NUMERICAL AND SEMI-EMPIRICAL MODELING OF PARTICLES UNDERGOING PHASE CHANGE UNDER THE INFLUENCE OF CONVECTION

Abstract

This work is devoted to the development and validation of subgrid models describing heat and mass transfer between the bulk flow of gas/liquid and a moving particle undergoing phase change under the influence of free/mixed/forced convection. Such kind of submodels plays the role of ’scale bridges’ between microscale (e.g. interfacial phenomena) and macroscale phenomena (e.g. continuous casting). Applied to the multiscale modeling, our new model serves as a coupling between equations describing particle movement in Lagrangian space and mass, momentum, heat and species conservation equations defining melt flow in Eulerian space. Input parameters are Reynolds number (Re), Grashof number (Gr), Stefan number (Ste) and Prandtl number (Pr). The models have been validated against experimental data published recently in the literature applied to the melting of spherical and cylindrical ice particle under different flow conditions. Good agreement between numerical predictions and experimental data is observed. Additionally, some of the experiments are repeated numerically using CFD-based particle-resolved simulations. Basic flow features are discussed. Finally, the models developed for a single particle can be adopted for multi-particles systems.