Interfacial Analysis and Development of Phase Change Models for Condensation in Openfoam

Interfacial mass and heat transfer are a critical issue for phase change models. In this study, derived from basic heat conduction equations, the characteristics of vapor-liquid interface for three typical phase change models (Lee model, energy balance model, and temperature recovery model) were analyzed. Based on the open-source toolbox OpenFOAM, numerical investigations using the volume of fluid method were conducted on the influence of the heat source term and the thermal conductivity on the interfacial temperature. On this basis, a new energy balance model including vapor-liquid thermal conductivity ratio is proposed to consider the vapor thermal conductivity. Furthermore, a temperature correction term is added to stabilize the interfacial temperature to saturation temperature, where one phase is unsaturated and the other is supersaturated. The simulation results of the proposed model agree well with the analytical solution of the one-dimensional Stefan problem and Nusselt film condensation problem