Applications Of VOF Method In Two-phase Flow Simulation

In the fields of marine, aerospace and casting, we often encounter flow with two immiscible fluids. Because of the huge differences between the properties of them, the distribution of the two fluids is of significance to the computational field and therefore, a robust and general solver which is capable to capture the interface between two fluids accurately is required to complete relative analysis and design work.In this paper, a method based on an arbitrary Eulerian mesh is accepted to capture the interface between the two immiscible fluids. During the solution, two fluids are treated as one with a jump of property at their interface. The two fluids is distinguished by an indicator, the volume of fluid(VOF) fraction. The propagation is obtained by solving the transport equation of volume fraction. And the dynamics are worked out with the conservation equations of mass and momentum.By a unique density-based pressure interpolation method, the divergence encountered when solving continuity and momentum equations is avoided. Although an implicit temporal discretization scheme is used when solving velocity and pressure fields, an semi-implicit discretization scheme is utilized when solving VOF equation. To get a more accurate interface, reduce dissipation, guarantee the generality, and control the computation cost and time, the CICSAM method is used for the special discretization of volume fraction transport equation.Several cases, such as dam break, droplet, are used to estimate the accuracy and robustness of the two-phase flow solver. The ability to deal with interface merging and break is also tested. The numerical results are compared with experimental data or data on existing literature and it shows that the results are satisfactory.