As mentioned in Overview, the formulation in Ansys Fluent can be used to model the solidification/melting of pure materials, as well as alloys. In the case of alloys, Ansys Fluent offers two rules to determine the liquid fraction versus temperature relationship, namely the linear Lever rule and the nonlinear Scheil rule.
The following limitations apply to the solidification/melting model in Ansys Fluent:
The solidification/melting model can be used only with the pressure-based solver; it is not available with the density-based solvers.
The solidification/melting model cannot be used for compressible flows.
Of the general multiphase models (VOF, mixture, and Eulerian), only the VOF model can be used with the solidification/melting model.
With the exception of species diffusivities, you cannot specify separate material properties for the solid and liquid materials through the user interface. However, if needed, separate solid and liquid properties can be specified with user-defined functions using the DEFINE_PROPERTY macro. For details on using the DEFINE_PROPERTY macro, refer to
DEFINE_PROPERTYUDFs in the Fluent Customization Manual.When using the solidification/melting model in conjunction with modeling species transport with reactions, there is no mechanism to restrict the reactions to only the liquid region; that is, the reactions are solved everywhere.