Analysis of Horizontal Water Impact of a Rigid Body with the Air Cushion Effect

Abstract

A phenomenon of an impact of the ship section on a water free surface is examined numerically including an effect of air cushioning. Fluid flows in both the air and water domains are considered two-dimensional and solved by finite difference method. The physical model of the air is that of compressible viscous gas. The Navier-Stokes equations are written in generalized non-orthogonal curvilinear coordinates, and the Coupled Modified Strongly Implicit Procedure (CMSIP) is used in the time-varying mesh. The water domain is modelled by a viscous incompressible liquid and solved by means of the Volume of Fluid (VOF) algorithm, which is able to trace the deformations of the water free surface under the air pressure built up during the body's falling. The algorithms for the air and water domains are coupled considering the change in water free surface profile and the pressure transmission The reasonability and efficiency of the proposed approach are discussed.