It is not clear for what cases the minVol control is useful or necessary and for
some cases it causes problems with snapping and layer addition if not set to a
sufficiently small value.
motionSmootherAlgoCheck::checkMesh is used by snappyHexMesh to check the mesh
after snapping and morphing. The minVol test which checks for collapsed cells
is now relative to the cube of the minimum bounding box length so that it is
less dependent on the size of the geometry and less likely to need changing for
very small geometries.
The default value is set in
etc/caseDicts/mesh/generation/meshQualityDict
etc/caseDicts/mesh/generation/meshQualityDict.cfg
//- Minimum cell pyramid volume relative to min bounding box length^3
// Set to a fraction of the smallest cell volume expected.
// Set to very negative number (e.g. -1e30) to disable.
minVol 1e-10;
The unused minArea and minTriangleTwist tests have been removed
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.
and only needed if there is a name clash between entries in the source
specification and the set specification, e.g. "name":
{
name rotorCells;
type cellSet;
action new;
source zoneToCell;
sourceInfo
{
name cylinder;
}
}
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 previous naming tan1, tan2, normal was non-intuitive and very confusing.
It was not practical to maintain backward compatibility but all tutorials and
example refineMeshDict files have been updated to provide examples of the
change.
Originally the only supported geometry specification were triangulated surfaces,
hence the name of the directory: constant/triSurface, however now that other
surface specifications are supported and provided it is much more logical that
the directory is named accordingly: constant/geometry. All tutorial and
template cases have been updated.
Note that backward compatibility is provided such that if the constant/geometry
directory does not exist but constant/triSurface does then the geometry files
are read from there.
A new run-time selectable interface compression scheme framework has been added
to the two-phase VoF solvers to provide greater flexibility, extensibility and
more consistent user-interface. The previously built-in interface compression
is now in the standard run-time selectable surfaceInterpolationScheme
interfaceCompression:
Class
Foam::interfaceCompression
Description
Interface compression corrected scheme, based on counter-gradient
transport, to maintain sharp interfaces during VoF simulations.
The interface compression is applied to the face interpolated field from a
suitable 2nd-order shape-preserving NVD or TVD scheme, e.g. vanLeer or
vanAlbada. A coefficient is supplied to control the degree of compression,
with a value of 1 suitable for most VoF cases to ensure interface integrity.
A value larger than 1 can be used but the additional compression can bias
the interface to follow the mesh more closely while a value smaller than 1
can lead to interface smearing.
Example:
\verbatim
divSchemes
{
.
.
div(phi,alpha) Gauss interfaceCompression vanLeer 1;
.
.
}
\endverbatim
The separate scheme for the interface compression term "div(phirb,alpha)" is no
longer required or used nor is the compression coefficient cAlpha in fvSolution
as this is now part of the "div(phi,alpha)" scheme specification as shown above.
Backward-compatibility is provided by checking the specified "div(phi,alpha)"
scheme against the known interface compression schemes and if it is not one of
those the new interfaceCompression scheme is used with the cAlpha value
specified in fvSolution.
More details can be found here:
https://cfd.direct/openfoam/free-software/multiphase-interface-capturing
Henry G. Weller
CFD Direct Ltd.
These cases now check for a mesh in geometrically identical cases and
copy rather than re-generate if possible. This reduces the run-time of
the test loop by about 20 minutes.
and replaced interDyMFoam with a script which reports this change.
The interDyMFoam tutorials have been moved into the interFoam directory.
This change is one of a set of developments to merge dynamic mesh functionality
into the standard solvers to improve consistency, usability, flexibility and
maintainability of these solvers.
Henry G. Weller
CFD Direct Ltd.
