Numerical Simulation of Vapor-Liquid Phase Flow and Vapor-Liquid Phase Change

摘要

By using the VOF method to calculate free surface and CSF model to treat surface tension, the numerical simulation of the rising bubble in water was accomplished. The results show that the bubble transforms and rotates during rising in the water, and its trajectory changes from straight to harmonic motion with its velocity increasing. The phenomenon coincides well with the experimental observation. The evaporation and condensation processes were also simulated by programming the user-defined function (UDF) as source terms of the heat and mass transfer equations, and a case study was carried out to verify the feasibility of the mathematical model presented to simulate the vapour-liquid phase change process.