Blade for a turbine engine propeller, in particular a propfan engine, propeller, and turbine engine comprising such a blade
A blade for a turbine engine propeller, in particular a propfan engine, comprising a protruding part on the leading edge thereof, wherein said blade comprises means for controlling the position of the protruding part along the leading edge thereof.
1. A blade for a propeller of a turbine engine of the unducted-fan type, comprising:
a blade body having a leading edge and a trailing edge;
a protrusion disposed on the leading edge and
means for adjusting the position of the protrusion along the leading edge.
2. The blade according to claim 1 , wherein the protrusion is situated at an end of a finger that is guided in translation in a groove extending along a part of the leading edge.
3. The blade according to claim 2 , wherein the protrusion and the part of the leading edge comprising the groove are covered with a flexible membrane fixed to the blade body.
4. The blade according to claim 3 , wherein the space contained between the membrane and the leading edge of the blade is configured to maintain a vacuum.
5. The blade according to claim 3 , comprising means for lubricating an interface between the protrusion and the membrane.
6. The blade according to claim 1 , wherein the protrusion is connected to a piston rod of an actuator controlling the position adjustment of the protrusion along the leading edge.
7. A propeller comprising a plurality of blades according to claim 6 , wherein the actuator is a single actuator common to the plurality of blades, and wherein the protrusions on each of the plurality of blades are connected to the piston rod of the single actuator.
8. The blade according to claim 1 , wherein the protrusion is connected to one end of at least one cable, an opposite end of which is attached to a rotary shaft so that the cable may be coiled around said shaft.
9. The blade according to claim 8 , wherein said at least one cable is guided by at least one pulley.
10. The blade according to claim 1 , wherein the protrusion comprises a series of elements made from deformable material of the piezoelectric type.
11. The blade according to claim 10 , wherein each of said elements is connected independently to electrical supply means.
12. A propeller for an unducted-fan turbine engine, comprising a plurality of blades according to claim 1 .
13. A turbine engine of the unducted-fan type, comprising at least one propeller, the least one propeller comprising a plurality of blades according to claim 1 .
14. The turbine engine according to claim 13 , comprising a sensor mounted in the vicinity of the at least one propeller and configured to transmit information to a computer, the computer being connected to means for actuating the means for adjusting the positions of the protrusions on the blades.
15. A method for reducing the noise emissions of the turbine engine according to claim 13 , comprising: adjusting the position of the protrusion along the leading edge of each blade according to the operating conditions of the turbine engine.
16. The method according to claim 15 , wherein optimal positions of the protrusions on the blades are predetermined for a plurality of operating conditions, the method further comprising, for a given operating condition, of putting the protrusions on the blades in the corresponding predetermined optimum position.
17. The method according to claim 15 , comprising:
detecting vortices generated by the at least one propeller or detecting a noise caused by an interaction of these vortices with a surface situated downstream of the at least one propeller, and
adjusting the position of the protrusions on the blades according to said detection.