A hybrid level-set based immersed boundary method for study of multi-phase flows with. moving structures

A hybrid Dual-Grid Level Set based Immersed Boundary Method (DGLSIBM) for CFD simulation of multiphase flow over a moving immersed body is presented. It aims to provide a relatively simpler yet efficient algorithm to develop and implement for computational analysis of three-phase interactions involving well-defined movement of solid structures in three-dimensions. The domain is described by combination of two explicit level-set functions: one representing normal distance function from fluid-solid interface φ_s(x^→,t), and the other demarcating liquid-gas boundary within the fluid domain φ_s(x^→,t). The governing equations are: (a) Novier-Stokes equations for incompressible multi-phase fluid flow and (b) Level-set equations far tracking the interfaces PI. Note that, for solid-fluid interface, the velocity of the solid is prescribed and hence the algorithm is applicable to one-way coupled FSI problems. (author).