static void init_fd (FttCellFace * face, FaceInitData * fd)
{
if (face->d % 2 != 0)
GFS_VALUE (face->cell, fd->v2) = gfs_function_face_value (fd->f, face);
else
GFS_VALUE (face->cell, fd->v1) = gfs_function_face_value (fd->f, face);
}
static void poisson_coeff_por (FttCellFace * face,
PoissonCoeff_por * p)
{
gdouble alpha = p->alpha ? (gfs_function_face_value (p->alpha, face)*gfs_function_face_value (p->phi, face)) : gfs_function_face_value (p->phi, face);
gdouble v = p->lambda2[face->d/2]*alpha*gfs_domain_face_fraction (p->domain, face)/
gfs_domain_face_scale_metric (p->domain, face, face->d/2);
if (alpha <= 0. && p->positive) {
FttVector p;
ftt_face_pos (face, &p);
g_log (G_LOG_DOMAIN, G_LOG_LEVEL_ERROR,
"alpha is negative (%g) at face (%g,%g,%g).\n"
"Please check your definition.",
alpha, p.x, p.y, p.z);
}
GFS_STATE (face->cell)->f[face->d].v += v;
switch (ftt_face_type (face)) {
case FTT_FINE_FINE:
GFS_STATE (face->neighbor)->f[FTT_OPPOSITE_DIRECTION (face->d)].v += v;
break;
case FTT_FINE_COARSE:
GFS_STATE (face->neighbor)->f[FTT_OPPOSITE_DIRECTION (face->d)].v +=
v/FTT_CELLS_DIRECTION (face->d);
break;
default:
g_assert_not_reached ();
}
}
static void diffusion_term (FttCell * cell, DataDif * data)
{
/* fixme: I need to account for the metric */
gdouble size, sizenext, size_ratio;
gdouble un, unext, unprev;
FttDirection d0;
for (d0 = 0; d0 < FTT_NEIGHBORS; d0++) {
FttCellFace face = gfs_cell_face(cell, d0);
gdouble flux = 0.;
gdouble invdens = data->alpha ? gfs_function_face_value (data->alpha, &face) : 1.;
gdouble visc = gfs_diffusion_cell (data->d->D, cell);
GfsStateVector * s = GFS_STATE (cell);
FttDirection od = FTT_OPPOSITE_DIRECTION(d0);
un = interpolate_value_skew (cell, d0, NULL, data->fd);
if ((d0 % 2) != 0) {
unext = interpolate_value_skew (cell, od , NULL, data->fd);
unprev = interpolate_value_skew (cell, d0 , &(d0) , data->fd);
sizenext = ftt_cell_size (cell);
size = get_size_next (cell, d0);
}
else {
unext = interpolate_value_skew (cell, d0, &(d0), data->fd);
unprev = interpolate_value_skew (cell, od, NULL, data->fd);
size = ftt_cell_size (cell);
sizenext = get_size_next (cell, d0);
}
size_ratio = ( 1. + sizenext / size ) / 2;
flux = ( (unext - un)/sizenext - (un - unprev)/size );
FttComponent c = d0/2;
#if FTT_2D
FttComponent oc = FTT_ORTHOGONAL_COMPONENT (c);
flux += size_ratio * transverse_diffusion(cell, oc, d0, un, data->fd);
#else
static FttComponent orthogonal[FTT_DIMENSION][2] = {
{FTT_Y, FTT_Z}, {FTT_X, FTT_Z}, {FTT_X, FTT_Y}
};
flux += size_ratio * transverse_diffusion(cell, orthogonal[c][0], d0, un, data->fd);
flux += size_ratio * transverse_diffusion(cell, orthogonal[c][1], d0, un, data->fd);
#endif
s->f[d0].v -= invdens*visc*flux;
}
}
