A coastal SWATH ship carrying 350 passengers with a cruising speed of 30 knots in a sea state of 4 has been jointly developed by Samsung and Pusan National University. The operating route is between Pohang and Wooleng island in the east sea of Korean peninsular which is known to be a harsh sea environment. The present paper is to describe the seakeeping analysis of the design ship by means of computations and experiments. A potential based 3-D panel method is used to develop a computational method which can predict the 6-degree of freedom motion responses of a SWATH ship travelling in waves at an arbitrarily heading angle. An empirical cross flow effect of the submerged bodies is taken into account together with the stabilizing fins effect. The motion responses measured in regular head waves with a 1/18 scale model are compared with the computational results. Based on the motion responses in regular waves, the seakeeping qualities of the design SWATH in the operating seas are analysed by the spectrum analysis.
The need to develop high speed marine vehicles is growing due to the increase of the world sea trade and passenger transit and also due to its fast transportation demand. Due to the limit in increasing speed beyond a certain level by the conventional hull concept, new types of high speed hull forms have been developed worldwide. A good seakeeping quality seems to be of prime important for high speed ships operating, in particular, in open seas with a long endurance. It is generally known that a catamaran is a good hull form for high speed in view of stability, seakeeping and speed performance. The increased number of building high speed catamarans in these days seems to reflect this claim.
