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;
}
}
by combining with and rationalizing functionality from
turbulentHeatFluxTemperatureFvPatchScalarField.
externalWallHeatFluxTemperatureFvPatchScalarField now replaces
turbulentHeatFluxTemperatureFvPatchScalarField which is no longer needed and has
been removed.
Description
This boundary condition applies a heat flux condition to temperature
on an external wall in one of three modes:
- fixed power: supply Q
- fixed heat flux: supply q
- fixed heat transfer coefficient: supply h and Ta
where:
\vartable
Q | Power [W]
q | Heat flux [W/m^2]
h | Heat transfer coefficient [W/m^2/K]
Ta | Ambient temperature [K]
\endvartable
For heat transfer coefficient mode optional thin thermal layer resistances
can be specified through thicknessLayers and kappaLayers entries.
The thermal conductivity \c kappa can either be retrieved from various
possible sources, as detailed in the class temperatureCoupledBase.
Usage
\table
Property | Description | Required | Default value
mode | 'power', 'flux' or 'coefficient' | yes |
Q | Power [W] | for mode 'power' |
q | Heat flux [W/m^2] | for mode 'flux' |
h | Heat transfer coefficient [W/m^2/K] | for mode 'coefficent' |
Ta | Ambient temperature [K] | for mode 'coefficient' |
thicknessLayers | Layer thicknesses [m] | no |
kappaLayers | Layer thermal conductivities [W/m/K] | no |
qr | Name of the radiative field | no | none
qrRelaxation | Relaxation factor for radiative field | no | 1
kappaMethod | Inherited from temperatureCoupledBase | inherited |
kappa | Inherited from temperatureCoupledBase | inherited |
\endtable
Example of the boundary condition specification:
\verbatim
<patchName>
{
type externalWallHeatFluxTemperature;
mode coefficient;
Ta uniform 300.0;
h uniform 10.0;
thicknessLayers (0.1 0.2 0.3 0.4);
kappaLayers (1 2 3 4);
kappaMethod fluidThermo;
value $internalField;
}
\endverbatim
snappyHexMesh produces a far better quality AMI interface using a cylindrical background mesh,
leading to much more robust performance, even on a relatively coarse mesh. The min/max AMI
weights remain close to 1 as the mesh moves, giving better conservation.
The rotating geometry template cases are configured with a blockMeshDict file for a cylindrical
background mesh aligned along the z-axis. The details of use are found in the README and
blockMeshDict files.
Uncommenting the patches provides a convenient way to use the patches in the background mesh
to define the external boundary of the final mesh. Replaces previous setup with a separate
blockMeshDict.extPatches file.
rhoSimpleFoam now instantiates the lower-level fluidThermo which instantiates
either a psiThermo or rhoThermo according to the 'type' specification in
thermophysicalProperties, e.g.
thermoType
{
type hePsiThermo;
mixture pureMixture;
transport sutherland;
thermo janaf;
equationOfState perfectGas;
specie specie;
energy sensibleInternalEnergy;
}
instantiates a psiThermo for a perfect gas with JANAF thermodynamics, whereas
thermoType
{
type heRhoThermo;
mixture pureMixture;
properties liquid;
energy sensibleInternalEnergy;
}
mixture
{
H2O;
}
instantiates a rhoThermo for water, see new tutorial
compressible/rhoSimpleFoam/squareBendLiq.
In order to support complex equations of state the pressure can no longer be
unlimited and rhoSimpleFoam now limits the pressure rather than the density to
handle start-up more robustly.
For backward compatibility 'rhoMin' and 'rhoMax' can still be used in the SIMPLE
sub-dictionary of fvSolution which are converted into 'pMax' and 'pMin' but it
is better to set either 'pMax' and 'pMin' directly or use the more convenient
'pMinFactor' and 'pMinFactor' from which 'pMax' and 'pMin' are calculated using
the fixed boundary pressure or reference pressure e.g.
SIMPLE
{
nNonOrthogonalCorrectors 0;
pMinFactor 0.1;
pMaxFactor 1.5;
transonic yes;
consistent yes;
residualControl
{
p 1e-3;
U 1e-4;
e 1e-3;
"(k|epsilon|omega)" 1e-3;
}
}
The fundamental properties provided by the specie class hierarchy were
mole-based, i.e. provide the properties per mole whereas the fundamental
properties provided by the liquidProperties and solidProperties classes are
mass-based, i.e. per unit mass. This inconsistency made it impossible to
instantiate the thermodynamics packages (rhoThermo, psiThermo) used by the FV
transport solvers on liquidProperties. In order to combine VoF with film and/or
Lagrangian models it is essential that the physical propertied of the three
representations of the liquid are consistent which means that it is necessary to
instantiate the thermodynamics packages on liquidProperties. This requires
either liquidProperties to be rewritten mole-based or the specie classes to be
rewritten mass-based. Given that most of OpenFOAM solvers operate
mass-based (solve for mass-fractions and provide mass-fractions to sub-models it
is more consistent and efficient if the low-level thermodynamics is also
mass-based.
This commit includes all of the changes necessary for all of the thermodynamics
in OpenFOAM to operate mass-based and supports the instantiation of
thermodynamics packages on liquidProperties.
Note that most users, developers and contributors to OpenFOAM will not notice
any difference in the operation of the code except that the confusing
nMoles 1;
entries in the thermophysicalProperties files are no longer needed or used and
have been removed in this commet. The only substantial change to the internals
is that species thermodynamics are now "mixed" with mass rather than mole
fractions. This is more convenient except for defining reaction equilibrium
thermodynamics for which the molar rather than mass composition is usually know.
The consequence of this can be seen in the adiabaticFlameT, equilibriumCO and
equilibriumFlameT utilities in which the species thermodynamics are
pre-multiplied by their molecular mass to effectively convert them to mole-basis
to simplify the definition of the reaction equilibrium thermodynamics, e.g. in
equilibriumCO
// Reactants (mole-based)
thermo FUEL(thermoData.subDict(fuelName)); FUEL *= FUEL.W();
// Oxidant (mole-based)
thermo O2(thermoData.subDict("O2")); O2 *= O2.W();
thermo N2(thermoData.subDict("N2")); N2 *= N2.W();
// Intermediates (mole-based)
thermo H2(thermoData.subDict("H2")); H2 *= H2.W();
// Products (mole-based)
thermo CO2(thermoData.subDict("CO2")); CO2 *= CO2.W();
thermo H2O(thermoData.subDict("H2O")); H2O *= H2O.W();
thermo CO(thermoData.subDict("CO")); CO *= CO.W();
// Product dissociation reactions
thermo CO2BreakUp
(
CO2 == CO + 0.5*O2
);
thermo H2OBreakUp
(
H2O == H2 + 0.5*O2
);
Please report any problems with this substantial but necessary rewrite of the
thermodynamic at https://bugs.openfoam.org
Henry G. Weller
CFD Direct Ltd.
which provided warning about backward-compatibility issue with setting div
schemes for steady-state. It caused confusion by generating incorrect warning
messages for compressible cases for which the 'bounded' should NOT be applied to
the 'div(phid,p)'.
- "$FOAM_USER_APPBIN" and "$FOAM_USER_LIBBIN" have been added to
"foamOldDirs" in "etc/bashrc" and "etc/config.sh/unset"
- "$OPAL_PREFIX" is now undefined in the option "SYSTEMOPENMPI" within
"etc/config.sh/mpi", but only if the path defined in this variable
is cleaned when using "foamCleanPath".
- "$OPAL_PREFIX" is now also conditionally undefined in
"etc/config.sh/unset" when the path is picked up by "foamCleanPath".
Patch contributed by Bruno Santos
Resolved bug-report http://bugs.openfoam.org/view.php?id=2210
The change from C++0x to C++11 allows all of C++11 functionality to be
used in OpenFOAM, in particular constructor delegation which avoids code
duplication or constructor helper functions. However, this also means a
change to the minimum gcc version supported which is now 4.7 rather than
4.5.
Note that gcc-4.7 does not support the entire C++11 standard but does
support all of the functionality currently needed for further OpenFOAM
development. The minimum gcc-version which supports the entire C++11
standard is 4.8 which is now the recommended minimum gcc version.
