Implicit_steady.h

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#ifndef Implicit_steady_included
#define Implicit_steady_included
 
#include <Simpler.h>
#include <Navier_Stokes_std.h>
#include <Nom.h>
 
// Like the Implicite algorithm (Piso with avancement_crank_=0), IMPLICITE_STEADY
// splits into a prediction step and a correction step.
// The scalar time step dt is replaced by a vector of local time steps (one per face).
// The pressure matrix (B*(M/dt_loc)^-1*Bt) is reassembled when dt_loc changes significantly.
 
class Implicit_steady : public Simpler
{
 
  Declare_instanciable_sans_constructeur(Implicit_steady);
 
public :
 
  Implicit_steady();
  //Modification of the projection and correction steps for the taking into account of a local time step
  void iterer_NS(Equation_base&, DoubleTab& current, DoubleTab& pression, double, Matrice_Morse&, double, DoubleTrav&,int nb_iter,int& converge, int& ok) override;
  // Compute M/dt_loc = rho * V_entrelace * porosite / dt_loc per face
  void calcul_mat_masse_diviser_par_dt(Navier_Stokes_std& eqnNS, DoubleVect& m_dt, const DoubleVect& dt_loc);
 
  inline const Nom& le_nom() const override
  {
    static Nom nom="Implicit_steady";
    return nom;
  };
 
 
 
protected:
  double seuil_variation_dt_ = 0.25; // 25% variation triggers reassembly (max safe with security_factor=0.8)
  int    reassembly_interval_ = 100; // reassemble at most every N time steps
};
 
 
 
 
 
 
#endif