Resources Contact Us Home
Vorticity cancellation at trailing edge for induced drag elimination

Image Number 4 for United States Patent #7134631.

Wing tip vortices are evident from airliner vapor trails, and helicopter blade slap. Elliptically loaded high aspect ratio tapered wings have minimum induced drag but cannot eliminate it. Different methods are disclosed herein, for upper and lower surface boundary layers to cancel their opposing vorticity upon shedding from the trailing edge, thereby eliminating wake vorticty, induced drag and associated noise. This requires wing-rotor-propeller or fan blades with a platform designed for uniform bound circulation and with boundary layer control near the tip. In addition this requires special techniques to counter span-wise pressure gradients, such as tip circulation control blowing or an upwind small propeller or wind turbine on each tip. These techniques can eliminate wake vorticity with its induced drag, noise, flying on the backside of the power curve and the option for asymmetric loading by pneumatic means to eliminate need for cyclic pitch control or conventional ailerons.

  Recently Added Patents
Systems and methods for managing and utilizing excess corn residue
Warm air generating apparatus, sheet feeding apparatus, and image forming apparatus including warm air generating apparatus and sheet feeding apparatus
Oxidative coupling of hydrocarbons as heat source
Regenerative power storage system mounted on DC electric railway car
3D IC method and device
ZnO green luminescent material and its preparation
Actuator, actuator structure and method of manufacturing actuator
  Randomly Featured Patents
Cryptographic key escrow system having reduced vulnerability to harvesting attacks
Method of forming a thin film transistor having openings formed therein
Process and apparatus for molding jewelry
Non-uniform subaperture polishing
Methods and devices for airway tree labeling and/or matching
Reactive compositions including metal
Practice projectile
Multi-anode detector with increased dynamic range for time-of-flight mass spectrometers with counting data acquisition
Cyclic shift delay (CSD) short training field (STF) for orthogonal frequency division multiplexing (OFDM) signaling within multiple user, multiple access, and/or MIMO wireless communicaitons
Method for producing (R,Z)-5-tetradecen-4-olide