Seakeeping Analysis of a High-Speed Monohull With a Motion-Control Bow Hydrofoil

The seakeeping performance is studied of a foil-assisted high-speed monohull vessel using a state-of-the-art three-dimensional Rankine panel method. The vessel is equipped with a bow hydrofoil acting as a passive heave and pitch motion-control device in waves. The formulation of the seakeeping of ships equipped with lifting appendages is developed, and the mechanisms responsible for the reduction of the heave and pitch motions of high- speed vessels equipped with hydrofoils are studied. The sensitivity of the heave and pitch motions on the longitudinal position of the hydrofoil is studied. It is found that the most efficient location for the hydrofoil is at the ship bow leading to a 50% reduction of the root mean square values of the heave and pitch motions in a Joint North Sea Wave Project (JONSWAP) spectrum. Several extensions of the analysis of the present paper are discussed. They include the reduction of the roll motion of high-speed vessels, the design of optimal active motion-control mechanisms, and the coupling of the hull form and lifting appendage design for high-speed monohull vessels.