The research provide a stable, high-efficiency, high angle of attack, airfoil. The means for accomplishing these improvements is a novel,bicamberd surface profile with two or more raised ridges placed laterally to fluid flow and generally running parallel to the leading and trailing edge.A primary objective of this research is to improve the efficiency of airfoil to obtain higher ratio of useful work output to energy input, thereby saving significant energy resources. This is achieved because bicambered surface airfoil produce greater lift and reduced drag at normal operating angle of attack. A bicamber surface airfoil improved ability to retain an attached boundary layer allows a lower thickness to chord profile to give performance comparable to thicker ,single cambered surface airfoil. The above capabilities provide extensive possibilities in design of high altitude aircraft where lift coefficient is low due to thin air. Flow over a short radius object must be at a greater velocity than flow over a long radius object. There for bicambered surface airfoil effectively lower local Reynolds number is respect to boundary layer development. This stable high angle of attack airfoil is improving aviation safety. Private aircraft accident involve wing stall. Higher attack angles combined with higher lift/drag ratios would enhance glide capabilities. A secondary objective of this research is to reduce mechanical force input requires pitch airfoils such as rotary wings, propeller, rotors and impeller, saving weight in the construction. The more central aerodynamic center and low or negative pitches moment of bicambered surface airfoils allows this objective to be fulfilled. For helicopter high vehicle velocities, where high maneuverability is desired, different lift and stall properties from one side of the aircraft to the other cause problems. The anti stall characteristics to the bicambered surface airfoil can prevent much of these problems and greatly enhance the maneuverability of rotary wing vehicles.
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