Tutorials have been updated to use the new consistent names within the
wall boiling system. The changes are backwards compatible so all
tutorials should run both before and after this change.
This boundary condition now solves for the wall temperature by interval
bisection, which should be significantly more robust than the previous
fixed-point iteration procedure. There is a new non-dimensional
"tolerance" setting that controls how tightly this solution procedure
solves the wall temperature. The "relax" setting is no longer used.
The boundary condition no longer triggers re-evaluation of the
temperature condition in order to re-calculate the heat flux within the
solution iteration. Instead, it extracts physical coefficients from the
form of the boundary condition and uses these to form a linearised
approximation of the heat flux. This is a more general approach, and
will not trigger side-effects associated with re-evaluating the
temperature condition.
The fixedMultiphaseHeatFlux condition has been replaced by a
uniformFixedMultiphaseHeatFlux condition, which constructs a mixed
constraint which portions a specified heat flux between the phases in
such a way as to keep the boundary temperature uniform across all
phases. This can be applied to all phases. It is no longer necessary to
apply a heat flux model to one "master" phase, then map the resulting
temperature to the others. An example specification of this boundary
condition is as follows:
wall
{
type uniformFixedMultiphaseHeatFlux;
q 1000;
relax 0.3;
value $internalField;
}
The wall boiling tutorials have been updated to use these new functions,
and time-varying heat input has been used to replace the
stop-modify-restart pattern present in the single-region cases.
It is now possible to map from one field to another within the same
patch, using the mappedValue boundary condition. The restriction is that
the mapping must be from a different field, otherwise field values are
being assigned to themselves, which produces an undefined result.
The mappedValue boundary condition can now be used in place of the
copiedFixedValue condition in the multiphaseEuler module. The
copiedFixedValue condition has therefore been removed.
In addition, the error messages that result from casting a patch to its
mapping engine (mappedPatchBase) have been standardised, and made more
specific to the situation in which the mapping is applied. It may be
inappropriate, for example, to map within the same region or patch.
These cases are now identified and appropriate error messages are
generated.
The error messages have also been made IO errors, so they now provide
context with regards to the dictionary entries that they relate to.
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
