Experimental Study on Porpoising of a High-Speed Planing Trimaran

Porpoising is defined as unstable coupled heave and pitch motions. In this study, seven test conditions with various longitudinal locations of the center gravity moment inertia were designed to study porpoising phenomenon a tunnel-type planing trimaran. After comparing lower speed limit for porpoising, revealed that moving forward could increase but it also amplitude pitch. Furthermore, reduction hulls effectively reduce oscillation trimaran improve stability trimarans. test, condition A5 had 15% in compared A3, decreased by 60%. Unlike conventional towing tests, experiment studied effect on after exceeding found an speed, first increased, then decreased, increased again. This defines at which increases second time critical porpoising. The generated reaching Finally, limitations curve method predict are discussed.