Propulsive Performance of a Container Ship in Waves (3rd Report)

Abstract

With a ship model of single screw high speed container ship, resistance and self-propulsion tests in regular head waves are carried out in the Experiment Tank of Osaka University. The experimental results of ship motions and resistance increases in regular head waves are compared with the results obtained from the theoretical calculations. The self-propulsion factors in regular head waves are analysed by assuming that the mean characteristics of a propeller in waves are identical with those in still water. The effects of wave height on ship motions, mean increases of resistance, proppeler thrust, torque and revolution, self-propulsion factors and propeller load fluctuation are investigated. The measured amplitudes of propeller load fluctuation are compared with the values caluculated by using the open water characteristics in still water, taking the axial inflow velocity to the propeller, the wave height reduction of incident wave at the stern and the response of the prime mover into consideration.