Winglets, wingtips, законцовки, vortex turbines

http://img.docstoccdn.com/thumb/100/40866468.png [not image]

Wingtip Vortex Turbine - Patent 4917332

This invention relates generally to aircraft aerodynamics and specifically to a method and apparatus for extracting energy from the lift-induced vortex at or near the wingtips of aircraft.Under lifting conditions, an airfoil creates a vortex system which is shed along the span, with a concentrated vortex centered just behind each wingtip. This vortex is a pure by-product of lift. It is not necessary for the production of liftand is a major source of aircraft induced drag. The vortex system generated by large aircraft (above 250,000 lbs.) poses serious hazards for following aircraft. Smaller aircraft in established flight paths are affected seriously by such vortex systems.Much research has concentrated on attenuation of this lift-induced vortex. Commonly known means for dissipation or attenuation of the vortex include vertical winglets attached at the wingtips, such as the plates described in U.S. Pat. No.3,411,738 to Sargent. Various fan-like attachments designed to break up the vortical airflow at the wingtips, to reduced hazards to following aircraft, have also been tested. U.S. Pat. Nos. 3,984,070 and 3,934,844, to Patterson, Jr. and ReighartII, respectively, are representative of this type of art. The patent to Patterson, Jr. discloses a vortex-attenuating spline device attached at the wingtips. That to Reighart II describes a vortex generator which creates a vortex opposite in directionto the wingtip vortex, in effect cancelling some of its effects.These prior art attachments yield energy in a sense, in the form of decreased drag, but no means has been shown to extract from the wingtip vortex energy directly usable in an aircraft.More recently, some research has focused on the use of blades oriented transversely in the airstream vortex to dissipate vortical energy. // www.docstoc.com

Minix wing tip device promises 6% gain in fuel efficiency for airliners

Minix claims its design can save as much as 6% on an aircraft's energy costs. For a commercial Boeing 747, that equates to a saving of around 600,000 gallon... // www.gizmag.com