A Study on Evaluation of Seakeeping Performance for Passenger Ships : 4th Report: Seakeeping Performance of High-Speed Ships

Abstract

Experimental investigations on ship motions are carried out for models of high-speed passenger ships in regular head and following waves, and vomiting ratios of passengers on the ships are estimated on the basis ofthe experiments. It is found that the heaving and pitching motions in regular head wave decrease with increasing advanced speed, and that this tendency is different from the theoretical results by a Strip Method. Even in head seas, the rolling motion occurs in high speed due to reduction of the restoring moment. It is demonstrated that evaluation of seakeeping performance of high-speed passenger ships have to be done in terms of vomiting ratio, because the distribution of vomiting ratio is different from that of the vertical acceleration due to the frequency effect on vomiting.