A number of improvements have been made to the population balance phase
change drift model.
- The model now checks the ordering of the phase pairs and changes the
sign of the drift rate accordingly.
- The phase change mass flux and weights are calculated for each
velocity group, so the drift rate and phase change mass flux should be
consistent for each velocity group.
- By default the phase change mass flux is distributed between the size
groups based on the interfacial area of each group. For backward
compatibility number weighting can be enabled with a new
"numberWeighted" option.
The model now requires the user to provide a list of phase pairs in the
usual parenthesised form, rather than using the name. For example:
phaseChange
{
pairs ((gas and liquid));
}
Patch contributed by Juho Peltola, VTT.
Now for transient simulations "Final" solver settings are required for ALL
equations providing consistency between the solution of velocity, energy,
composition and radiation properties.
However "Final" relaxation factors are no longer required for fields or
equations and if not present the standard value for the variable will be
applied. Given that relaxation factors other than 1 are rarely required for
transient runs and hence the same for all iterations including the final one
this approach provide simpler input while still providing the flexibility to
specify a different value for the final iteration if required. For steady cases
it is usual to execute just 1 outer iteration per time-step for which the
standard relaxation factors are appropriate, and if more than one iteration is
executed it is common to use the same factors for both. In the unlikely event
of requiring different relaxation factors for the final iteration this is still
possible to specify via the now optional "Final" specification.
This change means that getApplication still works if we have a
controlDict.orig, rather than a controlDict. This allows us to simplify
the scripting of tutorials in which the controlDict is modified.
Introduced thermalPhaseChangePopulationBalanceTwo- and MultiphaseSystem as
user-selectable phaseSystems which are the first to actually use multiple mass
transfer mechanisms enabled by
commit d3a237f560.
The functionality is demonstrated using the reactingTwoPhaseEulerFoam
wallBoilingPolydisperse tutorial.
Patch contributed by VTT Technical Research Centre of Finland Ltd and Institute
of Fluid Dynamics, Helmholtz-Zentrum Dresden - Rossendorf (HZDR).
