Effect of deadrise angles on hydrodynamic performance of a stepped hull

Abstract

Stepped planning hulls are commonly used on fast planning boats and water-based aircraft, but numerical means for simulating their hydrodynamics are rather limited. In this study, a panel method involving hydrodynamic sources has been applied for modeling a stepped planning hull and accounting for water surface deformations in the air-ventilated cavity and surrounding water domain. Parametric calculations have been carried out for a selected hull with variable deadrise angles and at two speed regimes. Results are shown for the boat attitude, lift–drag ratio, and drag components. The variations of the wetted surfaces on two bodies of a stepped hull are also presented and related to variations in hydrodynamic characteristics of the hull.