Keywords: OpenFOAM, fvOptions, Phase Change, Pure Metal Substance, Glassy Substance, Alloy Substance
When solving phase change numerically, the energy equation can be written in terms of sensible enthalpy, and a volumetric source term is added to account for the latent heat transfer in the vicinity of solidification or melting. In OpenFOAM, this source term can be taken care of using fvOptions.
The details of the code can be found here:
When applying this technique to pure metal substances, it assumes that the system is experiencing isothermal phase change, and the phase front is a sharp line. In the case of glassy or alloy substances, the phase change takes place over an extended temperature range instead of a single melting point temperature, therefore a ‘mushy’ zone exists between the solid and liquid regions. This model generates a field variable ‘alpha1’, which is the melt fraction between 0 to 1. This field can be saved and accessed in post-processing by fvOptions class name (eg: solidificationMeltingSource) followed by ‘::alpha1’