초록 ▼

The present invention relates to a blade profile for rotary wing of an aircraft, comprising, between the leading edge and the trailing edge, a convex upper surface and a non-concave lower surface, wherein, at the point of maximum curvature of the leading edge, the radius of curvature Ro is approxima

The present invention relates to a blade profile for rotary wing of an aircraft, comprising, between the leading edge and the trailing edge, a convex upper surface and a non-concave lower surface, wherein, at the point of maximum curvature of the leading edge, the radius of curvature Ro is approximately defined by the expression Ro=1.7 C. emax2, in which C represents the chord and emax the relative thickness of said profile and the portion of lower surface adjacent the leading edge extends to about 20% of the chord from said leading edge and presents a very small general curvature decreasing continuously in the direction of the trailing edge up to the point of minimum curvature of the lower surface. The invention is more particularly applicable to obtaining rotary wings, for example for helicopters, capable of very high performances both when hovering, and in high speed flight, as well as during manoeuvres.

대표청구항 ▼

A blade profile for rotary wing of an aircraft, comprising between the leading edge and the trailing edge, a convex upper surface and a non-concave lower surface, wherein at the point of maximum curvature of the leading edge, the radius of curvature Ro is approximately defined by the expression Ro=1

A blade profile for rotary wing of an aircraft, comprising between the leading edge and the trailing edge, a convex upper surface and a non-concave lower surface, wherein at the point of maximum curvature of the leading edge, the radius of curvature Ro is approximately defined by the expression Ro=1.7 C. emax2, in which C represents the chord and emax the maximum relative thickness of said profile, and the portion of lower surface adjacent said leading edge comprises a first lower surface zone immediately adjacent the leading edge and extending to a few percent of the chord C, in which the curvature decreases rapidly in the direction of the trailing edge and a second lower surface zone prolonging the first and extending up to about 20% of the chord from said leading edge, this second lower surface zone having a very small general curvature decreasing continuously in the direction of the trailing edge up to the point of minimum curvature of the lower surface which is located at the end of said second zone.