Simpler_Base.h

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#ifndef Simpler_Base_included
#define Simpler_Base_included
 
#include <Solveur_non_lineaire.h>
#include <Parametre_implicite.h>
#include <TRUSTTabs_forward.h>
#include <Nom.h>
 
class Solveur_Implicite_base;
class Schema_Temps_base;
class Equation_base;
class Matrice_Morse;
class Matrice;
class Sources;
class Motcle;
 
//Description
//
// Base class for implicit equation solvers.
// The equation is discretised as:
// (M/dt + C(U) + D)Xn+1 = Sv + Ss + (M/dt)Xn
// where
// C(U) convection matrix
// D    diffusion matrix
// M    mass matrix
// Sv   volumetric source term
// Ss   surface source term (Neumann condition)
// Xn and Xn+1 denote the unknown at times tn and tn+1 respectively
//
// At each time step (tn) we solve the following system:
//         A[Xk] = b[Xk]
// with
// A[Xk] = (M/dt + C(Uk) + D)
// b[Xk] = Sv + Ss + (M/dt)Xk
// k denotes an iteration index for the iterative resolution of the matrix system (tn fixed)
 
// The resolution method used to determine X is a fixed-point method:
// Set f(Xk) = A[Xk]Xk - b[Xk] so that the solution Xsol satisfies f(Xsol) = 0
// A first-order Taylor expansion gives:
// Xk - Xk+1 = f(Xk)/f'(Xk)
// Making the hypothesis f' = A (not strictly true for the convection part)
// the system becomes: A[Xk](Xk-Xk+1) = f(Xk) or equivalently
//                     A[Xk]Xk+1 = A[Xk]Xk - (A[Xk]Xk-Ss) + Sv +(M/dt)Xk
//
//
// Method iterer_eqn() for equations other than Navier-Stokes:
// - builds the matrix (matrice) and right-hand side (resu) from the equation (assembler_avec_inertie(...))
// - triggers the matrix system resolution (le_solveur_.resoudre_systeme(...))
 
// Method iterer_NS() called by iterer_eqn() for the specific case of the Navier-Stokes equation.
// Available algorithms: Simple - Simpler - Piso - Implicite
// See subclasses of Simpler_base for descriptions of the respective algorithms.
 
 
class Simpler_Base : public  Solveur_non_lineaire
{
  Declare_base_sans_constructeur(Simpler_Base);
 
public :
 
  inline int max_iter_implicite();
  inline int max_iter_implicite() const;
 
  bool iterer_eqn(Equation_base& equation, const DoubleTab& inconnue, DoubleTab& result, double dt, int numero_iteration, int& ok) override =0;
 
  virtual void iterer_NS(Equation_base&, DoubleTab& current, DoubleTab& pression, double, Matrice_Morse&, double, DoubleTrav&,int nb_iter,int& converge, int& ok)=0;
 
  void assembler_matrice_pression_implicite(Equation_base& eqn_NS,const Matrice_Morse& matrice,Matrice& matrice_en_pression_2);
 
protected :
 
  int no_qdm_;
  double facsec_diffusion_for_sets_ = -1.;
 
  Entree& lire(const Motcle&, Entree&) override;
  int get_controle_residu() const override { return controle_residu_; }
};
 
#endif