The streamLines function object now writes out "age" by default. This is
calculated as the total integration time from the starting point of the
streamline. This value can be negative if tracking is performed in the
reverse direction. Writing "age" can be deactivated by means of a
"writeAge no;" entry in the function object specification.
The standard set of Lagrangian clouds are now selectable at run-time.
This means that a solver that supports Lagrangian modelling can now use
any type of cloud (with some restrictions). Previously, solvers were
hard-coded to use specific cloud modelling. In addition, a cloud-list
structure has been added so that solvers may select multiple clouds,
rather than just one.
The new system is controlled as follows:
- If only a single cloud is required, then the settings for the
Lagrangian modelling should be placed in a constant/cloudProperties
file.
- If multiple clouds are required, then a constant/clouds file should be
created containing a list of cloud names defined by the user. Each
named cloud then reads settings from a corresponding
constant/<cloudName>Properties file. Clouds are evolved sequentially
in the order in which they are listed in the constant/clouds file.
- If no clouds are required, then the constant/cloudProperties file and
constant/clouds file should be omitted.
The constant/cloudProperties or constant/<cloudName>Properties files are
the same as previous cloud properties files; e.g.,
constant/kinematicCloudProperties or constant/reactingCloud1Properties,
except that they now also require an additional top-level "type" entry
to select which type of cloud is to be used. The available options for
this entry are:
type cloud; // A basic cloud of solid
// particles. Includes forces,
// patch interaction, injection,
// dispersion and stochastic
// collisions. Same as the cloud
// previously used by
// rhoParticleFoam
// (uncoupledKinematicParticleFoam)
type collidingCloud; // As "cloud" but with resolved
// collision modelling. Same as the
// cloud previously used by DPMFoam
// and particleFoam
// (icoUncoupledKinematicParticleFoam)
type MPPICCloud; // As "cloud" but with MPPIC
// collision modelling. Same as the
// cloud previously used by
// MPPICFoam.
type thermoCloud; // As "cloud" but with
// thermodynamic modelling and heat
// transfer with the carrier phase.
// Same as the limestone cloud
// previously used by
// coalChemistryFoam.
type reactingCloud; // As "thermoCloud" but with phase
// change and mass transfer
// coupling with the carrier
// phase. Same as the cloud
// previously used in fireFoam.
type reactingMultiphaseCloud; // As "reactingCloud" but with
// particles that contain multiple
// phases. Same as the clouds
// previously used in
// reactingParcelFoam and
// simpleReactingParcelFoam and the
// coal cloud used in
// coalChemistryFoam.
type sprayCloud; // As "reactingCloud" but with
// additional spray-specific
// collision and breakup modelling.
// Same as the cloud previously
// used in sprayFoam and
// engineFoam.
The first three clouds are not thermally coupled, so are available in
all Lagrangian solvers. The last four are thermally coupled and require
access to the carrier thermodynamic model, so are only available in
compressible Lagrangian solvers.
This change has reduced the number of solvers necessary to provide the
same functionality; solvers that previously differed only in their
Lagrangian modelling can now be combined. The Lagrangian solvers have
therefore been consolidated with consistent naming as follows.
denseParticleFoam: Replaces DPMFoam and MPPICFoam
reactingParticleFoam: Replaces sprayFoam and coalChemistryFoam
simpleReactingParticleFoam: Replaces simpleReactingParcelFoam
buoyantReactingParticleFoam: Replaces reactingParcelFoam
fireFoam and engineFoam remain, although fireFoam is likely to be merged
into buoyantReactingParticleFoam in the future once the additional
functionality it provides is generalised.
Some additional minor functionality has also been added to certain
solvers:
- denseParticleFoam has a "cloudForceSplit" control which can be set in
system/fvOptions.PIMPLE. This provides three methods for handling the
cloud momentum coupling, each of which have different trade-off-s
regarding numerical artefacts in the velocity field. See
denseParticleFoam.C for more information, and also bug report #3385.
- reactingParticleFoam and buoyantReactingParticleFoam now support
moving mesh in order to permit sharing parts of their implementation
with engineFoam.
Currently these deleted function declarations are still in the private section
of the class declarations but will be moved by hand to the public section over
time as this is too complex to automate reliably.
Replaced all uses of complex Xfer class with C++11 "move" constructors and
assignment operators. Removed the now redundant Xfer class.
This substantial changes improves consistency between OpenFOAM and the C++11 STL
containers and algorithms, reduces memory allocation and copy overhead when
returning containers from functions and simplifies maintenance of the core
libraries significantly.
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.
Streamlines can now be tracked in both directions from the set of
initial locations. The keyword controlling this behaviour is
"direction", which can be set to "forward", "backward" or "both".
This new keyword superseeds the "trackForward" entry, which has been
retained for backwards compatibility.
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.
A lot of methods were taking argument data which could be referenced or
generated from the parcel class at little or no additional cost. This
was confusing and generated the possibility of inconsistent data states.
Tracking data classes are no longer templated on the derived cloud type.
The advantage of this is that they can now be passed to sub models. This
should allow continuous phase data to be removed from the parcel
classes. The disadvantage is that every function which once took a
templated TrackData argument now needs an additional TrackCloudType
argument in order to perform the necessary down-casting.
Particle collisions with ACMI patches are now handled. The hit detects
whether the location is within the overlap or the coupled region and
recurses, calling the hit routine appropriate for the region.
The low level tracking methods are now more consistently named. There is
now a distinction between tracking to a face and hitting it. Function
object side effects have been moved out of the base layer and into the
parcels on which they are meaningful.
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.
terms of the local barycentric coordinates of the current tetrahedron,
rather than the global coordinate system.
Barycentric tracking works on any mesh, irrespective of mesh quality.
Particles do not get "lost", and tracking does not require ad-hoc
"corrections" or "rescues" to function robustly, because the calculation
of particle-face intersections is unambiguous and reproducible, even at
small angles of incidence.
Each particle position is defined by topology (i.e. the decomposed tet
cell it is in) and geometry (i.e. where it is in the cell). No search
operations are needed on restart or reconstruct, unlike when particle
positions are stored in the global coordinate system.
The particle positions file now contains particles' local coordinates
and topology, rather than the global coordinates and cell. This change
to the output format is not backwards compatible. Existing cases with
Lagrangian data will not restart, but they will still run from time
zero without any modification. This change was necessary in order to
guarantee that the loaded particle is valid, and therefore
fundamentally prevent "loss" and "search-failure" type bugs (e.g.,
2517, 2442, 2286, 1836, 1461, 1341, 1097).
The tracking functions have also been converted to function in terms
of displacement, rather than end position. This helps remove floating
point error issues, particularly towards the end of a tracking step.
Wall bounded streamlines have been removed. The implementation proved
incompatible with the new tracking algorithm. ParaView has a surface
LIC plugin which provides equivalent, or better, functionality.
Additionally, bug report <https://bugs.openfoam.org/view.php?id=2517>
is resolved by this change.
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;
}
}
Replaced the 'postProcess' argument to the 'write' and 'execute'
functions with the single static member 'postProcess' in the
functionObject base-class.
with the more general and flexible 'postProcess' utility and '-postProcess' solver option
Rationale
---------
Both the 'postProcess' utility and '-postProcess' solver option use the
same extensive set of functionObjects available for data-processing
during the run avoiding the substantial code duplication necessary for
the 'foamCalc' and 'postCalc' utilities and simplifying maintenance.
Additionally consistency is guaranteed between solver data processing
and post-processing.
The functionObjects have been substantially re-written and generalized
to simplify development and encourage contribution.
Configuration
-------------
An extensive set of simple functionObject configuration files are
provided in
OpenFOAM-dev/etc/caseDicts/postProcessing
and more will be added in the future. These can either be copied into
'<case>/system' directory and included into the 'controlDict.functions'
sub-dictionary or included directly from 'etc/caseDicts/postProcessing'
using the '#includeEtc' directive or the new and more convenient
'#includeFunc' directive which searches the
'<etc>/caseDicts/postProcessing' directories for the selected
functionObject, e.g.
functions
{
#includeFunc Q
#includeFunc Lambda2
}
'#includeFunc' first searches the '<case>/system' directory in case
there is a local configuration.
Description of #includeFunc
---------------------------
Specify a functionObject dictionary file to include, expects the
functionObject name to follow (without quotes).
Search for functionObject dictionary file in
user/group/shipped directories.
The search scheme allows for version-specific and
version-independent files using the following hierarchy:
- \b user settings:
- ~/.OpenFOAM/\<VERSION\>/caseDicts/postProcessing
- ~/.OpenFOAM/caseDicts/postProcessing
- \b group (site) settings (when $WM_PROJECT_SITE is set):
- $WM_PROJECT_SITE/\<VERSION\>/caseDicts/postProcessing
- $WM_PROJECT_SITE/caseDicts/postProcessing
- \b group (site) settings (when $WM_PROJECT_SITE is not set):
- $WM_PROJECT_INST_DIR/site/\<VERSION\>/caseDicts/postProcessing
- $WM_PROJECT_INST_DIR/site/caseDicts/postProcessing
- \b other (shipped) settings:
- $WM_PROJECT_DIR/etc/caseDicts/postProcessing
An example of the \c \#includeFunc directive:
\verbatim
#includeFunc <funcName>
\endverbatim
postProcess
-----------
The 'postProcess' utility and '-postProcess' solver option provide the
same set of controls to execute functionObjects after the run either by
reading a specified set of fields to process in the case of
'postProcess' or by reading all fields and models required to start the
run in the case of '-postProcess' for each selected time:
postProcess -help
Usage: postProcess [OPTIONS]
options:
-case <dir> specify alternate case directory, default is the cwd
-constant include the 'constant/' dir in the times list
-dict <file> read control dictionary from specified location
-field <name> specify the name of the field to be processed, e.g. U
-fields <list> specify a list of fields to be processed, e.g. '(U T p)' -
regular expressions not currently supported
-func <name> specify the name of the functionObject to execute, e.g. Q
-funcs <list> specify the names of the functionObjects to execute, e.g.
'(Q div(U))'
-latestTime select the latest time
-newTimes select the new times
-noFunctionObjects
do not execute functionObjects
-noZero exclude the '0/' dir from the times list, has precedence
over the -withZero option
-parallel run in parallel
-region <name> specify alternative mesh region
-roots <(dir1 .. dirN)>
slave root directories for distributed running
-time <ranges> comma-separated time ranges - eg, ':10,20,40:70,1000:'
-srcDoc display source code in browser
-doc display application documentation in browser
-help print the usage
pimpleFoam -postProcess -help
Usage: pimpleFoam [OPTIONS]
options:
-case <dir> specify alternate case directory, default is the cwd
-constant include the 'constant/' dir in the times list
-dict <file> read control dictionary from specified location
-field <name> specify the name of the field to be processed, e.g. U
-fields <list> specify a list of fields to be processed, e.g. '(U T p)' -
regular expressions not currently supported
-func <name> specify the name of the functionObject to execute, e.g. Q
-funcs <list> specify the names of the functionObjects to execute, e.g.
'(Q div(U))'
-latestTime select the latest time
-newTimes select the new times
-noFunctionObjects
do not execute functionObjects
-noZero exclude the '0/' dir from the times list, has precedence
over the -withZero option
-parallel run in parallel
-postProcess Execute functionObjects only
-region <name> specify alternative mesh region
-roots <(dir1 .. dirN)>
slave root directories for distributed running
-time <ranges> comma-separated time ranges - eg, ':10,20,40:70,1000:'
-srcDoc display source code in browser
-doc display application documentation in browser
-help print the usage
The functionObjects to execute may be specified on the command-line
using the '-func' option for a single functionObject or '-funcs' for a
list, e.g.
postProcess -func Q
postProcess -funcs '(div(U) div(phi))'
In the case of 'Q' the default field to process is 'U' which is
specified in and read from the configuration file but this may be
overridden thus:
postProcess -func 'Q(Ua)'
as is done in the example above to calculate the two forms of the divergence of
the velocity field. Additional fields which the functionObjects may depend on
can be specified using the '-field' or '-fields' options.
The 'postProcess' utility can only be used to execute functionObjects which
process fields present in the time directories. However, functionObjects which
depend on fields obtained from models, e.g. properties derived from turbulence
models can be executed using the '-postProcess' of the appropriate solver, e.g.
pisoFoam -postProcess -func PecletNo
or
sonicFoam -postProcess -func MachNo
In this case all required fields will have already been read so the '-field' or
'-fields' options are not be needed.
Henry G. Weller
CFD Direct Ltd.
