for consistency with the regionToCell topo set source and splitMeshRegions and
provides more logical extension to the multiple and outside point variants insidePoints,
outsidePoint and outsidePoints.
The FOAM file format has not changed from version 2.0 in many years and so there
is no longer a need for the 'version' entry in the FoamFile header to be
required and to reduce unnecessary clutter it is now optional, defaulting to the
current file format 2.0.
The inside or outside region refinement level is now specified using the simple
"level <level>" entry in refinementRegions e.g.
refinementRegions
{
refinementBox
{
mode inside;
level 5;
}
}
rather than
refinementRegions
{
refinementBox
{
mode inside;
levels ((1E15 5));
}
}
where the spurious "1E15" number is not used and the '((...))' is unnecessary clutter.
The closeness option in surfaceFeatures set in surfaceFeaturesDict, e.g.
closeness
{
// Output the closeness of surface points to other surface elements.
pointCloseness yes;
}
calculates and writes both the internal and external surface "closeness"
measures either of which could be used to set the span refinement in
snappyHexMesh depending on which side of the surface is being meshed which is
specified with either refinement mode "insideSpan" or "externalSpan", e.g. in
the tutorials/mesh/snappyHexMesh/pipe case the inside of the pipe is meshed and
refined based on the internal span using the following specification:
refinementRegions
{
pipeWall
{
mode insideSpan;
levels ((1000 2));
cellsAcrossSpan 40;
}
}
In the new tutorial mesh/snappyHexMesh/pipe the pipe diameter changes by a factor
of 2 but the number of cells across the pipe is specified to be constant along
the length using the new "span" refinement mode in which the number of cells
across the span is set to be at least 40:
refinementRegions
{
pipe
{
mode span;
levels ((1000 2)); // Maximum distance and maximum level
cellsAcrossSpan 40;
}
}
This operates in conjunction with the "pointCloseness" option in surfaceFeatures
which writes a surfacePointScalarField of the local span of the domain. Note
that the behaviour of this option is critically dependent on the quality of this
field and the surface may need to be re-triangulated more isotropically to
ensure the "pointCloseness" is accurate and representative of the domain and the
required mesh distribution.
