A number of changes have been made to the surfaceFieldValue and
volFieldValue function objects to improve their usability and
performance, and to extend them so that similar duplicate functionality
elsewhere in OpenFOAM can be removed.
Weighted operations have been removed. Weighting for averages and sums
is now triggered simply by the existence of the "weightField" or
"weightFields" entry. Multiple weight fields are now supported in both
functions.
The distinction between oriented and non-oriented fields has been
removed from surfaceFieldValue. There is now just a single list of
fields which are operated on. Instead of oriented fields, an
"orientedSum" operation has been added, which should be used for
flowRate calculations and other similar operations on fluxes.
Operations minMag and maxMag have been added to both functions, to
calculate the minimum and maximum field magnitudes respectively. The min
and max operations are performed component-wise, as was the case
previously.
In volFieldValue, minMag and maxMag (and min and mag operations when
applied to scalar fields) will report the location, cell and processor
of the maximum or minimum value. There is also a "writeLocation" option
which if set will write this location information into the output file.
The fieldMinMax function has been made obsolete by this change, and has
therefore been removed.
surfaceFieldValue now operates in parallel without accumulating the
entire surface on the master processor for calculation of the operation.
Collecting the entire surface on the master processor is now only done
if the surface itself is to be written out.
When using 'simple' or 'hierarchical' decomposition it is useful to slightly rotate a
coordinate-aligned block-mesh to improve the processor boundaries by avoiding
irregular cell distribution at those boundaries. The degree of slight rotation
is controlled by the 'delta' coefficient and a value of 0.001 is generally
suitable so to avoid unnecessary clutter in 'decomposeParDict' 'delta' now
defaults to this value.
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.
The pressure work term for total internal energy is div(U p) which can be
discretised is various ways, given a mass flux field phi it seems logical to
implement it in the form div(phi/interpolate(rho), p) but this is not exactly
consistent with the relationship between enthalpy and internal energy (h = e +
p/rho) and the transport of enthalpy, it would be more consistent to implement
it in the form div(phi, p/rho). A further improvement in consistency can be
gained by using the same convection scheme for this work term and the convection
term div(phi, e) and for reacting solvers this is easily achieved by using the
multi-variate limiter mvConvection provided for energy and specie convection.
This more consistent total internal energy work term has now been implemented in
all the compressible and reacting flow solvers and provides more accurate
solutions when running with internal energy, particularly for variable density
mixing cases with small pressure variation.
For non-reacting compressible solvers this improvement requires a change to the
corresponding divScheme in fvSchemes:
"div\(alphaPhi.*,p\)" -> "div\(alphaRhoPhi.*,\(p\|thermo:rho.*\)\)"
and all the tutorials have been updated accordingly.
To provide more flexibility, extensibility, run-time modifiability and
consistency the handling of optional pressure limits has been moved from
pressureControl (settings in system/fvSolution) to the new limitPressure
fvConstraint (settings in system/fvConstraints).
All tutorials have been updated which provides guidance when upgrading cases but
also helpful error messages are generated for cases using the old settings
providing specific details as to how the case should be updated, e.g. for the
tutorials/compressible/rhoSimpleFoam/squareBend case which has the pressure
limit specification:
SIMPLE
{
...
pMinFactor 0.1;
pMaxFactor 2;
...
generates the error message
--> FOAM FATAL IO ERROR:
Pressure limits should now be specified in fvConstraints:
limitp
{
type limitPressure;
minFactor 0.1;
maxFactor 2;
}
file: /home/dm2/henry/OpenFOAM/OpenFOAM-dev/tutorials/compressible/rhoSimpleFoam/squareBend/system/fvSolution/SIMPLE from line 41 to line 54.
pMin and pMax settings are now available in multiphaseEulerFoam in the
PIMPLE section of the system/fvOptions file. This is consistent with
other compressible solvers. The pMin setting in system/phaseProperties
is no longer read, and it's presence will result in a warning.
The new optional 'slash' scoping syntax is now the default and provides a more
intuitive and flexible syntax than the previous 'dot' syntax, corresponding to
the common directory/file access syntax used in UNIX, providing support for
reading entries from other dictionary files.
In the 'slash' syntax
'/' is the scope operator
'../' is the parent dictionary scope operator
'!' is the top-level dictionary scope operator
Examples:
internalField 3.4;
active
{
type fixedValue;
value.air $internalField;
}
inactive
{
type anotherFixedValue;
value $../active/value.air;
anotherValue $!active/value.air;
sub
{
value $../../active/value.air;
anotherValue $!active/value.air;
}
}
"U.*"
{
solver GAMG;
}
e.air
{
$U.air;
}
external
{
value $testSlashDict2!active/value.air;
}
active2
{
$testSlashDict2!active;
}
If there is a part of the keyword before the '!' then this is taken to be the
file name of the dictionary from which the entry will be looked-up using the
part of the keyword after the '!'. For example given a file testSlashDict containing
internalField 5.6;
active
{
type fixedValue;
value.air $internalField;
}
entries from it can be read directly from another file, e.g.
external
{
value $testSlashDict2!active/value.air;
}
active2
{
$testSlashDict2!active;
}
which expands to
external
{
value 5.6;
}
active2
{
type fixedValue;
value.air 5.6;
}
These examples are provided in applications/test/dictionary.
The the default syntax can be changed from 'slash' to 'dot' in etc/controlDict
to revert to the previous behaviour:
OptimisationSwitches
{
.
.
.
// Default dictionary scoping syntax
inputSyntax slash; // Change to dot for previous behaviour
}
or within a specific dictionary by adding the entry
See applications/test/dictionary/testDotDict.
The new multiphaseEulerFoam is based on reactingMultiphaseEulerFoam with some
improvements and rationalisation to assist maintenance and further development.
The phase system solution has been enhanced to handle two phases more
effectively and all two-phase specific models updated for compatibility so that
multiphaseEulerFoam can also replace reactingTwoPhaseEulerFoam.
When running multiphaseEulerFoam with only two-phases the default behaviour is
to solve for both phase-fractions but optionally a reference phase can be
specified so that only the other phase-fraction is solved, providing better
compatibility with the behaviour of reactingTwoPhaseEulerFoam.
All reactingMultiphaseEulerFoam and reactingTwoPhaseEulerFoam tutorials have
been updated for multiphaseEulerFoam.