mapregion.h

Map Region

Map Region

Map a region of the domain with a Heaviside function. This function sets to 1 the cells containing the interface and the gas phase (the liquid phase if inverse). The number of layers defines how many layers of cells close to the interface, and belonging to the liquid phase, must be included (0 by default).

H: Heaviside function to be filled
f: Volume fraction field
nl: Number of layers to be included

#ifndef MAPREGION_H
#define MAPREGION_H

#ifndef F_ERR
# define F_ERR 1.e-10
#endif

void mapregion (
  scalar H,           // heaviside function
  scalar f,           // vof field (f = 1 if liquid)
  int nl = 0,         // number of additional layers (default 0, optional 1 or 2)
  int inverse = 0,    // the vof field if = 1 if gas (default false)
  int interface = 0)  // map just a narrow band around the interface (default false)
{
  scalar fc[];
  foreach()
    fc[] = (!inverse) ? f[] : 1. - f[];

  foreach() {
    if (interface)
      H[] = (fc[] > F_ERR && fc[] < 1.-F_ERR) ? 1. : 0.;
    else
      H[] = (fc[] < 1.-F_ERR) ? 1. : 0.;
    if (fc[] > 1.-F_ERR && nl > 0) {
      bool lightup = false;
      foreach_neighbor(nl) {
        if (fc[] > F_ERR && fc[] < 1.-F_ERR) {
          lightup = true;
          break;
        }
      }
      H[] = lightup ? 1. : 0.;
    }
  }
}

#endif