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;
}
}
These models have been particularly designed for use in the VoF solvers, both
incompressible and compressible. Currently constant and temperature dependent
surface tension models are provided but it easy to write models in which the
surface tension is evaluated from any fields held by the mesh database.
For example in the potentialFreeSurfaceFoam/oscillatingBox tutorial it is
cleaner to apply the "linearRamp" function to the "sine" function rather than
using an amplitude table:
floatingObject
{
type fixedNormalInletOutletVelocity;
fixTangentialInflow false;
normalVelocity
{
type uniformFixedValue;
uniformValue
{
type scale;
value
{
type sine;
frequency 1;
amplitude 0.025;
scale (0 1 0);
level (0 0 0);
}
scale
{
type linearRamp;
duration 10;
}
}
}
value uniform (0 0 0);
}
Description
Ramp function base class for the set of scalar functions starting from 0 and
increasing monotonically to 1 from \c start over the \c duration and
remaining at 1 thereafter.
Usage:
\verbatim
<entryName> <rampFunction>;
<entryName>Coeffs
{
start 10;
duration 20;
}
\endverbatim
or
\verbatim
<entryName>
{
type <rampFunction>;
start 10;
duration 20;
}
\endverbatim
Where:
\table
Property | Description | Required | Default value
start | Start time | no | 0
duration | Duration | yes |
\endtable
The following common ramp functions are provided: linear, quadratic, halfCosine,
quarterCosine and quaterSine, others can easily be added and registered to the run-time
selection system.
e.g.
ramp
{
type quadratic;
start 200;
duration 1.6;
}
but the old format is supported for backward compatibility:
ramp linear;
rampCoeffs
{
start 200;
duration 1.6;
}
Using
decomposePar -copyZero
The mesh is decomposed as usual but the '0' directory is recursively copied to
the 'processor.*' directories rather than decomposing the fields. This is a
convenient option to handle cases where the initial field files are generic and
can be used for serial or parallel running. See for example the
incompressible/simpleFoam/motorBike tutorial case.
Now the interFoam and compressibleInterFoam families of solvers use the same
alphaEqn formulation and supporting all of the MULES options without
code-duplication.
The semi-implicit MULES support allows running with significantly larger
time-steps but this does reduce the interface sharpness.
if convergence is not achieved within the maximum number of iterations.
Sometimes, particularly running in parallel, PBiCG fails to converge or diverges
without warning or obvious cause leaving a solution field containing significant
errors which can cause divergence of the application. PBiCGStab is more robust
and does not suffer from the problems encountered with PBiCG.
e.g. in tutorials/heatTransfer/buoyantSimpleFoam/externalCoupledCavity/0/T
hot
{
type externalCoupledTemperature;
commsDir "${FOAM_CASE}/comms";
file "data";
initByExternal yes;
log true;
value uniform 307.75; // 34.6 degC
}
Previously both 'file' and 'fileName' were used inconsistently in different
classes and given that there is no confusion or ambiguity introduced by using
the simpler 'file' rather than 'fileName' this change simplifies the use and
maintenance of OpenFOAM.
defined by functionObjects, e.g. wallHeatFlux, wallShearStress and yPlus.
Patch contributed by Bruno Santos
Resolves bug-report http://bugs.openfoam.org/view.php?id=2353
e.g. the motion of two counter-rotating AMI regions could be defined:
dynamicFvMesh dynamicMotionSolverListFvMesh;
solvers
(
rotor1
{
solver solidBody;
cellZone rotor1;
solidBodyMotionFunction rotatingMotion;
rotatingMotionCoeffs
{
origin (0 0 0);
axis (0 0 1);
omega 6.2832; // rad/s
}
}
rotor2
{
solver solidBody;
cellZone rotor2;
solidBodyMotionFunction rotatingMotion;
rotatingMotionCoeffs
{
origin (0 0 0);
axis (0 0 1);
omega -6.2832; // rad/s
}
}
);
Any combination of motion solvers may be selected but there is no special
handling of motion interaction; the motions are applied sequentially and
potentially cumulatively.
To support this new general framework the solidBodyMotionFvMesh and
multiSolidBodyMotionFvMesh dynamicFvMeshes have been converted into the
corresponding motionSolvers solidBody and multiSolidBody and the tutorials
updated to reflect this change e.g. the motion in the mixerVesselAMI2D tutorial
is now defined thus:
dynamicFvMesh dynamicMotionSolverFvMesh;
solver solidBody;
solidBodyCoeffs
{
cellZone rotor;
solidBodyMotionFunction rotatingMotion;
rotatingMotionCoeffs
{
origin (0 0 0);
axis (0 0 1);
omega 6.2832; // rad/s
}
}
- provides support for manipulating polyMesh/boundary
- changed behaviour of disableFunctionEntries option to preserve
#include
- dictionary: added reading of lists of dictionaries.
+ each list element may be accessed using the 'entryDDD' keyword
according to their list index.
Patch contributed by Mattijs Janssens
in which the reactions are enabled only in the specified list of
cellZones. e.g. in constant/combustionProperties
combustionModel zoneCombustion<psiChemistryCombustion>;
active true;
zoneCombustionCoeffs
{
zones (catalyst);
}
and in constant/zoneCombustionProperties
combustionModel laminar<psiChemistryCombustion>;
active true;
laminarCoeffs
{}
Corrected form of the Rosin-Rammler distribution taking into account the
varying number of particels per parces for for fixed-mass parcels. This
distribution should be used when
\verbatim
parcelBasisType mass;
\endverbatim
See equation 10 in reference:
\verbatim
Yoon, S. S., Hewson, J. C., DesJardin, P. E., Glaze, D. J.,
Black, A. R., & Skaggs, R. R. (2004).
Numerical modeling and experimental measurements of a high speed
solid-cone water spray for use in fire suppression applications.
International Journal of Multiphase Flow, 30(11), 1369-1388.
\endverbatim
