| 摘要 |
The airfoil device of the invention with very high aerodynamic efficiency has a lower surface with a continuous profile and an upper surface with a discontinuous profile which reverse when tacking occurs. This device includes a central element (1) extending from the leading edge (7) to the trailing edge (8) and a flap assembly (2) overlying each side of the foremost half of the central element. This assembly (2) comprises two angularly mobile flaps (3) spaced from the central element (1). The flap which is mounted on the lower surface side lies against the central element (1) so that they form together a laminar profile. The flap (3) which is mounted on the upper surface side is deflected by the depression and presents, together with the central element (1), a discontinuous profile that forms a projection (3A) at the rear edge of the flap (3), which produces a compressed turbulence area that greatly increases the lift and partially converts the drag resistance into a propulsive force, even at a high angle of incidence. |
