- input or output scaling of values to manage dissimilar unit systems
in the structures model
- logging of communicated force, moments and updated positions.
This allows tracking of the information exchange throughout the
duration of the simulation and may assist in post-simulation diagnosis.
- default is now without polyhedral decomposition, since this produces
compacter files and VTK mananges this in most instances.
However, provide function object flag to reinstate the old behaviour.
Calculates and outputs a field whose values are offset to a reference
value obtained by sampling the field at a user-specified location.
The field values are calculated using:
\f[
f_c = s(f_{c,t} - f_p + f_{off})
\f]
where
\vartable
f_c | field values at cell
s | optional scale factor (default = 1)
f_{c,t} | current field values at cell at this time
f_p | field value at position
f_{off} | offset field value (default = 0)
\endvartable
Usage
Example of function object specification to calculate the reference
field:
\verbatim
pRef
{
type reference;
libs ("libfieldFunctionObjects.so");
...
field p;
result pRef;
position (0 0 0);
scale 1.2;
offset 100000;
}
\endverbatim
- the problem arises since the various surface writers are stateless.
The collated output format hacks around this limitation by adding in
its own fieldDict caching (to disk).
Now include an updateMesh() method to hook into geometry changes.
This is considered a stop-gap measure until the surface output
handling is improved.
- improvement documentation for surface sampling.
- can now specify alternative sampling scheme for obtaining the
face values instead of just using the "cell" value. For example,
sampleScheme cellPoint;
This can be useful for cases when the surface is close to a boundary
cell and there are large gradients in the sampled field.
- distanceSurface now handles non-closed surfaces more robustly.
Unknown regions (not inside or outside) are marked internally and
excluded from consideration. This allows use of 'signed' surfaces
where not previously possible.
- a -valgrind option for logging with valgrind
- determine number of processors from system/decomposeParDict
or -decomposeParDict if -np was not specified
- this should normally not be triggered, provided that setRefCell was
used. However, if getRefCellValue() was called without any previous
checking on refCelli, it is possible to provoke errors.
Improvements to existing functionality
--------------------------------------
- MPI is initialised without thread support if it is not needed e.g. uncollated
- Use native c++11 threading; avoids problem with static destruction order.
- etc/cellModels now only read if needed.
- etc/controlDict can now be read from the environment variable FOAM_CONTROLDICT
- Uniform files (e.g. '0/uniform/time') are now read only once on the master only
(with the masterUncollated or collated file handlers)
- collated format writes to 'processorsNNN' instead of 'processors'. The file
format is unchanged.
- Thread buffer and file buffer size are no longer limited to 2Gb.
The global controlDict file contains parameters for file handling. Under some
circumstances, e.g. running in parallel on a system without NFS, the user may
need to set some parameters, e.g. fileHandler, before the global controlDict
file is read from file. To support this, OpenFOAM now allows the global
controlDict to be read as a string set to the FOAM_CONTROLDICT environment
variable.
The FOAM_CONTROLDICT environment variable can be set to the content the global
controlDict file, e.g. from a sh/bash shell:
export FOAM_CONTROLDICT=$(foamDictionary $FOAM_ETC/controlDict)
FOAM_CONTROLDICT can then be passed to mpirun using the -x option, e.g.:
mpirun -np 2 -x FOAM_CONTROLDICT simpleFoam -parallel
Note that while this avoids the need for NFS to read the OpenFOAM configuration
the executable still needs to load shared libraries which must either be copied
locally or available via NFS or equivalent.
New: Multiple IO ranks
----------------------
The masterUncollated and collated fileHandlers can now use multiple ranks for
writing e.g.:
mpirun -np 6 simpleFoam -parallel -ioRanks '(0 3)'
In this example ranks 0 ('processor0') and 3 ('processor3') now handle all the
I/O. Rank 0 handles 0,1,2 and rank 3 handles 3,4,5. The set of IO ranks should always
include 0 as first element and be sorted in increasing order.
The collated fileHandler uses the directory naming processorsNNN_XXX-YYY where
NNN is the total number of processors and XXX and YYY are first and last
processor in the rank, e.g. in above example the directories would be
processors6_0-2
processors6_3-5
and each of the collated files in these contains data of the local ranks
only. The same naming also applies when e.g. running decomposePar:
decomposePar -fileHandler collated -ioRanks '(0 3)'
New: Distributed data
---------------------
The individual root directories can be placed on different hosts with different
paths if necessary. In the current framework it is necessary to specify the
root per slave process but this has been simplified with the option of specifying
the root per host with the -hostRoots command line option:
mpirun -np 6 simpleFoam -parallel -ioRanks '(0 3)' \
-hostRoots '("machineA" "/tmp/" "machineB" "/tmp")'
The hostRoots option is followed by a list of machine name + root directory, the
machine name can contain regular expressions.
New: hostCollated
-----------------
The new hostCollated fileHandler automatically sets the 'ioRanks' according to
the host name with the lowest rank e.g. to run simpleFoam on 6 processors with
ranks 0-2 on machineA and ranks 3-5 on machineB with the machines specified in
the hostfile:
mpirun -np 6 --hostfile hostfile simpleFoam -parallel -fileHandler hostCollated
This is equivalent to
mpirun -np 6 --hostfile hostfile simpleFoam -parallel -fileHandler collated -ioRanks '(0 3)'
This example will write directories:
processors6_0-2/
processors6_3-5/
A typical example would use distributed data e.g. no two nodes, machineA and
machineB, each with three processes:
decomposePar -fileHandler collated -case cavity
# Copy case (constant/*, system/*, processors6/) to master:
rsync -a cavity machineA:/tmp/
# Create root on slave:
ssh machineB mkdir -p /tmp/cavity
# Run
mpirun --hostfile hostfile icoFoam \
-case /tmp/cavity -parallel -fileHandler hostCollated \
-hostRoots '("machineA" "/tmp" "machineB" "/tmp")'
Contributed by Mattijs Janssens
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.
- The iterator for a HashSet dereferences directly to its key.
- Eg,
for (const label patchi : patchSet)
{
...
}
vs.
forAllConstIter(labelHashSet, patchSet, iter)
{
const label patchi = iter.key();
...
}
- the algorithm was last used in OpenFOAM-2.4, after which it was
replaced with a FaceCellWave version.
Whereas the original (2.4.x) version exhibited performance
degradation on very large meshes (with explicit constraints), the
FaceCellWave version exhibited performance issues with large numbers
of blocked faces.
With large numbers of blocked faces, the FaceCellWave regionSplit
could take between 10 to 100 times longer due to the slow
propagation speed through blocked faces.
The 2.4 regionSplit has been revamped to avoid local memory
allocations, which appears to have been the source of the original
performance issues on large meshes.
For additional performance, intermediate renumbering is also avoided
during the consolidation of regions over processor domains.
- controlled by the the 'printExecutionFormat' InfoSwitch in
etc/controlDict
// Style for "ExecutionTime = " output
// - 0 = seconds (with trailing 's')
// - 1 = day-hh:mm:ss
ExecutionTime = 112135.2 s ClockTime = 113017 s
ExecutionTime = 1-07:08:55.20 ClockTime = 1-07:23:37
- Callable via the new Time::printExecutionTime() method,
which also helps to reduce clutter in the applications.
Eg,
runTime.printExecutionTime(Info);
vs
Info<< "ExecutionTime = " << runTime.elapsedCpuTime() << " s"
<< " ClockTime = " << runTime.elapsedClockTime() << " s"
<< nl << endl;
--
ENH: return elapsedClockTime() and clockTimeIncrement as double
- previously returned as time_t, which is less portable.
For example, with some HashTable or Map container of models
{ model0 => 1, model1 => 4, model2 => 5, model3 => 12, model4 => 15, }
specify the remapping
Map<label> mapper({{1, 3}, {2, 6}, {3, 12}, {5, 8}});
inplaceMapValue(mapper, models) then yields
{ model0 => 3, model1 => 4, model2 => 8, model3 => 12, model4 => 15, }
--
ENH: extend bitSet::count() to optionally count unset bits instead.
--
ENH: BitOps compatibility methods for boolList.
- These ease coding that uses a boolList instead of bitSet and use
short-circuit logic when possible.
Eg, when 'bitset' and 'bools' contain the same information
bitset.count() <-> BitOps::count(bools)
bitset.all() <-> BitOps::all(bools)
bitset.any() <-> BitOps::any(bools)
bitset.none() <-> BitOps::none(bools)
These methods can then be used directly in parameters or in logic.
Eg,
returnReduce(bitset.any(), orOp<bool>());
returnReduce(BitOps::any(bools), orOp<bool>());
if (BitOps::any(bools)) ...
