Simulating the mixing of two miscible liquids is possible my considering
them as different species of a multicomponent fluid. This approach also
supports an arbitrary number of liquids. The twoLiquidMixingFoam solver
has therefore been removed and its tutorials converted to use the
multicomponentFluid solver module.
Bubble waiting time ratio has been made a user adjustable parameter, and
the names of the fields reported by the wallBoilingProperties function
have been rationalised.
This tutorial's purpose was to demonstrate rebound off an internal
cyclic patch, and thereby "filter" the particles out of the downstream
sections of the geometry. The case does not correctly do this. The patch
interaction handling is incomplete and does not support overriding
cyclic boundary conditions in this way. This tutorial has therefore been
removed pending funding to improve the patch interaction modelling.
Resolves bug report https://bugs.openfoam.org/view.php?id=3923
Now cases with mesh refinement/unrefinement can be run with the 2nd-order
backward time scheme. However this is for static meshes only, 2nd-order in time
with topology change AND mesh-motion is not currently supported.
These tutorials now make make use of the phaseTurbulenceStabilisation
fvModel and the wallBoilingProperties functionObject.
Patch contributed by Juho Peltola, VTT.
executed with foamRun for single region simulations of foamMultiRun for
multi-region simulations. Replaces multiphaseEulerFoam and all the
corresponding tutorials have been updated and moved to
tutorials/modules/multiphaseEuler.
Class
Foam::solvers::multiphaseEuler
Description
Solver module for a system of any number of compressible fluid phases with a
common pressure, but otherwise separate properties. The type of phase model
is run time selectable and can optionally represent multiple species and
in-phase reactions. The phase system is also run time selectable and can
optionally represent different types of momentum, heat and mass transfer.
Uses the flexible PIMPLE (PISO-SIMPLE) solution for time-resolved and
pseudo-transient and steady simulations.
Optional fvModels and fvConstraints are provided to enhance the simulation
in many ways including adding various sources, Lagrangian
particles, surface film etc. and constraining or limiting the solution.
SourceFiles
multiphaseEuler.C
See also
Foam::solvers::compressibleVoF
Foam::solvers::fluidSolver
Foam::solvers::incompressibleFluid
No advantage was found in the specific snappyHexMesh settings previously
specified for this case. This case now uses settings from the standard
snappyHexMesh.cfg file.
The rotating region has also been modified to align better with the
original block mesh. For sliding interface problems this is important in
order to reliably get good conformance to the cylinder edges.
After direct and regular expression matching the scheme name is now filtered to
remove and group/phase extensions in the name and matched again with the schemes
dictionary.
This significantly simplifies the specification of schemes in multiphase
simulations, instead of the rather messy regular expressions the new method
allows schemes to be specified without the group/phase name extension and the
scheme is then used for all groups/phases. For example in the bubbleColumn
tutorials the schemes can now be specified thus:
divSchemes
{
default none;
div(phi,alpha) Gauss vanLeer;
div(phir,alpha,alpha) Gauss vanLeer;
div(alphaRhoPhi,U) Gauss limitedLinearV 1;
div(phi,U) Gauss limitedLinearV 1;
div(alphaRhoPhi,e) Gauss limitedLinear 1;
div(alphaRhoPhi,K) Gauss limitedLinear 1;
div(alphaRhoPhi,(p|rho)) Gauss limitedLinear 1;
div((((alpha*rho)*nuEff)*dev2(T(grad(U))))) Gauss linear;
}
rather than using complex regular expressions as done previously:
divSchemes
{
default none;
div(phi,alpha.air) Gauss vanLeer;
div(phi,alpha.water) Gauss vanLeer;
div(phir,alpha.water,alpha.air) Gauss vanLeer;
div(phir,alpha.air,alpha.water) Gauss vanLeer;
"div\(alphaRhoPhi.*,U.*\)" Gauss limitedLinearV 1;
"div\(phi.*,U.*\)" Gauss limitedLinearV 1;
"div\(alphaRhoPhi.*,(h|e).*\)" Gauss limitedLinear 1;
"div\(alphaRhoPhi.*,K.*\)" Gauss limitedLinear 1;
"div\(alphaRhoPhi.*,\(p\|rho.*\)\)" Gauss limitedLinear 1;
"div\(alphaRhoPhi.*,\(p\|rho.*\)\)" Gauss limitedLinear 1;
"div\(\(\(\(alpha.*\*rho.*\)*nuEff.*\)\*dev2\(T\(grad\(U.*\)\)\)\)\)" Gauss linear;
}
The thermodynamic density field is now named "rho" by default and only renamed
"thermo:rho" by solvers that create and maintain a separate continuity density
field which is named "rho". This change significantly simplifies and
standardises the specification of schemes and boundary conditions requiring
density as it is now always named "rho" or "rho.<phase>" unless under some very
unusual circumstances the thermodynamic rather than continuity density is
required for a solver maintaining both.
The advantage of this change is particularly noticeable for multiphase
simulations in which each phase has its own density now named "rho.<phase>"
rather than "thermo:rho.<phase>" as separate phase continuity density fields are
not required so for multiphaseEulerFoam the scheme specification:
"div\(alphaRhoPhi.*,\(p\|thermo:rho.*\)\)" Gauss limitedLinear 1;
is now written:
"div\(alphaRhoPhi.*,\(p\|rho.*\)\)" Gauss limitedLinear 1;
The basic thermophysical properties are now considered fundamental and complex
models like kineticTheoryModel using these names for some other purpose must
disambiguate using typedName to prepend the model name to the field name.
This change standardises, rationalises and simplifies the specification of
fvSchemes and boundary conditions.
thermo:rho will also be renamed rho in a subsequent commit to complete this
rationalisation.
Description
Uniform or non-uniform constant solid thermodynamic properties
Each physical property can specified as either \c uniform in which case the
value entry is read or \c file in which case the field file in read
from the constant directory.
Usage
Example of uniform constant solid properties specification:
\verbatim
thermoType constSolidThermo;
rho
{
type uniform;
value 8940;
}
Cv
{
type uniform;
value 385;
}
kappa
{
type uniform;
value 380;
}
\endverbatim
Example of non-uniform constant solid properties specification:
\verbatim
thermoType constSolidThermo;
rho
{
type file;
}
Cv
{
type file;
}
kappa
{
type file;
}
\endverbatim
where each of the field files are read from the constant directory.
the new fluidThermophysicalTransportModel and solidThermophysicalTransportModel
are derived from thermophysicalTransportModel providing a consistent and unified
interface for heat transport within and between regions. Coupled and external
heat-transfer boundary conditions can now be written independent of the
thermophysical properties or transport modelling of the regions providing
greater flexibility, simpler code and reduces the maintenance overhead.
The previous fluidThermophysicalTransportModel typedef has been renamed
fluidThermoThermophysicalTransportModel as it is instantiated on fluidThermo,
freeing the name fluidThermophysicalTransportModel for the new base-class.
The surfaceFilm fvModel has been renamed surfaceFilms, and can now have
a number of independent film models specified.
For example, the hotBoxes tutorial could be modified to have separate
film regions for the boxes and for the floor. In which case, the names
of the separate films would need specifying as shown below.
surfaceFilms
{
type surfaceFilms;
surfaceFilms (boxesFilm floorFilm); // <-- new entry
libs ("libsurfaceFilmModels.so");
}
The old fvModel name, surfaceFilm, has been maintained for backwards
compatibility.
The Lagrangian surface film model now also requires the coupled
surfaceFilms to be specified when there is not just a single
default-named film. For example, in constant/cloudProperties:
subModels
{
surfaceFilmModel thermoSurfaceFilm;
thermoSurfaceFilmCoeffs
{
surfaceFilms (boxesFilm floorFilm); // <-- new entry
interactionType splashBai;
deltaWet 0.0005;
Adry 2630;
Awet 1320;
Cf 0.6;
}
...
}
to handle isotropic and anisotropic is a consistent, general and extensible
manner, replacing the horrible hacks which were in solidThermo.
This is entirely consistent with thermophysicalTransportModel for fluids and
provides the q() and divq() for the solid energy conservation equations. The
transport model and properties are specified in the optional
thermophysicalTransport dictionary, the default model being isotropic if this
dictionary file is not present, thus providing complete backward-compatibility
for the common isotropic cases.
Anisotropic thermal conductivity is now handled in a much more general manner by
the anisotropic model:
Class
Foam::solidThermophysicalTransportModels::anisotropic
Description
Solid thermophysical transport model for anisotropic thermal conductivity
The anisotropic thermal conductivity field is evaluated from the solid
material anisotropic kappa specified in the physicalProperties dictionary
transformed into the global coordinate system using default
coordinate system and optionally additional coordinate systems specified
per-zone in the thermophysicalProperties dictionary.
Usage
Example of the anisotropic thermal conductivity specification in
thermophysicalProperties with two zone-based coordinate systems in
addition to the default:
\verbatim
model anisotropic;
// Default coordinate system
coordinateSystem
{
type cartesian;
origin (0 0 0);
coordinateRotation
{
type cylindrical;
e3 (1 0 0);
}
}
// Optional zone coordinate systems
zones
{
coil1
{
type cartesian;
origin (0.1 0.2 0.7);
coordinateRotation
{
type cylindrical;
e3 (0.5 0.866 0);
}
}
coil2
{
type cartesian;
origin (0.4 0.5 1);
coordinateRotation
{
type cylindrical;
e3 (0.866 0.5 0);
}
}
}
\endverbatim
This development required substantial rationalisation of solidThermo,
coordinateSystems and updates to the solid solver module, solidDisplacementFoam,
the wallHeatFlux functionObject, thermalBaffle and all coupled thermal boundary
conditions.
to enable writing of the isotropicDamping:forceCoeff isotropicDamping:scale
waveForcing:forceCoeff waveForcing:scale diagnostic fields to check the damping
and forcing distributions.
Lagrangian is now compatible with the meshToMesh topology changer. If a
cloud is being simulated and this topology changer is active, then the
cloud data will be automatically mapped between the specified sequence
of meshes in the same way as the finite volume data. This works both for
serial and parallel simulations.
In addition, mapFieldsPar now also supports mapping of Lagrangian data
when run in parallel.
Renamed classes:
turbulentTemperatureCoupledBaffleMixedFvPatchScalarField ->
coupledTemperatureFvPatchScalarField
externalWallHeatFluxTemperatureFvPatchScalarField ->
externalTemperatureFvPatchScalarField
Radiation heat-flux support in turbulentTemperatureRadCoupledMixed transferred
to coupledTemperatureFvPatchScalarField and turbulentTemperatureRadCoupledMixed removed.
Renamed boundary condition type names in T field files:
compressible::turbulentTemperatureCoupledBaffleMixed -> coupledTemperature
compressible::turbulentTemperatureRadCoupledMixed -> coupledTemperature
compressible::externalWallHeatFluxTemperature -> externalTemperature
Backward-compatibility is provided for all three of the above BC specifications
so existing cases will run as before but we recommend migrating to the new
simpler names.
so that it can now be used with either the isothermalFluid or fluid solver
modules, thus supporting non-uniform fluid properties, compressibility and
thermal effect. This development makes the special potentialFreeSurfaceFoam
solver redundant as both the isothermalFluid and fluid solver modules are more
general and has been removed and replaced with a user redirection script.
The tutorials/multiphase/potentialFreeSurfaceFoam cases have been updated to run
with the isothermalFluid solver module:
tutorials/multiphase/potentialFreeSurfaceFoam/oscillatingBox
tutorials/multiphase/potentialFreeSurfaceFoam/movingOscillatingBox
which demonstrate how to upgrade potentialFreeSurfaceFoam cases to
isothermalFluid.
and demonstrates the wave being generated in a region adjacent to the outlet and
propagating upstream towards the inlet where it is damped by a damping region
and mesh expansion.
to avoid further confusion concerning the origin of the thermo and transport
data which is not that supplied with the GRI mechanism as the these simple test
cases is to demonstrate the integration of a complex mechanism with or without
TDAC and ISAT, not complex transport modelling.
The proposed change does not change the mixing rules and the default coefficient mixing approach does not
provide mixed properties consistent with the GRI specification. The purpose of these simple test cases
is to demonstrate the integration of a complex mechanism with or without TDAC and ISAT, not complex transport modelling.
A new tutorial is required to demonstrate the GRI 3.0 mechanism with complex transport properties.
This reverts commit 53f3bc6fdd.
With waveForcing waves can be generated with a domain by applying forcing to
both the phase-fraction and velocity fields rather than requiring that the waves
are introduced at an inlet. This provides much greater flexibility as waves can
be generated in any direction relative to the mean flow, obliquely or even
against the flow. isotropicDamping or verticalDamping can be used in
conjunction with waveForcing to damp the waves before they reach an outlet,
alternatively waveForcing can be used in regions surrounding a hull for example
to maintain far-field waves everywhere.
The tutorials/multiphase/interFoam/laminar/forcedWave tutorial case is provided
to demonstrate the waveForcing fvModel as an alternative to the wave inlet
boundary conditions used in the tutorials/multiphase/interFoam/laminar/wave
case.
Class
Foam::fv::waveForcing
Description
This fvModel applies forcing to the liquid phase-fraction field and all
components of the vector field to relax the fields towards those
calculated from the current wave distribution.
The forcing force coefficient \f$\lambda\f$ should be set based on the
desired level of forcing and the residence time the waves through the
forcing zone. For example, if waves moving at 2 [m/s] are travelling
through a forcing zone 8 [m] in length, then the residence time is 4 [s]. If
it is deemed necessary to force for 5 time-scales, then \f$\lambda\f$ should
be set to equal 5/(4 [s]) = 1.2 [1/s].
Usage
Example usage:
\verbatim
waveForcing1
{
type waveForcing;
libs ("libwaves.so");
liquidPhase water;
// Define the line along which to apply the graduation
origin (600 0 0);
direction (-1 0 0);
// // Or, define multiple lines
// origins ((600 0 0) (600 -300 0) (600 300 0));
// directions ((-1 0 0) (0 1 0) (0 -1 0));
scale
{
type halfCosineRamp;
start 0;
duration 300;
}
lambda 0.5; // Forcing coefficient
}
\endverbatim
Replacing the specific twoPhaseChangeModel with a consistent and general fvModel
interface will support not just cavitation using the new compressible
VoFCavitation fvModel but also other phase-change and interface manipulation
models in the future and is easier to use for case-specific and other user
customisation.
Class
Foam::fv::compressible::VoFCavitation
Description
Cavitation fvModel
Usage
Example usage:
\verbatim
VoFCavitation
{
type VoFCavitation;
libs ("libcompressibleVoFCavitation.so");
model SchnerrSauer;
KunzCoeffs
{
pSat 2300; // Saturation pressure
UInf 20.0;
tInf 0.005; // L = 0.1 m
Cc 1000;
Cv 1000;
}
MerkleCoeffs
{
pSat 2300; // Saturation pressure
UInf 20.0;
tInf 0.005; // L = 0.1 m
Cc 80;
Cv 1e-03;
}
SchnerrSauerCoeffs
{
pSat 2300; // Saturation pressure
n 1.6e+13;
dNuc 2.0e-06;
Cc 1;
Cv 1;
}
}
\endverbatim
The cavitating ballValve tutorial has been updated to use the new VoFCavitation
fvModel.
Replacing the specific twoPhaseChangeModel with a consistent and general fvModel
interface will support not just cavitation using the new VoFCavitation fvModel
but also other phase-change and interface manipulation models in the future and
is easier to use for case-specific and other user customisation.
The clouds fvModel and all the clouds it creates now contain a full set
of mesh change hooks. Some of these ultimately result in
"NotImplemented" errors, but this is an area under active development
and support may be added in the near future.
In addition, the list of cloud names is now specified from within the
fvModel, using a "clouds" entry. If this entry is omitted then a single
cloud named "cloud" is assumed as before. An example fvModel
specification for multiple clouds might be as follows:
clouds
{
type clouds;
libs ("liblagrangianParcel.so" "liblagrangianParcelTurbulence.so");
clouds (coalCloud limestoneCloud); // <-- New entry. Replaces
// the constant/clouds
// file.
}
Lagrangian solvers that construct clouds explicitly now do so via a new
"parcelClouds" mesh object. This ensures that they, too, are correctly
modified as a result of mesh changes.
Neither mechanism now permits no clouds. If there is not a "clouds"
entry (clouds fvModel), or a constant/clouds file (lagrangian solvers),
and there is not a constant/cloudProperties file for the default cloud,
then an error will be generated. Previously the code executed the solver
with no clouds. Intentional usage of the fvModel or lagrangian solvers
without clouds is considered highly unlikely.
The mappedPatchBase has been separated into a type which maps from
another patch (still called mappedPatchBase) and one that maps from
internal cell values (mappedInternalPatchBase). This prevents the user
needing to specify settings for mapping procedures that are not being
used, and potentially don't even make sense given the context in which
they are being applied. It also removes a lot of fragile logic and error
states in the mapping engine and its derivatives regarding the mode of
operation. Mapping from any face in the boundary is no longer supported.
Most region-coupling mapping patches are generated automatically by
utilities like splitMeshRegions and extrudeToRegionMesh. Cases which
create region-coupling mapped patches in this way will likely require no
modification.
Explicitly user-specified mapping will need modifying, however. For
example, where an inlet boundary is mapped to a downstream position in
order to evolve a developed profile. Or if a multi-region simulation is
constructed manually, without using one of the region-generating
utilities.
The available mapped patch types are now as follows:
- mapped: Maps values from one patch to another. Typically used for
inlets and outlets; to map values from an outlet patch to an inlet
patch in order to evolve a developed inlet profile, or to permit
flow between regions. Example specification in blockMesh:
inlet
{
type mapped;
neighbourRegion region0; // Optional. Defaults to the same
// region as the patch.
neighbourPatch outlet;
faces ( ... );
}
Note that any transformation between the patches is now determined
automatically. Alternatively, it can be explicitly specified using
the same syntax as for cyclic patches. The "offset" and "distance"
keywords are no longer used.
- mappedWall: As mapped, but treated as a wall for the purposes of
modelling (wall distance). No transformation. Typically used for
thermally coupling different regions. Usually created automatically
by meshing utilities. Example:
fluid_to_solid
{
type mappedWall;
neighbourRegion solid;
neighbourPatch solid_to_fluid;
method intersection; // The patchToPatch method. See
// below.
faces ( ... );
}
- mappedExtrudedWall: As mapped wall, but with corrections to account
for the thickness of an extruded mesh. Used for region coupling
involving film and thermal baffle models. Almost always generated
automatically by extrudeToRegionMesh (so no example given).
- mappedInternal: Map values from internal cells to a patch. Typically
used for inlets; to map values from internal cells to the inlet in
order to evolve a developed inlet profile. Example:
inlet
{
type mappedInternal;
distance 0.05; // Normal distance from the patch
// from which to map cell values
//offset (0.05 0 0); // Offset from the patch from
// which to map cell values
faces ( ... );
}
Note that an "offsetMode" entry is no longer necessary. The mode
will be inferred from the presence of the distance or offset
entries. If both are provided, then offsetMode will also be required
to choose which setting applies.
The mapped, mappedWall and mappedExtrudedWall patches now permit
specification of a "method". This selects a patchToPatch object and
therefore determines how values are transferred or interpolated between
the patches. Valid options are:
- nearest: Copy the value from the nearest face in the neighbouring
patch.
- matching: As nearest, but with checking to make sure that the
mapping is one-to-one. This is appropriate for patches that are
identically meshed.
- inverseDistance: Inverse distance weighting from a small stencil of
nearby faces in the neighbouring patch.
- intersection: Weighting based on the overlapping areas with faces in
the neighbouring patch. Equivalent to the previous AMI-based mapping
mode.
If a method is not specfied, then the pre-existing approach will apply.
This should be equivalent to the "nearest" method (though in most such
cases, "matching" is probably more appropriate). This fallback may be
removed in the future once the patchToPatch methods have been proven
robust.
The important mapped boundary conditions are now as follows:
- mappedValue: Maps values from one patch to another, and optionally
modify the mapped values to recover a specified average. Example:
inlet
{
type mappedValue;
field U; // Optional. Defaults to the same
// as this field.
average (10 0 0); // The presence of this entry now
// enables setting of the average,
// so "setAverage" is not needed
value uniform 0.1;
}
- mappedInternalValue: Map values from cells to a patch, and
optionally specify the average as in mappedValue. Example:
inlet
{
type mappedValue;
field k; // Optional. Defaults to the same
// as this field.
interpolationScheme cell;
value uniform 0.1;
}
- mappedFlowRateVelocity: Maps the flow rate from one patch to
another, and use this to set a patch-normal velocity. Example:
inlet
{
type mappedFlowRate;
value uniform (0 0 0);
}
Of these, mappedValue and mappedInternalValue can override the
underlying mapped patch's settings by additionally specifying mapping
information (i.e., the neighbourPatch, offset, etc... settings usually
supplied for the patch). This also means these boundary condtions can be
applied to non-mapped patches. This functionality used to be provided
with a separate "mappedField" boundary condition, which has been removed
as it is no longer necessary.
Other mapped boundary conditions are either extremely niche (e.g.,
mappedVelocityFlux), are always automatically generated (e.g.,
mappedValueAndPatchInternalValue), or their usage has not changed (e.g.,
compressible::turbulentTemperatureCoupledBaffleMixed and
compressible::turbulentTemperatureRadCoupledMixed). Use foamInfo to
obtain further details about these conditions.
executed with foamRun for single region simulations of foamMultiRun for
multi-region simulations. Replaces compressibleInterFoam and all the
corresponding tutorials have been updated and moved to
tutorials/modules/compressibleVoF.
Class
Foam::solvers::compressibleVoF
Description
Solver module for for 2 compressible, non-isothermal immiscible fluids
using a VOF (volume of fluid) phase-fraction based interface capturing
approach, with optional mesh motion and mesh topology changes including
adaptive re-meshing.
The momentum and other fluid properties are of the "mixture" and a single
momentum equation is solved.
Either mixture or two-phase transport modelling may be selected. In the
mixture approach a single laminar, RAS or LES model is selected to model the
momentum stress. In the Euler-Euler two-phase approach separate laminar,
RAS or LES selected models are selected for each of the phases.
Uses the flexible PIMPLE (PISO-SIMPLE) solution for time-resolved and
pseudo-transient and steady simulations.
Optional fvModels and fvConstraints are provided to enhance the simulation
in many ways including adding various sources, Lagrangian
particles, surface film etc. and constraining or limiting the solution.
SourceFiles
compressibleVoF.C
See also
Foam::solvers::fluidSolver
This greatly simplifies most setups in which it is a patch (or patches)
of the original mesh which are extruded. It prevents the need for a
topoSet configuration to convert the patch into a zone or set.
This is a better way of doing 3D thermal baffles. It does not require a
special region model and is consistent with multi-region handling in
other parts of OpenFOAM.
