High performance aerodynamic airfoil for aircraft wing

Claim 1

An aerodynamic wing airfoil comprising non-concave upper surface and lower surface, which are disposed dissymmetrically on either side of a datum axis superposed to the chord of the airfoil, which are forwardly limited along said chord by a leading edge and rearwardly by a trailing edge, and of which the respective thicknesses are counted from said chord, wherein the lower surface and upper surface respectively comprise on the one hand a first convex region of variable curvature disposed between the leading edge and their points corresponding to the maximum lower surface and upper surface thicknesses and intended to produce, partially or totally, the acceleration and depression of the fluid, and on the other hand a second region disposed between said points corresponding to the maximum lower surface and upper surface thicknesses and the trailing edge and subdivised into a first convex zone with moderately variable curvature, disposed immediately behind said points corresponding to the maximum lower surface and upper surface thicknesses and ensuring the deceleration and rapid recompression of the fluid, and into a second zone following the first and continuing to the trailing edge, this second zone presenting a zero or substantially zero curvature and extending over at least 50% and at the most 96% of the length of the chord, said second zone continuing more weakly the deceleration and ensuring the recompression of the fluid with a pressure gradient which diminishes in the direction of flow, said maximum thicknesses being disposed from the leading edge at a distance at the most equal to 22% of the length of said chord, and the ratio between the maximum thickness of the lower surface and the maximum thickness of the upper surface being at least equal to 0.25 and at the most equal to 1.