Numerical Simulation of Phase–change Heat Transfer Problems Using Heat Fluxes on Phase Interface Reconstructed by Contour-Based Reconstruction Algorithm

The numerical analysis of phase–change heat transfer is challenging owing to the multiple inherent limitations of solution procedures for a finite-sized mesh system. For instance, the cell face or node point is not coincident with the phase interface, and thermal-fluidic properties, such as viscosity, specific heat, and thermal conductivity, change sharply through the phase interface. In this study, we introduce a new numerical phase–change model that reflects the thermal-fluidic discontinuities through the phase interface more faithfully. The basic solution procedure is same as the one used in the previous models. However, to obtain the phase–change rate, the new model first reconstructs the phase interface shape and calculates the heat fluxes toward both phases by using the temperature data of the region surrounding the reconstructed phase interface. In this study, we first solved one- and two-dimensional Stefan problems, in addition to the bubble-growth problem. In a comparison with the results of a few existing phase–change models, the superiority of the proposed phase–change model was confirmed in terms of solution continuity and computational costs. Next, we solved flow condensation in micro- and mini-channels and quantitatively compared local variations in the quality and heat transfer coefficient with the corresponding experimental and numerical results obtained by other researchers. Our model exhibited superior consistency with the empirical correlation than the Lee model.