Patent ID: 6467422
Filing Date: 2002-10-22
Classification: B63B,B63H,Y02T

Abstract:
An improved hydrofoil device, the hydrofoil device comprising:a first surface and a second surface located on an opposite side of the device to said first surface, wherein water flows over the first and second surfaces from a leading edge to a trailing edge of the device; and a protrusion provided adjacent the trailing edge of the device so as to produce a surface discontinuity on said first surface, wherein said protrusion comprises a protrusion surface facing the upstream direction of the hydrofoil, and the protrusion surface defines an included angle to the upstream direction of the hydrofoil of less than or substantially equal to 90Â°, whereby, in use, water flowing over the first surface is deflected back on itself by the protrusion, and a resulting increase in the local pressure on said first surface upstream of said protrusion contributes substantially to the lift generated by the hydrofoil device.