This fix changes how the intersections loop ignores previously
intersected faces. It now marks them by their index so that subsequent
iterations ignore them.
Before this change, after an intersection was found the start point was
advanced by a small amount to move the past the intersection. The
problem with this was if multiple boundary faces or the end point were
in close proximity to the intersection then the move forward might span
them. This could lead to intersections being missed or counted multiple
times, in some cases indefinitely.
Based on a patch contributed by Mattijs Janssens
Resolves bug report https://bugs.openfoam.org/view.php?id=1147
The projection direction has been corrected to include the effect of
mesh motion. The case where the source and receiving faces are of
differing orientations and the particle displacement points into both is
now detected and handled.
AMI interpolation is only ever constructed between sets of primitive
patches, so templating on the patch type is unnecessary. Templating in
this instance is undesirable; it makes type type/debug/selection system
more complex and increases the number and compilation times of files
which need recompiling when code is modified.
This is faster than the library functionality that it replaces, as it
allows the compiler to do inlining. It also does not utilise any static
state so generators do not interfere with each other. It is also faster
than the the array lookup in cachedRandom. The cachedRandom class
therefore offers no advantage over Random and has been removed.
Tree bound boxes are expanded asymmetrically to reduce the liklihood of
octree faces aliging with mesh faces and edges. The asymmetry is now
generated using hard-coded irrational numbers, rather than using a
random generator.
The asymmetry was effectively already hard coded. The random numbers are
only pseudo random, so the same numbers were being applied to the bound
boxes every time. This change simply removes the overhead of creating
the generator, and also gets rid of some duplicated code.
Sometimes decomposition can remove a cyclic patch entirely, converting
it into a processor cyclic. If this patch is being used to specify the
transform for a cyclicRepeatAMI patch then the calculation will fail.
This change adds a check for this situation, and errors with the
suggestion that the transform patch be preserved during decomposition.
A new constraint patch has been added which permits AMI coupling in
cyclic geometries. The coupling is repeated with different multiples of
the cyclic transformation in order to achieve a full correspondence.
This allows, for example, a cylindrical AMI interface to be used in a
sector of a rotational geometry.
The patch is used in a similar manner to cyclicAMI, except that it has
an additional entry, "transformPatch". This entry must name a coupled
patch. The transformation used to repeat the AMI coupling is taken from
this patch. For example, in system/blockMeshDict:
boundary
(
cyclic1
{
type cyclic;
neighbourPatch cyclic2;
faces ( ... );
}
cyclic2
{
type cyclic;
neighbourPatch cyclic1;
faces ( ... );
}
cyclicRepeatAMI1
{
type cyclicRepeatAMI;
neighbourPatch cyclicRepeatAM2;
transformPatch cyclic1;
faces ( ... );
}
cyclicRepeatAMI2
{
type cyclicRepeatAMI;
neighbourPatch cyclicRepeatAMI1;
transformPatch cyclic1;
faces ( ... );
}
// other patches ...
);
In this example, the transformation between cyclic1 and cyclic2 is used
to define the repetition used by the two cyclicRepeatAMI patches.
Whether cyclic1 or cyclic2 is listed as the transform patch is not
important.
A tutorial, incompressible/pimpleFoam/RAS/impeller, has been added to
demonstrate the functionality. This contains two repeating AMI pairs;
one cylindrical and one planar.
A significant amount of maintenance has been carried out on the AMI and
ACMI patches as part of this work. The AMI methods now return
dimensionless weights by default, which prevents ambiguity over the
units of the weight field during construction. Large amounts of
duplicate code have also been removed by deriving ACMI classes from
their AMI equivalents. The reporting and writing of AMI weights has also
been unified.
This work was supported by Dr Victoria Suponitsky, at General Fusion
Surfaces are specified as a list and the controls applied to each, e.g. in the
rhoPimpleFoam/RAS/annularThermalMixer tutorial:
surfaces
(
"AMI.obj"
"shaft.obj"
"wall.obj"
"statorBlades.obj"
"rotorBlades.obj"
);
includedAngle 150; // Identifes a feature when angle
// between faces < includedAngle
trimFeatures
{
minElem 10; // minimum edges within a feature
}
writeObj yes; // writes out _edgeMesh.obj files to view features
If different controls are required for different surfaces multiple
sub-dictionaries can be used:
AMIsurfaces
{
surfaces
(
"AMI.obj"
);
includedAngle 140; // Identifes a feature when angle
// between faces < includedAngle
trimFeatures
{
minElem 8; // minimum edges within a feature
}
writeObj yes; // writes out _edgeMesh.obj files to view features
}
otherSurfaces
{
surfaces
(
"shaft.obj"
"wall.obj"
"statorBlades.obj"
"rotorBlades.obj"
);
includedAngle 150; // Identifes a feature when angle
// between faces < includedAngle
trimFeatures
{
minElem 10; // minimum edges within a feature
}
writeObj yes; // writes out _edgeMesh.obj files to view features
}
Existing feature edge files corresponding to particular surfaces can be specified using
the "files" association list:
surfaces
(
"AMI.obj"
"shaft.obj"
"wall.obj"
"statorBlades.obj"
"rotorBlades.obj"
);
files
(
"AMI.obj" "constant/triSurface/AMI.obj.eMesh";
);
includedAngle 150; // Identifes a feature when angle
// between faces < includedAngle
trimFeatures
{
minElem 10; // minimum edges within a feature
}
writeObj yes; // writes out _edgeMesh.obj files to view features
For compatibility with all the mesh and related classes in OpenFOAM The 'normal'
function of the 'triangle', 'triFace' and 'face' classes now returns the unit
normal vector rather than the vector area which is now provided by the 'area'
function.
Specialized variants of the power law porosity and k epsilon turbulence models
developed to simulate atmospheric flow over forested and non-forested complex
terrain.
Class
Foam::powerLawLopesdaCosta
Description
Variant of the power law porosity model with spatially varying
drag coefficient
given by:
\f[
S = -\rho C_d \Sigma |U|^{(C_1 - 1)} U
\f]
where
\vartable
\Sigma | Porosity surface area per unit volume
C_d | Model linear coefficient
C_1 | Model exponent coefficient
\endvartable
Reference:
\verbatim
Costa, J. C. P. L. D. (2007).
Atmospheric flow over forested and non-forested complex terrain.
\endverbatim
Class
Foam::RASModels::kEpsilonLopesdaCosta
Description
Variant of the standard k-epsilon turbulence model with additional source
terms to handle the changes in turbulence in porous regions represented by
the powerLawLopesdaCosta porosity model.
Reference:
\verbatim
Costa, J. C. P. L. D. (2007).
Atmospheric flow over forested and non-forested complex terrain.
\endverbatim
The default model coefficients are
\verbatim
kEpsilonLopesdaCostaCoeffs
{
Cmu 0.09;
C1 1.44;
C2 1.92;
sigmak 1.0;
sigmaEps 1.3;
}
\endverbatim
Tutorial case to follow.
In early versions of OpenFOAM the scalar limits were simple macro replacements and the
names were capitalized to indicate this. The scalar limits are now static
constants which is a huge improvement on the use of macros and for consistency
the names have been changed to camel-case to indicate this and improve
readability of the code:
GREAT -> great
ROOTGREAT -> rootGreat
VGREAT -> vGreat
ROOTVGREAT -> rootVGreat
SMALL -> small
ROOTSMALL -> rootSmall
VSMALL -> vSmall
ROOTVSMALL -> rootVSmall
The original capitalized are still currently supported but their use is
deprecated.
First run the surfaceFeatureExtract with the "closeness" option enabled in the
surfaceFeatureExtractDict to extract the surface closeness point field
// Out put the closeness of surface elements to other surface elements.
closeness yes;
Then enable cell sizing based on local surface closeness by specifying the
"internalCloseness" options in the foamyHexMeshDict e.g.
motionControl
{
defaultCellSize 4;
minimumCellSizeCoeff 0.1;
maxSmoothingIterations 100;
maxRefinementIterations 2;
shapeControlFunctions
{
geometry
{
type searchableSurfaceControl;
priority 1;
mode inside;
surfaceCellSizeFunction nonUniformField;
cellSizeCalculationType automatic;
curvature false;
curvatureFile dummy;
featureProximity false;
featureProximityFile dummy;
internalCloseness true;
internalClosenessFile geometry.internalPointCloseness;
internalClosenessCellSizeCoeff 25;
curvatureCellSizeCoeff 0;
maximumCellSizeCoeff 1;
cellSizeFunction uniform;
}
}
}
The method used to calculate area overlaps between coupled AMI patches
has been made run-time selectable from the polyPatch dictionary. This
has primarily been done to facilitate the selection of the new swept AMI
method. The selection can be made within the constant/polyMesh/boundary
file as follows:
AMI1
{
type cyclicAMI;
inGroups 2(cyclicAMI rotating);
nFaces 524;
startFace 37176;
matchTolerance 0.0001;
transform unknown;
neighbourPatch AMI2;
method sweptFaceAreaWeightAMI; // <-- new entry
}
AMI2
{
type cyclicAMI;
inGroups 2(cyclicAMI rotating);
nFaces 524;
startFace 37700;
matchTolerance 0.0001;
transform unknown;
neighbourPatch AMI1;
method sweptFaceAreaWeightAMI; // <-- new entry
}
This can also be done within the patch specification section of the
blockMeshDict, or within a createBafflesDict.
The default remains the faceAreaWeightAMI method.
This method projects the source patch to the target using the point
normals. The projection fills space, which results in target weights
that correctly sum to unity. A source patch face can still project onto
an area larger or smaller than the face, so the source weights do not
(in general) sum to unity as a result of this method.
This has not been made the default AMI method. Further investigation is
needed to asses the benefits of this sort of projection.
The maximum walk angle determines the angle at which the face-face walk
stops. For some methods, this prevents calculation of overlaps on pairs
of faces which do not project on to each other. Derived AMI methods can
now override this angle as appropriate for their projection procedure.
The patch magSf calculation has been changed so that it uses the same
triangulation as the overlap algorithm. This improves consistency and
means that for exactly conforming patches (typically before any mesh
motion) the weights do not require normalisation.
When an OpenFOAM simulation runs in parallel, the data for decomposed fields and
mesh(es) has historically been stored in multiple files within separate
directories for each processor. Processor directories are named 'processorN',
where N is the processor number.
This commit introduces an alternative "collated" file format where the data for
each decomposed field (and mesh) is collated into a single file, which is
written and read on the master processor. The files are stored in a single
directory named 'processors'.
The new format produces significantly fewer files - one per field, instead of N
per field. For large parallel cases, this avoids the restriction on the number
of open files imposed by the operating system limits.
The file writing can be threaded allowing the simulation to continue running
while the data is being written to file. NFS (Network File System) is not
needed when using the the collated format and additionally, there is an option
to run without NFS with the original uncollated approach, known as
"masterUncollated".
The controls for the file handling are in the OptimisationSwitches of
etc/controlDict:
OptimisationSwitches
{
...
//- Parallel IO file handler
// uncollated (default), collated or masterUncollated
fileHandler uncollated;
//- collated: thread buffer size for queued file writes.
// If set to 0 or not sufficient for the file size threading is not used.
// Default: 2e9
maxThreadFileBufferSize 2e9;
//- masterUncollated: non-blocking buffer size.
// If the file exceeds this buffer size scheduled transfer is used.
// Default: 2e9
maxMasterFileBufferSize 2e9;
}
When using the collated file handling, memory is allocated for the data in the
thread. maxThreadFileBufferSize sets the maximum size of memory in bytes that
is allocated. If the data exceeds this size, the write does not use threading.
When using the masterUncollated file handling, non-blocking MPI communication
requires a sufficiently large memory buffer on the master node.
maxMasterFileBufferSize sets the maximum size in bytes of the buffer. If the
data exceeds this size, the system uses scheduled communication.
The installation defaults for the fileHandler choice, maxThreadFileBufferSize
and maxMasterFileBufferSize (set in etc/controlDict) can be over-ridden within
the case controlDict file, like other parameters. Additionally the fileHandler
can be set by:
- the "-fileHandler" command line argument;
- a FOAM_FILEHANDLER environment variable.
A foamFormatConvert utility allows users to convert files between the collated
and uncollated formats, e.g.
mpirun -np 2 foamFormatConvert -parallel -fileHandler uncollated
An example case demonstrating the file handling methods is provided in:
$FOAM_TUTORIALS/IO/fileHandling
The work was undertaken by Mattijs Janssens, in collaboration with Henry Weller.
"pos" now returns 1 if the argument is greater than 0, otherwise it returns 0.
This is consistent with the common mathematical definition of the "pos" function:
https://en.wikipedia.org/wiki/Sign_(mathematics)
However the previous implementation in which 1 was also returned for a 0
argument is useful in many situations so the "pos0" has been added which returns
1 if the argument is greater or equal to 0. Additionally the "neg0" has been
added which returns 1 if if the argument is less than or equal to 0.
now possible with level-sets as well as planes. Removed tetPoints class
as this wasn't really used anywhere except for the old tet-cutting
routines. Restored tetPointRef.H to be consistent with other primitive
shapes. Re-wrote tet-overlap mapping in terms of the new cutting.
