Development of a high speed planing trimaran with hydrofoil support

[摘要] The successful use of hydrofoil systems on catamarans, such as the Hysucat, led to thedevelopment of a similar foil system for a high speed trimaran.Firstly a mathematical model was developed to calculate the equilibrium planing conditions of aplaning trimaran. This was then used in the hydrodynamic design of a fully planing trimaran witha design speed of 65 kn. The mathematical model was then modified to include the effects ofadded hydrofoils. This model was then used to design a hydrofoil support system for the planingtrimaran.Towing tank tests were then performed on a scale model of the boat, with and without thesupporting hydrofoil system. This was done to verify the theoretical design and to gatherresistance data, which could then be compared to other boats.The results showed a notable improvement in efficiency of the boat with the addition of foils. Theconclusion was made that with the addition of a well-designed foil system, hull efficienciessimilar to that expected for the Hysucat, can be attained when the foil system is added to thetrimaran.As this work was focused mainly on the high-speed performance of the boat, it is not certain howthe boat will perform through the speed-range. It is therefore recommended that further testing bedone, to determine the performance of the boat at lower speeds.

[发布机构] Stellenbosch University