Coded functionality now supports basic un-typed substitutions from the
surrounding dictionary. For example:
value 1.2345;
#codeExecute
{
scalar s = $value;
...
};
It also now supports the more functional typed substitutions, such as:
direction (1 0 0);
#codeExecute
{
vector v = $<vector>direction;
...
};
These substitutions are now possible in all code blocks. Blocks with
access to the dictionary (e.g., #codeRead) will do a lookup which will
not require re-compilation if the value is changed. Blocks without
access to the dictionary will have the value directly substituted, and
will require recompilation when the value is changed.
The patch-specific mapper interfaces, fvPatchFieldMapper and
pointPatchFieldMapper, have been removed as they did not do anything.
Patch mapping constructors and functions now take a basic fieldMapper
reference.
An fvPatchFieldMapper.H header has been provided to aid backwards
compatability so that existing custom boundary conditions continue to
compile.
The interface for fvModels has been modified to improve its application
to "proxy" equations. That is, equations that are not straightforward
statements of conservation laws in OpenFOAM's usual convention.
A standard conservation law typically takes the following form:
fvMatrix<scalar> psiEqn
(
fvm::ddt(alpha, rho, psi)
+ <fluxes>
==
<sources>
);
A proxy equation, on the other hand, may be a derivation or
rearrangement of a law like this, and may be linearised in terms of a
different variable.
The pressure equation is the most common example of a proxy equation. It
represents a statement of the conservation of volume or mass, but it is
a rearrangement of the original continuity equation, and it has been
linearised in terms of a different variable; the pressure. Another
example is that in the pre-predictor of a VoF solver the
phase-continuity equation is constructed, but it is linearised in terms
of volume fraction rather than density.
In these situations, fvModels sources are now applied by calling:
fvModels().sourceProxy(<conserved-fields ...>, <equation-field>)
Where <conserved-fields ...> are (alpha, rho, psi), (rho, psi), just
(psi), or are omitted entirely (for volume continuity), and the
<equation-field> is the field associated with the proxy equation. This
produces a source term identical in value to the following call:
fvModels().source(<conserved-fields ...>)
It is only the linearisation in terms of <equation-field> that differs
between these two calls.
This change permits much greater flexibility in the handling of mass and
volume sources than the previous name-based system did. All the relevant
fields are available, dimensions can be used in the logic to determine
what sources are being constructed, and sources relating to a given
conservation law all share the same function.
This commit adds the functionality for injection-type sources in the
compressibleVoF solver. A following commit will add a volume source
model for use in incompressible solvers.
The old fluid-specific rhoThermo has been split into a non-fluid
specific part which is still called rhoThermo, and a fluid-specific part
called rhoFluidThermo. The rhoThermo interface has been added to the
solidThermo model. This permits models and solvers that access the
density to operate on both solid and fluid thermophysical models.
The he*Thermo classes have been renamed to match their corresponding
basic thermo classes. E.g., rhoThermo now corresponds to RhoThermo,
rather than heRhoThermo.
Mixture classes (e.g., pureMixtrure, coefficientMulticomponentMixture),
now have no fvMesh or volScalarField dependence. They operate on
primitive values only. All the fvMesh-dependent functionality has been
moved into the base thermodynamic classes. The 'composition()' access
function has been removed from multi-component thermo models. Functions
that were once provided by composition base classes such as
basicSpecieMixture and basicCombustionMixture are now implemented
directly in the relevant multi-component thermo base class.
Dictionary entries constructed with #calc and #codeStream can now
conveniently access and use typed variables. This means calculations
involving vectors and tensors and list and field types are now possible.
To access a variable and construct it as a given type within a #calc
or #codeStream entry, put the type immediately after the $ symbol inside
angled brackets <>. So, $<vector>var or $<vector>{var} substitutes a
variable named var as a vector.
Examples:
- Reflect a point in a plane defined by a normal
p (1 2 3);
n (1 1 0);
pStar #calc "$<vector>p - (2*sqr($<vector>n)/magSqr($<vector>n)&$<vector>p)";
- Rotate a list of points around an axis by a given angle
points ((3 0 0) (2 1 1) (1 2 2) (0 3 3));
rotation
{
axis (0 1 1);
angle 45;
}
#codeStream
{
codeInclude
#{
#include "pointField.H"
#include "transform.H"
#};
code
#{
const pointField points($<List<point>>points);
const vector axis = $<vector>!rotation/axis;
const scalar angle = degToRad($!rotation/angle);
os << "pointsRotated" << nl << (Ra(axis, angle) & points)() << ";";
#};
};
- Compute the centre and trianglation of a polygon
polygon ((0 0 0) (1 0 0) (2 1 0) (0 2 0) (-1 1 0));
#codeStream
{
codeInclude
#{
#include "polygonTriangulate.H"
#};
code
#{
const List<point> polygon($<List<point>>polygon);
writeEntry(os, "polygonCentre", face::centre(polygon));
polygonTriangulate triEngine;
triEngine.triangulate(polygon);
os << "polygonTris" << ' ' << triEngine.triPoints() << ";";
#};
};
- Generate a single block blockMeshDict for use with snappyHexMesh with no redundant information
min (-2.5 -1.2 -3.0); // Minimum coordinates of the block
max (2.5 1.2 3.0); // Maximum coordinates of the block
nCellsByL 33.3333; // Number of cells per unit length
// Calculate the number of cells in each block direction
nCells #calc "Vector<label>($nCellsByL*($<vector>max - $<vector>min) + vector::one/2)";
// Generate the vertices using a boundBox
vertices #codeStream
{
codeInclude
#{
#include "boundBox.H"
#};
code
#{
os << boundBox($<vector>min, $<vector>max).points();
#};
};
blocks
(
hex (0 1 2 3 4 5 6 7) $nCells simpleGrading (1 1 1)
);
defaultPatch
{
type patch;
}
boundary
();
Specific names have been given for expand functions. Unused functions
have been removed, and functions only used locally have been removed
from the namespace. Documentation has been corrected. Default and
alternative value handling has been removed from code template
expansion.
This avoids potential hidden run-time errors caused by solvers running with
boundary conditions which are not fully specified. Note that "null-constructor"
here means the constructor from patch and internal field only, no data is
provided.
Constraint and simple BCs such as 'calculated', 'zeroGradient' and others which
do not require user input to fully specify their operation remain on the
null-constructor table for the construction of fields with for example all
'calculated' or all 'zeroGradient' BCs.
Following this improvement the null-constructors have been removed from all
pointPatchFields not added to the null-constructor table thus reducing the
amount of code and maintenance overhead and making easier and more obvious to
write new pointPatchField types.
The codedFunctionObjectTemplate is based on regionFunctionObject requiring
fvMesh.H and most manipulate volFields so it makes sense for volFields.H to be
included by default.
MRF (multiple reference frames) can now be used to simulate SRF (single
reference frame) cases by defining the MRF zone to include all the cells is the
mesh and applying appropriate boundary conditions. The huge advantage of this
is that MRF can easily be added to any solver by the addition of forcing terms
in the momentum equation and absolute velocity to relative flux conversions in
the formulation of the pressure equation rather than having to reformulate the
momentum and pressure system based on the relative velocity as in traditional
SRF. Also most of the OpenFOAM solver applications and all the solver modules
already support MRF.
To enable this generalisation of MRF the transformations necessary on the
velocity boundary conditions in the MRF zone can no longer be handled by the
MRFZone class itself but special adapted fvPatchFields are required. Although
this adds to the case setup it provides much greater flexibility and now complex
inlet/outlet conditions can be applied within the MRF zone, necessary for some
SRF case and which was not possible in the original MRF implementation. Now for
walls rotating within the MRF zone the new 'MRFnoSlip' velocity boundary
conditions must be applied, e.g. in the
tutorials/modules/incompressibleFluid/mixerVessel2DMRF/constant/MRFProperties
case:
boundaryField
{
rotor
{
type MRFnoSlip;
}
stator
{
type noSlip;
}
front
{
type empty;
}
back
{
type empty;
}
}
similarly for SRF cases, e.g. in the
tutorials/modules/incompressibleFluid/mixerSRF case:
boundaryField
{
inlet
{
type fixedValue;
value uniform (0 0 -10);
}
outlet
{
type pressureInletOutletVelocity;
value $internalField;
}
rotor
{
type MRFnoSlip;
}
outerWall
{
type noSlip;
}
cyclic_half0
{
type cyclic;
}
cyclic_half1
{
type cyclic;
}
}
For SRF case all the cells should be selected in the MRFproperties dictionary
which is achieved by simply setting the optional 'selectionMode' entry to all,
e.g.:
SRF
{
selectionMode all;
origin (0 0 0);
axis (0 0 1);
rpm 1000;
}
In the above the rotational speed is set in RPM rather than rad/s simply by
setting the 'rpm' entry rather than 'omega'.
The tutorials/modules/incompressibleFluid/rotor2DSRF case is more complex and
demonstrates a transient SRF simulation of a rotor requiring the free-stream
velocity to rotate around the apparently stationary rotor which is achieved
using the new 'MRFFreestreamVelocity' velocity boundary condition. The
equivalent simulation can be achieved by simply rotating the entire mesh and
keeping the free-stream flow stationary and this is demonstrated in the
tutorials/modules/incompressibleFluid/rotor2DRotating case for comparison.
The special SRFSimpleFoam and SRFPimpleFoam solvers are now redundant and have
been replaced by redirection scripts providing details of the case migration
process.
Full backward-compatibility is provided which support for both multiComponentMixture and
multiComponentPhaseModel provided but all tutorials have been updated.
Now that the reaction system, chemistry and combustion models are completely
separate from the multicomponent mixture thermophysical properties package that
supports them it is inconsistent that thermo is named reactionThermo and the
name multicomponentThermo better describes the purpose and functionality.
This new mapping structure is designed to support run-time mesh-to-mesh mapping
to allow arbitrary changes to the mesh structure, for example during extreme
motion requiring significant topology change including region disconnection etc.
The polyTopoChangeMap is the map specifically relating to polyMesh topological
changes generated by polyTopoChange and used to update and map mesh related
types and fields following the topo-change.
This is a map data structure rather than a class or function which performs the
mapping operation so polyMeshDistributionMap is more logical and comprehensible
than mapDistributePolyMesh.
With the changes to chemistryModel to evaluate and integrate reaction rates
mass-fraction based rather than mole-fraction based ISAT is now independent of
the thermodynamics and with some restructuring of chemistryModel and the
addition of the non-templated base-class odeChemistryModel is has been possible
to un-template chemistryTabulationMethods and ISAT in particular. This
simplifies the ISAT code and hence maintenance as well as reducing the
compilation time of chemistryModel on the various thermo packages.
Description
Transport package using the Andrade function for the natural logarithm of
dynamic viscosity and thermal conductivity of liquids:
\verbatim
log(mu) = muCoeffs[0] + muCoeffs[1]*T + muCoeffs[2]*sqr(T)
+ muCoeffs_[3]/(muCoeffs_[4] + T)
log(kappa) = kappaCoeffs[0] + kappaCoeffs[1]*T + kappaCoeffs[2]*sqr(T)
+ kappaCoeffs_[3]/(kappaCoeffs_[4] + T)
);
\endverbatim
References:
\verbatim
Andrade, E. D. C. (1934).
XLI. A theory of the viscosity of liquids.—Part I.
The London, Edinburgh, and Dublin Philosophical Magazine
and Journal of Science, 17(112), 497-511.
Andrade, E. D. C. (1934).
LVIII. A theory of the viscosity of liquids.—Part II.
The London, Edinburgh, and Dublin Philosophical Magazine
and Journal of Science, 17(113), 698-732.
\endverbatim
Usage
\table
Property | Description
muCoeffs | Dynamic viscosity polynomial coefficients
kappaCoeffs | Thermal conductivity polynomial coefficients
\endtable
Example of the specification of the transport properties for water@200bar:
\verbatim
transport
{
muCoeffs (-25.8542 0.031256 -2.2e-05 3289.918 -11.4784);
kappaCoeffs (-2.56543 0.008794 -9.8e-06 100.368 0);
}
\endverbatim
With this change each functionObject provides the list of fields required so
that the postProcess utility can pre-load them before executing the list of
functionObjects. This provides a more convenient interface than using the
-field or -fields command-line options to postProcess which are now redundant.
Description
Transport properties package using non-uniformly-spaced tabulated data for
thermal conductivity vs temperature.
Usage
\table
Property | Description
kappa | Thermal conductivity vs temperature table
\endtable
Example of the specification of the transport properties:
\verbatim
transport
{
kappa
{
values
(
(200 380)
(350 400)
(400 450)
);
}
}
\endverbatim
This required standardisation of the mapping between the class and selection
names of the solid transport models:
constIso -> constIsoSolid
exponential -> exponentialSolid
polynomial -> polynomialSolid
To simplify maintenance and further development of chemistry solution the
standardChemistryModel and TDACChemistryModel have been merged into the single
chemistryModel class. Now the TDAC mechanism reduction and tabulation
components can be individually selected or set to "none" or the corresponding
entries in the chemistryProperties dictionary omitted to switch them off thus
reproducing the behaviour of the standardChemistryModel.
For example the following chemistryProperties includes TDAC:
#includeEtc "caseDicts/solvers/chemistry/TDAC/chemistryProperties.cfg"
chemistryType
{
solver ode;
}
chemistry on;
initialChemicalTimeStep 1e-7;
odeCoeffs
{
solver seulex;
absTol 1e-8;
relTol 1e-1;
}
reduction
{
tolerance 1e-4;
}
tabulation
{
tolerance 3e-3;
}
#include "reactionsGRI"
and to run without TDAC the following is sufficient:
chemistryType
{
solver ode;
}
chemistry on;
initialChemicalTimeStep 1e-7;
odeCoeffs
{
solver seulex;
absTol 1e-8;
relTol 1e-1;
}
#include "reactionsGRI"
or the "reduction" and "tabulation" entries can be disabled explicitly:
#includeEtc "caseDicts/solvers/chemistry/TDAC/chemistryProperties.cfg"
chemistryType
{
solver ode;
}
chemistry on;
initialChemicalTimeStep 1e-7;
odeCoeffs
{
solver seulex;
absTol 1e-8;
relTol 1e-1;
}
reduction
{
method none;
tolerance 1e-4;
}
tabulation
{
method none;
tolerance 3e-3;
}
#include "reactionsGRI"
to provide a single consistent code and user interface to the specification of
physical properties in both single-phase and multi-phase solvers. This redesign
simplifies usage and reduces code duplication in run-time selectable solver
options such as 'functionObjects' and 'fvModels'.
* physicalProperties
Single abstract base-class for all fluid and solid physical property classes.
Physical properties for a single fluid or solid within a region are now read
from the 'constant/<region>/physicalProperties' dictionary.
Physical properties for a phase fluid or solid within a region are now read
from the 'constant/<region>/physicalProperties.<phase>' dictionary.
This replaces the previous inconsistent naming convention of
'transportProperties' for incompressible solvers and
'thermophysicalProperties' for compressible solvers.
Backward-compatibility is provided by the solvers reading
'thermophysicalProperties' or 'transportProperties' if the
'physicalProperties' dictionary does not exist.
* phaseProperties
All multi-phase solvers (VoF and Euler-Euler) now read the list of phases and
interfacial models and coefficients from the
'constant/<region>/phaseProperties' dictionary.
Backward-compatibility is provided by the solvers reading
'thermophysicalProperties' or 'transportProperties' if the 'phaseProperties'
dictionary does not exist. For incompressible VoF solvers the
'transportProperties' is automatically upgraded to 'phaseProperties' and the
two 'physicalProperties.<phase>' dictionary for the phase properties.
* viscosity
Abstract base-class (interface) for all fluids.
Having a single interface for the viscosity of all types of fluids facilitated
a substantial simplification of the 'momentumTransport' library, avoiding the
need for a layer of templating and providing total consistency between
incompressible/compressible and single-phase/multi-phase laminar, RAS and LES
momentum transport models. This allows the generalised Newtonian viscosity
models to be used in the same form within laminar as well as RAS and LES
momentum transport closures in any solver. Strain-rate dependent viscosity
modelling is particularly useful with low-Reynolds number turbulence closures
for non-Newtonian fluids where the effect of bulk shear near the walls on the
viscosity is a dominant effect. Within this framework it would also be
possible to implement generalised Newtonian models dependent on turbulent as
well as mean strain-rate if suitable model formulations are available.
* visosityModel
Run-time selectable Newtonian viscosity model for incompressible fluids
providing the 'viscosity' interface for 'momentumTransport' models.
Currently a 'constant' Newtonian viscosity model is provided but the structure
supports more complex functions of time, space and fields registered to the
region database.
Strain-rate dependent non-Newtonian viscosity models have been removed from
this level and handled in a more general way within the 'momentumTransport'
library, see section 'viscosity' above.
The 'constant' viscosity model is selected in the 'physicalProperties'
dictionary by
viscosityModel constant;
which is equivalent to the previous entry in the 'transportProperties'
dictionary
transportModel Newtonian;
but backward-compatibility is provided for both the keyword and model
type.
* thermophysicalModels
To avoid propagating the unnecessary constructors from 'dictionary' into the
new 'physicalProperties' abstract base-class this entire structure has been
removed from the 'thermophysicalModels' library. The only use for this
constructor was in 'thermalBaffle' which now reads the 'physicalProperties'
dictionary from the baffle region directory which is far simpler and more
consistent and significantly reduces the amount of constructor code in the
'thermophysicalModels' library.
* compressibleInterFoam
The creation of the 'viscosity' interface for the 'momentumTransport' models
allows the complex 'twoPhaseMixtureThermo' derived from 'rhoThermo' to be
replaced with the much simpler 'compressibleTwoPhaseMixture' derived from the
'viscosity' interface, avoiding the myriad of unused thermodynamic functions
required by 'rhoThermo' to be defined for the mixture.
Same for 'compressibleMultiphaseMixture' in 'compressibleMultiphaseInterFoam'.
This is a significant improvement in code and input consistency, simplifying
maintenance and further development as well as enhancing usability.
Henry G. Weller
CFD Direct Ltd.
The FOAM file format has not changed from version 2.0 in many years and so there
is no longer a need for the 'version' entry in the FoamFile header to be
required and to reduce unnecessary clutter it is now optional, defaulting to the
current file format 2.0.
