A coupled level set and volume-of-fluid method for the buoyancy-driven motion of fluid particles

A level set method is combined with the volume-of-fluid method so that the coupled method not only can calculate an interfacial curvature accurately but also can achieve mass conservation well. The coupled level set and volume-of-fluid (CLSVOF) method is applied to the buoyancy-driven motion of fluid particles. For its easy and efficient implementation, we develop a complete and efficient interface reconstruction algorithm which is based on the explicit relationship between the interface configuration and the fluid volume function. Also, a cubic-interpolated propagation (CIP) scheme is combined with the CLSVOF method to calculate the advection terms of the momentum equation accurately. The improved CLSVOF method is applied for numerical simulation of bubbles and drops rising or falling in a quiescent fluid. The numerical results are found to preserve mass conservation and to be in good agreement with the data reported in the literature.