Study of Planing Hydrodynamics Using Strips of Transversely Variable Pressure

Abstract

A pressure strip method is developed for the prediction of hydrodynamic forces acting on planing hulls moving on the surface of calm water. Within the frame of linearized potential flow theory, the presence of a planing surface is represented by an assemblage of strips of transversely variable pressure placed on the mean free surface. The unknown pressure distribution on each strip is represented by a sine series with unknown coefficients which are determined by solving an integral equation relating the pressure distribution to the free-surface elevation underneath the planing hull. Numerical solutions are obtained for the planing of 3-D flat plate and three basic profiles of 2-D planing surfaces, which are taken as the extreme cases of large-aspect-ratio 3-D planing surfaces. The results are compared with experimental data and good agreement is achieved.