  correction_en_vitesse.echange_espace_virtuel();
  return 0;
}
 
 
//Input: Uk-1 ; Pk-1
//Output: Uk ; Pk
//k denotes an iteration
 
void Simpler::iterer_NS(Equation_base& eqn,DoubleTab& current,DoubleTab& pression,double dt,Matrice_Morse& matrice,double seuil_resol,DoubleTrav& secmem,int nb_ite,int& converge, int& ok)
{
  if (eqn.probleme().is_dilatable())
    {
      Cerr<<" Simpler cannot be used with a quasi-compressible fluid."<<finl;
      Cerr<<__FILE__<<(int)__LINE__<<" non code" <<finl;
      exit();
    }
 
  Parametre_implicite& param = get_and_set_parametre_implicite(eqn);
  SolveurSys& le_solveur_ = param.solveur();
 
  Navier_Stokes_std& eqnNS = ref_cast(Navier_Stokes_std,eqn);
  eqnNS.reassembler_pression_si_necessaire();
  DoubleTrav gradP(current);
  DoubleTrav correction_en_pression(pression);
  DoubleTrav correction_en_vitesse(current);
  DoubleTrav resu(current);
 
  //int deux_entrees = 0;
  //if (current.nb_dim()==2) deux_entrees = 1;
  Operateur_Grad& gradient = eqnNS.operateur_gradient();
  Operateur_Div& divergence = eqnNS.operateur_divergence();
 
  //  int nb_comp = 1;
  //int nb_dim = current.nb_dim();
 
  //if (nb_dim==2)
  //  nb_comp = current.dimension(1);
 
  //Build matrix and residual
  //matrice = A[Uk-1] = M/dt + CONV +DIFF
  //resu =  A[Uk-1]Uk-1 -(A[Uk-1]Uk-1-Ss) + Sv -BtPk-1
  gradient.calculer(pression,gradP);
  if (eqnNS.has_interface_blocs()) /* if assembler_blocs is available */
    eqnNS.assembler_blocs_avec_inertie({{ "vitesse", &matrice }}, resu);
  else
    {
      resu -= gradP;
      eqnNS.assembler_avec_inertie(matrice,current,resu);
    }
 
  le_solveur_->reinit();
 
  //Solve the system: D[Uk-1]UPk = E[Uk-1]Uk-1 + Sv + Ss -BtPk-1 + (M/dt)Uk-1
  //matrice = A[Uk-1] = D - E with D the diagonal part of A
  //correction_en_vitesse = UPk ; current = Uk-1 ; resu = Sv + Ss -BtPk-1
  int status = inverser_par_diagonale(matrice,resu,current,correction_en_vitesse);
  if (status!=0) exit();
  Debog::verifier("Simpler::iterer_NS correction_en_vitesse",correction_en_vitesse);
 
  //Build matrice_en_pression_2 = BD-1Bt[Uk-1]
  Matrice& matrice_en_pression_2 = eqnNS.matrice_pression();
  assembler_matrice_pression_implicite(eqnNS,matrice,matrice_en_pression_2);
  SolveurSys& solveur_pression_ = eqnNS.solveur_pression();
  solveur_pression_->reinit();
 
  //Compute BUPk
  divergence.calculer(correction_en_vitesse,secmem);
  secmem *= -1;
  secmem.echange_espace_virtuel();
  if (nb_ite==1)
    eqnNS.assembleur_pression()->modifier_secmem(secmem);
 
  //Solve the system (BD-1Bt)P*_k = BUPk
  //correction_en_pression = P*_k ; secmem = BUPk
  solveur_pression_.resoudre_systeme(matrice_en_pression_2.valeur(),
                                     secmem,correction_en_pression);
 
  //Compute Pk = Pk-1 + P*_k
  operator_add(pression, correction_en_pression, VECT_ALL_ITEMS);
 
  eqnNS.assembleur_pression()->modifier_solution(pression);
 
  //Compute Bt P*_k and adjust resu to -Bt Pk
  gradient->multvect(correction_en_pression,gradP);
  resu -= gradP;
  resu.echange_espace_virtuel();
  Debog::verifier("Simpler::iterer_NS resu",resu);
 
  //Solve the system: A[Uk-1]U*_k = -BtPk + Sv + Ss + (M/dt)Uk-1
  //current = U*_k ; resu = A[Uk-1]Uk-1 - (A[Uk-1]Uk-1-Ss) + Sv -BtPk + (M/dt)Uk-1
  le_solveur_.resoudre_systeme(matrice,resu,current);
 
  //Compute BU*_k
  divergence.calculer(current,secmem);
  secmem *= -1;
  secmem.echange_espace_virtuel();
  Debog::verifier("Simpler::iterer_NS secmem",secmem);
 
  //Solve the system (BD-1Bt)P'k = BU*_k
  //correction_en_pression = P'k ; secmem = BU*_k
  correction_en_pression = 0;
  solveur_pression_.resoudre_systeme(matrice_en_pression_2.valeur(),
                                     secmem,correction_en_pression);
 
  //Solve the system D[Uk-1](Uk-U*_k) = -BtP'k
  //correction_en_vitesse = U'k = Uk-U*_k ; correction_en_pression = P'k
  calculer_correction_en_vitesse(correction_en_pression,gradP,correction_en_vitesse,matrice,gradient);
 
  if (0)
    {
      Cerr<<" rr "<<mp_max_abs_vect(secmem)<<finl;
      //Cerr<<secmem<<finl;
      secmem*=-1;
      divergence.ajouter(correction_en_vitesse, secmem);
      Cerr<<" rr2 "<<mp_max_abs_vect(secmem)<<finl;
 
    }
 
  //Compute Uk = U*_k + U'k
  current += correction_en_vitesse;
  current.echange_espace_virtuel();
  Debog::verifier("Simpler::iterer_NS current",current);
 
  if (0)
    {
      divergence.calculer(current, secmem);
      Cerr<<" apresdiv "<<mp_max_abs_vect(secmem)<<finl;;
    }
 
}