Hydrodynamic Characteristics of the Surface-Piercing Propeller for the Planing Craft

Abstract

Market demands for high-speed marine vehicles (HSMVs) are high in both commercial and naval branches. It is the naval architects’ task to design the hull and propulsion system to diminish drag, improve the propulsive efficiency, higher safety and better maneuverability. Surface Piercing Propellers (SPPs) may provide those possessions for the vehicles. Unlike immersed propellers, behavior of the SPPs is susceptible to immersed depth, Weber number and shaft inclination angle. This paper uses a specially practical and numerical method to predict the hydrodynamic characteristics of the SPPs. Critical advance ratio is obtained by practical formula, using Weber number and pitch ratio in the transition mode. Numerical method employs the potential based boundary element method (BEM) on the engaged surfaces. Two models of three and six bladed of the SPPs (SPP-1 and SPP-2) are selected and some results are shown.