Computational Study on the Hydrodynamic Effects of Interceptors Fitted to Transom of Planing Vessel

Abstract

The use of stern flaps, either fixed or controllable and interceptors in high-speed boats, has become an acceptable option to control the running trim of the vessel to enhance its speed and powering performance. The interceptor changes the pressure distribution underneath the hull over a certain distance forward of the transom. The stern interceptor effect on planing craft performance depends on its parameters and also on those of the craft. The aim to improve the performance on already built high-speed crafts has become an important issue for ecological and economic aspects. So, an in-depth study of the hydrodynamic behaviour of interceptor is essential, before it is adapted to a vessel, to get the best performance during the craft operation. Computational fluid dynamics (CFD) is being used for modelling ship flows due to the advances in computational methods. The aim of this paper is to predict the pressures and resistance characteristics of a high-speed planing craft equipped with an interceptor. The data regarding trim and resistance is generated for a planing hull with interceptor using CFD. In view of the above, an interceptor with 1 mm height is used to study the performance of a planing hull and compared with the experimental studies of Savitsky, Steen, and Srikanth. The numerical model predicts favourable trim and reduced drag for the planing hull with an interceptor.