When using 'simple' or 'hierarchical' decomposition it is useful to slightly rotate a
coordinate-aligned block-mesh to improve the processor boundaries by avoiding
irregular cell distribution at those boundaries. The degree of slight rotation
is controlled by the 'delta' coefficient and a value of 0.001 is generally
suitable so to avoid unnecessary clutter in 'decomposeParDict' 'delta' now
defaults to this value.
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.
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.
Specifying a plane with which to subset feature edges is now done using
the same dictionary syntax used elsewhere in OpenFOAM. For example, in
system/surfaceFeaturesDict:
subsetFeatures
{
// Include only edges that intersect the plane
plane
{
planeType pointAndNormal;
point (0 0 0);
normal (1 0 0);
}
...
}
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.
End points of topoSet cylinder sources should now be specified as
"point1" and "point2", which is consistent with other parts of the code.
The previous keywords, "p1" and "p2" have been retained for backwards
compatibility but may be removed in future.
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;
}
}
To handle the additional optional specification for the closeness calculation
these settings are now is a sub-dictionary of surfaceFeaturesDict, e.g.
closeness
{
// Output the closeness of surface elements to other surface elements.
faceCloseness no;
// Output the closeness of surface points to other surface elements.
pointCloseness yes;
// Optional maximum angle between opposite points considered close
internalAngleTolerance 80;
externalAngleTolerance 80;
}
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.
A surface geometry file should be stored in
$FOAM_TUTORIALS/resources/geometry if it is used in multiple cases,
otherwise it should be stored locally to the case. This change enforces
that across all tutorials.
which are now read directly from the thermophysicalProperties dictionary for
consistency with non-reacting mixture thermodynamics. The species thermo and
reactions lists can still be in separate files if convenient and included into
the thermophysicalProperties file using the standard dictionary #include.
Now for transient simulations "Final" solver settings are required for ALL
equations providing consistency between the solution of velocity, energy,
composition and radiation properties.
However "Final" relaxation factors are no longer required for fields or
equations and if not present the standard value for the variable will be
applied. Given that relaxation factors other than 1 are rarely required for
transient runs and hence the same for all iterations including the final one
this approach provide simpler input while still providing the flexibility to
specify a different value for the final iteration if required. For steady cases
it is usual to execute just 1 outer iteration per time-step for which the
standard relaxation factors are appropriate, and if more than one iteration is
executed it is common to use the same factors for both. In the unlikely event
of requiring different relaxation factors for the final iteration this is still
possible to specify via the now optional "Final" specification.
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.
The new optional switch 'writeCyclicMatch' can be set to 'true' to enable the writing of
the cyclic match OBJ files; defaults to 'false'.
Patch contributed by Bruno Santos
Resolves patch request https://bugs.openfoam.org/view.php?id=2685
except turbulence and lagrangian which will also be updated shortly.
For example in the nonNewtonianIcoFoam offsetCylinder tutorial the viscosity
model coefficients may be specified in the corresponding "<type>Coeffs"
sub-dictionary:
transportModel CrossPowerLaw;
CrossPowerLawCoeffs
{
nu0 [0 2 -1 0 0 0 0] 0.01;
nuInf [0 2 -1 0 0 0 0] 10;
m [0 0 1 0 0 0 0] 0.4;
n [0 0 0 0 0 0 0] 3;
}
BirdCarreauCoeffs
{
nu0 [0 2 -1 0 0 0 0] 1e-06;
nuInf [0 2 -1 0 0 0 0] 1e-06;
k [0 0 1 0 0 0 0] 0;
n [0 0 0 0 0 0 0] 1;
}
which allows a quick change between models, or using the simpler
transportModel CrossPowerLaw;
nu0 [0 2 -1 0 0 0 0] 0.01;
nuInf [0 2 -1 0 0 0 0] 10;
m [0 0 1 0 0 0 0] 0.4;
n [0 0 0 0 0 0 0] 3;
if quick switching between models is not required.
To support this more convenient parameter specification the inconsistent
specification of seedSampleSet in the streamLine and wallBoundedStreamLine
functionObjects had to be corrected from
// Seeding method.
seedSampleSet uniform; //cloud; //triSurfaceMeshPointSet;
uniformCoeffs
{
type uniform;
axis x; //distance;
// Note: tracks slightly offset so as not to be on a face
start (-1.001 -0.05 0.0011);
end (-1.001 -0.05 1.0011);
nPoints 20;
}
to the simpler
// Seeding method.
seedSampleSet
{
type uniform;
axis x; //distance;
// Note: tracks slightly offset so as not to be on a face
start (-1.001 -0.05 0.0011);
end (-1.001 -0.05 1.0011);
nPoints 20;
}
which also support the "<type>Coeffs" form
// Seeding method.
seedSampleSet
{
type uniform;
uniformCoeffs
{
axis x; //distance;
// Note: tracks slightly offset so as not to be on a face
start (-1.001 -0.05 0.0011);
end (-1.001 -0.05 1.0011);
nPoints 20;
}
}
