This article presents the results of a multiphase flow numerical calculations. The numerical modeling method used in this work includes a volume of fluid model and immersed boundary method for studying the flow structure. The simulation was carried out on a structured Cartesian adaptive grid, where the immersed boundary is a circular pipe. The volume of the liquid, based on the piecewise linear interface reconstruction, allows us to determine the liquid-liquid boundary. The Navier-Stokes equations are discretized over the entire domain using a finite-difference scheme. The possibilities of the hybrid model (Volume of Fluid model – VOF and the immersed boundary method) are demonstrated by examples in which complex topological changes in the boundary occur. The general methodology has passed a thorough series of verification tests, the results of which are presented in this paper. An application for calculating the water flow is presented.