Abstract
Influence of outrigger position of a high speed trimaran on the wave-induced motion was investigated. The trimaran is composed of the center hull with L/B = 8.0 and B/T = 3.57 where L, B and T denote the length, breadth and draft respectively, and the outriggers with l/L = 0.375 where l denotes the outrigger length. Using the trimaran model with 2.0m in ship length, tank test was carried out to capture the ship motions in regular head waves. The wave-induced motions of the trimaran, as a whole, become larger than those of the center hull which is regarded as a monohull ship. With shifting the outriggers rearward, the motion amplitude increases in the long wave-length range and decreases in the short wave-length range. Strip method excluding the hydrodynamic interactions between center hull and outriggers can capture qualitatively the change of the wave-induced motions with the outrigger position changes.
