Influence of interceptors, stern flaps, and their combinations on the hydrodynamic performance of a deep-vee ship

Abstract

A study of the hydrodynamic performance of a deep-vee ship was performed to determine the influence of the use of stern flaps and interceptors on drag-resistance, trim, and sinkage properties of the said ship. Factors leading to changes in the resistance and attitude of the ship were analyzed in terms of the stern pressure distribution and transom flow fields. Analysis results demonstrate that both the stern flap and interceptor serve to reduce the amount of drag resistance, running trim, and sinkage of the ship, and that the drag reduction rate attained was of the order of 3–9% in the Froude number (Fr) range of 0.334–0.584. Further, resistance performance of the deep-vee ship equipped with stern flaps was observed to be better in the Fr range of 0.334–0.5; however, when Fr value exceeded 0.5, ship equipped with interceptors demonstrated an superior drag-reduction effect. The study focused on evaluation of the combined effect of the use of stern flaps and interceptors in an attempt to enhance the energy-saving capacity of ships. Results obtained via experimental and numerical analyses demonstrate that deployment of a reasonable combination of stern appendages causes significant improvement in the drag-reduction effect and trim optimization.