Requires the following changes to the corresponding entry in the fvOptions dictionary:
i. Use Tsol instead Tmelt as previously to define melting temperature in
isothermal phase change (for pure substance or eutectic mixture -> Tsol = Tliq);
ii. Optionally define new Tliq > Tsol to consider liquidus temperature in
non-isothermal phase change (for miscible mixture), where previous
defined Tsol defines solidus temperature;
iii. optionally define also alpha1e to consider max eutectic melt
fraction (that should be the percentage of solvent phase changed from
initial to eutectic liquid concentration) in partially isothermal (at
Tsol=Teutectic) and non-isothermal (from Tsol=Teutectic to Tliq) phase
change (for solid not miscible mixture) (alpha1e=0 -> pure substance;
alpha1e=1 -> eutectic mixture that is strictely not permitted).
Description
This source is designed to model the effect of solidification and melting
processes, e.g. windhield defrosting.
The isotherm phase change occurs at the melting temperature, \c Tsol (= \c
Tliq). The not isotherm phase change occurs between solidus and liquidus
temperature, \c Tsol < \c Tliq respectively, as long as the melt fraction is
greater than the max eutectic melt fraction, \c alpha1e (0 =
pure_substance, 1 = eutectic_mixture is not permitted) , i.e. eutectic to
initial solvent concentration difference, where a linear eutectic melt
fraction to temperature relation is considered - lever rule.
The presence of the solid phase in the flow field is incorporated into the
model as a momentum porosity contribution; the energy associated with the
phase change is added as an enthalpy contribution.
References:
\verbatim
Voller, V. R., & Prakash, C. (1987).
A fixed grid numerical modelling methodology for convection-diffusion
mushy region phase-change problems.
International Journal of Heat and Mass Transfer, 30(8), 1709-1719.
Swaminathan, C. R., & Voller, V. R. (1992).
A general enthalpy method for modeling solidification processes.
Metallurgical transactions B, 23(5), 651-664.
\endverbatim
The model generates the field \c \<name\>:alpha1 which can be visualised to
to show the melt distribution as a fraction [0-1].
Usage
Example usage:
\verbatim
solidificationMeltingSource1
{
type solidificationMeltingSource;
active yes;
selectionMode cellZone;
cellZone iceZone;
Tsol 273;
L 334000;
thermoMode thermo;
beta 50e-6;
rhoRef 800;
}
\endverbatim
Where:
\table
Property | Description | Required | Default value
Tsol | Solidus temperature [K] | yes |
Tliq | Liquidus temperature [K] | no | Tsol
alpha1e | Max eutectic melt fraction [0-1[ | no | 0
L | Latent heat of fusion [J/kg] | yes |
relax | Relaxation coefficient [0-1] | no | 0.9
thermoMode | Thermo mode [thermo|lookup] | yes |
rhoRef | Reference (solid) density [kg/m^3] | yes |
rho | Name of density field | no | rho
T | Name of temperature field | no | T
Cp | Name of specific heat field | no | Cp
U | Name of velocity field | no | U
phi | Name of flux field | no | phi
Cu | Model coefficient [1/s] | no | 100000
q | Model coefficient | no | 0.001
beta | Thermal expansion coefficient [1/K] | yes |
g | Accelerartion due to gravity | no |
\endtable
Patch contributed by Lorenzo Trevisan and integrated by CFD Direct.
Resolves patch request https://bugs.openfoam.org/view.php?id=2907
bad26bee71