fvModels should operate primarily like a list of fvModel-s, so the index
operator of relevance is the one from its list base class. This has been
made explicit to prevent ambiguity associated with the same operator in
the dictionary base class.
These permit derivations of reynolds stress models to add source terms
into the R and epsilon equations
Patch contributed by Institute of Fluid Dynamics,
Helmholtz-Zentrum Dresden - Rossendorf (HZDR)
The new fvModels is a general interface to optional physical models in the
finite volume framework, providing sources to the governing conservation
equations, thus ensuring consistency and conservation. This structure is used
not only for simple sources and forces but also provides a general run-time
selection interface for more complex models such as radiation and film, in the
future this will be extended to Lagrangian, reaction, combustion etc. For such
complex models the 'correct()' function is provided to update the state of these
models at the beginning of the PIMPLE loop.
fvModels are specified in the optional constant/fvModels dictionary and
backward-compatibility with fvOption is provided by reading the
constant/fvOptions or system/fvOptions dictionary if present.
The new fvConstraints is a general interface to optional numerical constraints
applied to the matrices of the governing equations after construction and/or to
the resulting field after solution. This system allows arbitrary changes to
either the matrix or solution to ensure numerical or other constraints and hence
violates consistency with the governing equations and conservation but it often
useful to ensure numerical stability, particularly during the initial start-up
period of a run. Complex manipulations can be achieved with fvConstraints, for
example 'meanVelocityForce' used to maintain a specified mean velocity in a
cyclic channel by manipulating the momentum matrix and the velocity solution.
fvConstraints are specified in the optional system/fvConstraints dictionary and
backward-compatibility with fvOption is provided by reading the
constant/fvOptions or system/fvOptions dictionary if present.
The separation of fvOptions into fvModels and fvConstraints provides a rational
and consistent separation between physical and numerical models which is easier
to understand and reason about, avoids the confusing issue of location of the
controlling dictionary file, improves maintainability and easier to extend to
handle current and future requirements for optional complex physical models and
numerical constraints.
A population balance suffix after the phase suffix makes determining the
phase for a given name more complex. The additional suffix is also
unnecessary as a phase can only ever belong to one population balance,
so the phase name alone uniquely idetifies the grouping.
Patch contributed by Institute of Fluid Dynamics,
Helmholtz-Zentrum Dresden - Rossendorf (HZDR)
Field corrections are effectively explicit constraints applied to the field
after solution rather than to the equation and it significantly simplifies the
implementation to treat them as a special case of constraints. To implement
this the fvOption::correct(<field>) function has been renamed
fvOption::constrain(<field>) and uses constrainsField and constrainedFields.
This replaces compressibleInterFilmFoam in a more flexible, general and easily
maintainable form. A compressibleInterFilmFoam script is provided to redirect
uses to the replacement functionality:
The compressibleInterFilmFoam solver has solver has been replaced by the more general
compressibleInterFoam solver, which now supports surface films using the new
VoFSurfaceFilm fvOption.
To run with with surface film create a system/fvOptions dictionary
containing the VoFSurfaceFilm specification, e.g.
VoFSurfaceFilm
{
type VoFSurfaceFilm;
phase water;
}
Specifying a plane with which to subset feature edges is now done using
the same dictionary syntax used elsewhere in OpenFOAM. For example, in
system/surfaceFeaturesDict:
subsetFeatures
{
// Include only edges that intersect the plane
plane
{
planeType pointAndNormal;
point (0 0 0);
normal (1 0 0);
}
...
}
The "full" filtering option in isoSurface now no longer attempts to
remove non-manifold faces. As a result, this filtering level is now
robust, but it may leave small imperfections in the surface. This has
been reinstated as the default filtering level as it has advantageous
properties over "partial" filtering in both smoothness of visualisation
and in the size of the files it generates.
A new "clean" level has been added, which does try and remove
imperfections. This is equivalent to the previous operation of the
"full" option. This is not guaranteed to be robust. In certain
configurations the removal process can propagate and delete an entire
section of the surface.