Experimental towing tank tests on high speed displacement ship

Abstract

In the preliminary ship design stage certain methods are needed in order to predict the hydrodynamic resistance of the ship. An accurate estimation is important in order to ensure fulfilment of contractual requirements and minimize the costs of building and operating the ship and to design an eco-efficient ship. Eco-efficiency is getting increasingly important these days because of the increasing legislative requirements for a cleaner and greener shipping industry. The improvement of resistance and performance of high-speed mono-hull forms has been of interest for Naval Architect in the past decades. In consequence, a considerable amount of effort has been carried out in this area by using different devices to reduce the fuel consumption. The accurate evaluation of ship performance is mainly based on towing tank tests followed by extrapolation methods and correlation factors. The present work focuses on the reduction of ship resistance of a fast displacement ship using an interceptor. Towing tank tests has been performed for Froude numbers between 0.23 and 0.69 to evaluate the ship resistance, the pitch and the heave of the ship. In order to reduce the ship resistance, but also the amplitude of the ship motions, an interceptor has been mounted on the hull transom. Finally, comparative analysis revealed that the interceptor can reduce the ship resistance up to 14% mainly for the Froude numbers higher than 0.4. The model tests have been carried out at Galati University Towing Tank.