Numerical Simulation of Multiphase Flows With Material Interface on Unstructured Grid System

Two-dimensional multiphase flows with material interface due to density difference are numerically simulated on unstructured grid system by an in-house solution code (PowerCFD). This code employs an unstructured cell-centered method based on a conservative pressure-based finite volume method and adopts a high resolution method (CICSAM) in a volume of fluid (VOF) scheme for the accurate phase interface capturing. The test cases are the Rayleigh-Taylor instability (density ratio of 2), the oil bubble rising in a partially filled container (density ratio of 2), the air bubble rising in a fully filled container with bubble shedding (density ratio of 100) and the droplet splash (density ratio of about 1000), which are typical benchmark problems among multiphase flows with material interface due to density difference. The present results are compared with other numerical solutions found in the literature. It is found that the present method simulates efficiently and accurately complex interface flow such as multiphase flows with material interface due to both density difference and instability.