Numerical simulations of water freezing processes in cavities and cylindrical enclosures

Convection and enthalpy-porosity based solidification solvers have been implemented in the Open source CFD code OpenFOAM to study water freezing phenomena in internal geometries. A polynomial water density variation has been used for the gravity related terms. Liquid to solid phase changes have been accounted for in both energy and momentum equations and the water volume fraction has been modelled with a temperature function in the domain. The models described in this paper have been compared with numerical results obtained with commercial or in-house CFD codes for a squared shape cavity and inside a cylindrical enclosure. When possible, results have also been compared to experimental measurements. This solidification solver has finally been extended and modified to create a novel formulation to account for slurry and mushy regions. It appeared clearly that physical phenomena observed in experiments could be reproduced with high accuracy when using either the solidification solver or the new slurry-mushy solidification solver. For the latter model, a distinction is made between the newly formed ice particles not interacting with each other (slurry region) and the mixture of compact ice and liquid (mushy region). The correct modelling of these two distinct regions is necessary for hydro-carbon industries for instance, where cooling oil can form wax gels.