Convection_tools.h

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#ifndef Convection_tools_included
#define Convection_tools_included
#include <kokkos++.h>
 
//////////////////////////////////////////////////////////////
//   Fonctions limiteurs de MUSCL
////////////////////////////////////////////////////////////////
 
KOKKOS_INLINE_FUNCTION
double minmod(double grad1, double grad2)
{
  double gradlim=0.;
  if(grad1*grad2>0.) (std::fabs(grad1)<std::fabs(grad2)) ? gradlim=grad1 : gradlim=grad2 ;
  return gradlim;
}
 
KOKKOS_INLINE_FUNCTION double vanleer(double grad1, double grad2)
{
  double gradlim=0.;
  if(grad1*grad2>0.) gradlim=2.*grad1*grad2/(grad1+grad2) ;
  return gradlim;
}
 
KOKKOS_INLINE_FUNCTION double vanalbada(double grad1, double grad2)
{
  double gradlim=0.;
  if(grad1*grad2>0.) gradlim=grad1*grad2*(grad1+grad2)/(grad1*grad1+grad2*grad2) ;
  return gradlim;
}
 
KOKKOS_INLINE_FUNCTION double chakravarthy(double grad1, double grad2)
{
  /*
    Cerr << " limiteur chakavarthy non preconise (non symetrique) " << finl;
    exit();
    return 0;
  */
  double gradlim=0.;
  if ((grad1*grad2)>0)
    {
      gradlim=Kokkos::min(grad1/grad2,1.8); // 1<<beta<<2
      gradlim=Kokkos::max(gradlim,0.);
      gradlim*=grad2;
    }
  return gradlim;
}
 
KOKKOS_INLINE_FUNCTION double superbee(double grad1, double grad2)
{
  /*
    Cerr << " limiteur superbee non preconise (source d'instabilites) " << finl;
    exit();
    return 0;
  */
  double gradlim=0.;
  if ((grad1*grad2)>0)
    {
      double gradlim1,gradlim2;
      gradlim1=Kokkos::min(2*(grad1/grad2),1.);
      gradlim2=Kokkos::min(grad1/grad2,2.);
      gradlim=Kokkos::max(gradlim1,gradlim2);
      gradlim=Kokkos::max(gradlim,0.);
      gradlim*=grad2;
    }
  return gradlim;
}
 
KOKKOS_INLINE_FUNCTION
double FCT_LIMITEUR(double grad1, double grad2, int cas)
{
  switch(cas)
    {
    case 1:
      return minmod(grad1, grad2);
    case 2:
      return vanleer(grad1, grad2);
    case 3:
      return vanalbada(grad1, grad2);
    case 4:
      return chakravarthy(grad1, grad2);
    case 5:
      return superbee(grad1, grad2);
    default:
      return -1;
    }
}
 
#endif