FR3122641A1 - Device for controlling the profile of an aircraft wing, variable profile aircraft wing incorporating at least one such device and aircraft comprising at least one such wing - Google Patents

Abstract

Device for controlling the profile of an aircraft wing, variable profile aircraft wing incorporating at least one such device and aircraft comprising at least one such wing The subject of the invention is a device for controlling the profile of an aircraft wing comprising: a fixed structure (34), at least one semi-rigid skin (28) forming at least part of an upper or lower wall (16) of the wing, at least one movement system (36) positioned between the structure fixed (34) and the semi-rigid skin (28) and configured to move the semi-rigid skin (28) relative to the fixed structure (34) so as to bring the fixed structure (34) and the semi-rigid skin (28) and/or separating the fixed structure (34) and the semi-rigid skin (28). This profile control device makes it possible to vary the profile of the wing and thus modify its lift without having to modify its angle of attack. The invention also relates to an aircraft wing comprising at least one such device as well as an aircraft comprising such a wing. Picture 12

Description

Device for controlling the profile of an aircraft wing, variable profile aircraft wing incorporating at least one such device and aircraft comprising at least one such wing

The present application relates to a device for controlling the profile of an aircraft wing, to a variable-profile aircraft wing integrating at least one such device as well as to an aircraft comprising at least one such wing.

According to one embodiment, an aircraft wing profile comprises an upper surface, a lower surface, a leading edge connecting the upper surface and the lower surface at the front of the wing as well as a trailing edge connecting the upper surface and the lower surface at the rear of the wing. A wing comprises a central part with a fixed geometry and at least one front or rear flap, positioned at the level of the leading edge or the trailing edge, movable with respect to the central part in order to be able to modify the profile of the wing . These flaps are activated during the take-off and landing phases to modify the lift of the wing. When activated, these flaps generate a strong drag which increases energy losses.

The wing, and in particular its central part, has fixed geometries which are optimized to be efficient in flight in the cruising phase and for an optimized mass of the aircraft, the latter evolving with an optimized angle of attack reducing its aerodynamic drag.

As the weight of the aircraft gradually decreases during the flight due to fuel consumption, the angle of attack of the aircraft must be modified and be different from the optimized angle of attack to adapt the lift to the variation in mass. The angle of attack must also be adapted if the mass of the aircraft at take-off is different from the optimized mass.

However, the fact of making the aircraft evolve with an angle of attack different from the optimized angle of attack generates an increase in the drag and therefore in energy losses.

The present invention aims to remedy all or part of the drawbacks of the prior art.

To this end, the subject of the invention is a profile control device for an aircraft wing, said wing comprising an upper wall, a lower wall, a leading edge connecting the upper and lower walls at the front of the wing as well as a trailing edge connecting the upper and lower walls at the rear of the wing; characterized in that the profile control device comprises a fixed structure, at least one semi-rigid skin forming at least part of the upper or lower wall, at least one traction cable having first and second ends, a point of anchor, provided on an element from among the fixed structure and the semi-rigid skin, to which the first end of the traction cable is secured, a traction actuator to which the second end of the traction cable is secured, a plurality of first and second pulleys positioned between the fixed structure and the semi-rigid skin, the first pulleys being secured to the rigid structure, the second pulleys being secured to the semi-rigid skin, the traction cable being arranged to cooperate alternately with the first and second pulleys between the anchor point and the pull actuator.

This profile control device makes it possible to vary the profile of the wing and thus modify its lift without having to modify its angle of attack.

According to another characteristic, the profile control device comprises several series of pulleys each arranged in a transverse plane, the transverse planes of the different series of pulleys being parallel to each other and distributed in a longitudinal direction perpendicular to the transverse planes.

According to another characteristic, for each series of pulleys, the first and second pulleys are regularly distributed in the transverse plane, the various transverse planes of the various series of pulleys being regularly distributed along the longitudinal direction.

According to another characteristic, the profile control device comprises at least one pneumatic actuator arranged between the fixed structure and the semi-rigid skin, configured to exert a force in the direction of the semi-rigid skin.

According to another characteristic, the or each pneumatic actuator is configured to exert an adjustable force in the direction of the semi-rigid skin.

According to another characteristic, the or each pneumatic actuator comprises a flexible cylindrical enclosure trapping a pressurized gas.

According to another feature, the profile control device comprises at least one control for controlling the gas pressure inside the flexible cylindrical enclosure.

According to another characteristic, the or each flexible cylindrical enclosure extends in the longitudinal direction and is configured to cooperate with several series of pulleys.

According to another characteristic, the semi-rigid skin comprises upstream and downstream edges as well as at least one tensioning system configured to stretch the semi-rigid skin between the upstream and downstream edges.

The invention also relates to an aircraft wing comprising at least one profile control device according to one of the preceding characteristics.

According to another characteristic, the wing comprises at least one series of sensors arranged on the upper wall, distributed in a transverse direction, configured to detect a position of at least one zone of separation of an air flow flowing against the upper wall as well as at least one control integrating a control law configured to control at least one profile control device as a function of the position of the separation zone detected by the series of sensors.

Other characteristics and advantages will emerge from the description of the invention which follows, description given by way of example only, with regard to the appended drawings, among which:

is a perspective view of an aircraft,

is a section of a wing having a first profile,

is a section of the wing visible on the presenting a second profile,

is a schematic cross-section of an aircraft wing integrating a device for controlling the profile of at least part of an upper wall of an aircraft wing illustrating an embodiment of the invention,

is a schematic representation in plan view of part of the wing visible on the ,

is a schematic representation in top view of part of an aircraft wing illustrating another embodiment of the invention,

is a schematic section of a device for controlling the profile of a semi-rigid skin illustrating an embodiment of the invention, the semi-rigid skin having a first profile,

is a schematic section of the device visible on the , the semi-rigid skin having a second profile,

is a top view of the semi-rigid wall visible on the ,

is a schematic section of two profile control devices illustrating an embodiment of the invention,

is a schematic section of a portion of an upper wall of an aircraft wing illustrating an embodiment of the invention, the upper wall having a first profile, and

is a schematic section of the part of the upper wall visible on the , said top wall having a second profile.

According to an embodiment visible on the , an aircraft comprises a fuselage 10 and at least one wing 12 which has a first end 12.1 connected to the fuselage 10 as well as a free second end 12.2 opposite the first.

As illustrated in Figures 2 and 3, the wing 12 comprises a structure 14, an upper wall 16, positioned above the structure 14, forming an extrados, a lower wall 18, positioned below the structure 14, forming a lower surface, a leading edge 20 connecting the upper and lower walls 16, 18 at the front of the wing 12 as well as a trailing edge 22 connecting the upper and lower walls 16, 18 at the rear of the wing 12.

In flight, an airflow 24 flows around the wing 12, along the upper and lower walls 16, 18. This airflow 24 generates lift 26.

For the rest of the description, a longitudinal direction corresponds to the direction which extends between the first and second ends 12.1, 12.2 of the wing 12. A transverse plane is a plane perpendicular to the longitudinal direction. A transverse direction corresponds to the direction which extends between the leading and trailing edges 20, 22 and which is approximately perpendicular to the longitudinal direction and substantially horizontal when the aircraft is on the ground. A length corresponds to a dimension taken parallel to the longitudinal direction. A width corresponds to a dimension taken parallel to the transverse direction.

In a transverse plane, top wall 16 has a higher profile and bottom wall 18 has a lower profile. A profile is a generally curved line which corresponds to the intersection of the upper or lower wall 16, 18 with a transverse plane.

According to a feature of the invention, at least one profile P among the upper and lower profiles is variable.

For the rest of the description, only the upper wall 16 has a variable profile P having a first geometry at a first instant, visible on the , and a second geometry at a second instant, visible on the . Of course, the invention is not limited to this embodiment. Alternatively, only the bottom wall 18 has a variable profile or the top and bottom walls 16, 18 each have a variable profile.

The upper wall 16 comprises at least one semi-rigid deformable skin 28.

According to a first configuration visible in Figures 4 and 5, the upper wall 16 comprises a single semi-rigid skin 28 which extends between an upstream edge 28.1, close to the leading edge 20, and a downstream edge 28.2, close to the trailing edge 22. This semi-rigid skin 28 extends over the entire length of the wing 12 or over a portion of the length of the wing 12 only. The upper wall 16 may comprise a single semi-rigid skin 28 over the width of the wing 12 and several semi-rigid skins 28 distributed over the length of the wing 12.

According to a second configuration visible on the , the upper wall 16 comprises several semi-rigid skins 28, 28', 28'' which each extend between upstream and downstream edges 28.1, 28.2 approximately parallel to each other and to the longitudinal direction. These different semi-rigid skins 28, 28', 28'' can have different or identical widths. They can be juxtaposed or separated by strips of rigid material of the same width or of different widths.

According to other configurations, the upper wall 16 comprises several semi-rigid skins distributed over the width of the wing 12 and several semi-rigid skins distributed over the length of the wing 12.

The wing 12 comprises at least one profile control device 32, inserted between the structure 14 and the upper or lower wall 14, 16 with variable profile.

The wing 12 comprises, for each semi-rigid skin 28, 28, 28', at least one profile control device 32.

According to this embodiment, the profile control device 32 comprises a fixed structure 34, at least one semi-rigid skin 28, at least one movement system 36 positioned between the fixed structure 34 and the semi-rigid skin 28 and configured to move the semi-rigid skin 28 relative to the fixed structure 34 so as to bring the fixed structure 34 and the semi-rigid skin 28 closer together and/or to separate the fixed structure 34 and the semi-rigid skin 28 .

Each movement system 36 comprises at least one traction cable 40 having first and second ends 40.1, 40.2, an anchor point 42, provided on one element among the fixed structure 34 and the semi-rigid skin 28, to which is secured the first end 40.1 of the traction cable 40, a traction actuator 44, connected to the fixed structure 34, to which the second end 40.2 of the traction cable 40 is secured, a plurality of first and second pulleys 46, 48 positioned between the structure fixed 34 and the semi-rigid skin 28, the first pulleys 46 being integral with the rigid structure 34, the second pulleys 48 being integral with the semi-rigid skin 28.

The traction cable 40 is arranged so as to cooperate with a series of pulleys 50 comprising at least a first pulley 46 and at least a second pulley 48, alternately with a first pulley 46 then a second pulley 48 and so on between the point anchor 42 and pull actuator 44.

The traction actuator 44 is configured to cause the semi-rigid skin 28 and the fixed structure 34 to come together when it exerts a traction force F on the traction cable 40. On the contrary, when the traction actuator 44 releases its tensile forces on the traction cable 40, this causes a separation of the semi-rigid skin 28 and the fixed structure 34.

The fact of providing several pulleys 46, 48 distributed alternately on the fixed structure 34 and on the semi-rigid skin 28 makes it possible to reduce the tensile force F.

According to one configuration, for each traction cable 40, the first and second pulleys 46, 48 of the same series of pulleys 50 are positioned in the same transverse plane. As illustrated on the , the profile control device 32 comprises several series of pulleys 50, each cooperating with a traction cable 40, each arranged in a transverse plane, the transverse planes of the different series of pulleys 50 being parallel to each other and distributed along the longitudinal direction . The different series of pulleys 50 are regularly distributed along the longitudinal direction.

According to one arrangement, for each series of pulleys 50, the first and second pulleys 46, 48 are regularly distributed over the width (transverse direction) of the semi-rigid skin 28.

The fact of providing several pulleys 46, 48 distributed regularly according to the width and the length of each semi-rigid skin 28 allows a more homogeneous take-up of the lift 26 over the entire surface of the semi-rigid skin 28.

According to a first embodiment visible in Figures 7 and 8, the traction actuator 44 is a motorized reel. According to a second embodiment visible on the , the traction actuator 44 is a jack. Of course, the invention is not limited to these embodiments for the traction actuator 44.

As illustrated in Figures 7 and 8, the traction actuator 44 cooperates with a single traction cable 40 of a single movement system 36. Alternatively, the same traction actuator 44 cooperates with several traction cables 40 of different displacement systems 36.

According to an embodiment illustrated in the , each first or second pulley 46, 48 comprises a yoke 52 fixed to the fixed structure 34 or the semi-rigid skin 28, a sheave 54 as well as an axis of rotation 56 connecting the yoke 52 and the sheave 54, parallel to the longitudinal direction.

Of course, the displacement system 36 is not limited to the embodiments previously described. Thus, the traction cables 40 of several series of pulleys 50 could be replaced by a traction film and the first and second pulleys 46, 48 by rollers.

Each displacement system 36 comprises at least one pneumatic actuator 38, inserted between the fixed structure 34 and the semi-rigid skin 28, exerting a force in the direction of the semi-rigid skin 28. The pneumatic actuator 38 makes it possible to pre-load the movement system 36, and in particular to keep the traction cable 40 under tension. According to one embodiment, the pneumatic actuator 38 comprises a flexible cylindrical enclosure 60 trapping a gas. Whatever the embodiment, each pneumatic actuator 38 is configured and sized to always remain in contact, directly or indirectly, simultaneously with the fixed structure 34 and the semi-rigid skin 28.

According to one configuration, at least one pneumatic actuator 38 is configured to exert an adjustable force, that is to say variable. In this case, the profile control device 32, and more precisely the displacement system 36 comprises a gas supply 62 configured to supply at least one flexible cylindrical enclosure 60 of a pneumatic actuator 38 as well as at least one control 64 to control the gas pressure inside the flexible cylindrical enclosure 60.

Thus, as illustrated in Figures 7 and 8, each flexible cylindrical enclosure 60 has a given section depending on the gas pressure. By way of example, the flexible cylindrical enclosure 60, located on the right in FIGS. 7 and 8, has a first section at a first given pressure, as illustrated in the , and a second section, higher than the first section, at a second given pressure higher than the first given pressure, as illustrated in the .

According to another configuration, the force of each pneumatic actuator 38 is not adjustable. Each pneumatic actuator 38 comprises a constant stiffness, the stiffness being the ratio between the force exerted by the pneumatic actuator 38 and its compression ratio. According to this configuration, the volume of gas trapped in the flexible cylindrical enclosure 60 is constant. Depending on the case, the pneumatic actuators 38 of the same movement system 36 have identical or different stiffnesses from one pneumatic actuator 38 to another.

According to one embodiment, the displacement system 36 comprises several pneumatic elements 38 and in particular several flexible cylindrical enclosures 60.

According to one configuration, each flexible cylindrical enclosure 60 extends in a direction substantially parallel to the longitudinal direction. According to one embodiment, each flexible cylindrical enclosure 60 is positioned in line with a second pulley 48, between the fixed structure 34 and the yoke 52 of the second pulley 48 so as not to interfere with the traction cable 40 or the sheave 54 of the second pulley 48.

According to one embodiment, each flexible cylindrical enclosure 60 has a length enabling it to cooperate with several series of pulleys 50.

According to the invention, it is possible to adjust the spacing between the semi-rigid skin 28 and the fixed structure 34 by adjusting the traction force F exerted by the traction actuator 44. Thus, if the force of traction F increases, the semi-rigid skin 28 approaches the fixed structure 34. If the tensile force F decreases, the semi-rigid skin 28 moves away from the fixed structure 34.

If the pneumatic actuators 38 have different stiffnesses or exert adjustable forces, it is possible to adjust the orientation of the semi-rigid skin 28 with respect to the fixed structure 34. Thus, it is possible to tilt the semi-rigid skin -rigid 28 with respect to the fixed structure 34 by increasing the force exerted by at least one pneumatic actuator 38 and keeping it constant for at least one other pneumatic actuator 38.

As illustrated on the , when the upper panel 16 comprises first and second semi-rigid skins 28, 28' juxtaposed at a juxtaposition plane PJ, the displacement systems 36 of the first and second semi-rigid skins 28, 28' are symmetrical by relative to the plane of juxtaposition PJ and controlled by the same traction actuator 44 to obtain a change in the synchronized positioning of the first and second semi-rigid skins 28, 28' and to avoid a shift between a first spacing between the first semi-rigid skin 28 and the fixed structure 34 at the level of the plane of juxtaposition PJ as well as a second spacing between the first semi-rigid skin 28 and the fixed structure 34 at the level of the plane of juxtaposition PJ.

According to an embodiment visible in Figures 11 and 12, the upper wall 16 comprises a single semi-rigid skin 28 which extends between an upstream edge 28.1 and a downstream edge 28.2. In addition, the wing 12 comprises first, second and third profile control devices 32.1, 32.2, 32.3 distributed between the upstream and downstream edges 28.1, 28.2, the first profile control device 32.1 adjoining the upstream edge 28.1, the third profile control device 32.3 adjoining the downstream edge 28.2, the second profile control device 32.2 being interposed between the first and third profile control devices 32.1, 32.3.

When the traction actuators 44 of the various profile control devices 32.1, 32.2, 32.3 exert the same traction forces F and the same applies to the pneumatic actuators 38, the spacing between the semi-rigid skin 28 and the fixed structure 34 is substantially constant over the entire width of the semi-rigid skin 28, as illustrated in the . In this case, the upper wall 14 has a first profile adapted to a first lift, as illustrated in the .

If the traction force F exerted by the traction actuator 44 of the second profile control device 32.2 decreases and the pneumatic actuators 38 of the second profile control device 32.2 exert equal forces then the part of the skin semi- rigid 28 located to the right of the second profile control device 32.2 deviates from the fixed structure 34 while remaining parallel to the latter, as illustrated in the .

If the traction force F exerted by the traction actuator 44 of the first profile control device 32.1 decreases and, for the latter, the force exerted by at least one pneumatic actuator 38, the closest to the downstream edge 28.2 , increases and the force exerted by at least one pneumatic actuator 38, close to the upstream edge 28.1, remains constant or decreases then the part of the semi-rigid skin 28 located to the right of the first profile control device 32.1 tilts , the spacing between the semi-rigid skin 28 and the fixed structure 34 at the upstream edge 28.1 being smaller than that provided at the level of the second profile control device 32.2.

If the traction force F exerted by the traction actuator 44 of the third profile control device 32.3 decreases and that, for the latter, the force exerted by at least one pneumatic actuator 38, the closest to the upstream edge 28.1 , increases while the force exerted by at least one pneumatic actuator 38, close to the downstream edge 28.2, remains constant or then decreases the part of the semi-rigid skin 28 located to the right of the third profile control device 32.3 tilts , the spacing between the semi-rigid skin 28 and the fixed structure 34 at the level of the downstream edge 28.2 being smaller than that provided at the level of the second profile control device 32.2.

Thus, as illustrated in the , the upper wall 16 has a second curved profile different from the first profile, making it possible to increase the lift 26 as illustrated in the .

According to one configuration, the fixed structure 34 of the profile control device 32.1, 32.2, 32.3 corresponds to the structure 14 of the wing 12.

Whatever the embodiment, each semi-rigid skin 28 has a certain flexibility to be able to bend, while being rigid enough not to float like a canvas.

According to one embodiment, the semi-rigid skin 28 is configured to be able to stretch elastically in order to be able to increase the distance separating its upstream and downstream edges 28.1, 28.2 in a transverse plane.

According to another embodiment visible in Figures 4 and 5, the semi-rigid skin 28 comprises at least one tensioning system 66 to stretch the semi-rigid skin 28 between its upstream and downstream edges 28.1, 28.2. According to one configuration, the upstream edge 28.1 of the semi-rigid skin 28 is fixed and connected directly or indirectly to the structure 14 of the wing 12. In parallel, the downstream edge 28.2 of the semi-rigid skin 28 is connected to the system voltage 66. According to another configuration, the downstream edge 28.2 of the semi-rigid skin 28 is fixed and connected directly or indirectly to the structure 14 of the wing 12. In parallel, the upstream edge 28.1 of the semi-rigid skin 28 is connected to tension system 66.

According to one particularity, the tensioning system 66 of the semi-rigid skin 28 is separate from the displacement system 36. Insofar as in operation, the displacement system 36 takes up the majority of the stresses linked to the lift, the tensioning system 66 is virtually unaffected by the constraints linked to lift.

According to the invention, the profile control device 32 makes it possible to vary the profile of the upper wall 16 and thus to modify the lift of the wing 12 without having to modify its angle of attack.

According to one configuration, the wing 12 comprises at least one control configured to control at least one profile control device 32 and more particularly its traction actuators 44 and its pneumatic actuators 38.

According to one configuration, the wing 12 comprises at least one series of sensors 68 provided on the upper wall 16, distributed along a transverse direction, configured to detect a position of at least one air flow separation zone 24. According to this configuration, the control of the profile control device 32 incorporates a control law configured to control at least one profile control device 32 in order to automatically and autonomously adjust the profile of the upper wall 16, by controlling the actuators traction 44 and the pneumatic actuators 38, depending on the position of the separation zone detected by the series of sensors 68.

Thus, the profile control device 32 makes it possible to adjust the lift force in real time and to eliminate any separations of the air flow by automatically adjusting the profile of the wing 12.

Claims (10)

Device for controlling the profile of an aircraft wing, said wing (12) comprising an upper wall (16), a lower wall (18), a leading edge (20) connecting the upper and lower walls (16, 18) at the front of the wing (12) as well as a trailing edge (22) connecting the upper and lower walls (16, 18) at the rear of the wing (12); characterized in that the profile control device (32) comprises a fixed structure (34), at least one semi-rigid skin (28) forming at least a part of the upper or lower wall (16, 18), at least a traction cable (40) having first and second ends (40.1, 40.2), an anchor point (42), provided on one element among the fixed structure (34) and the semi-rigid skin (28), to which is secured the first end (40.1) of the traction cable (40), a traction actuator (44) to which is secured the second end (40.2) of the traction cable (40), a plurality of first and second pulleys (46, 48) positioned between the fixed structure (34) and the semi-rigid skin (28), the first pulleys (46) being integral with the rigid structure (34), the second pulleys (48) being integral with the semi-rigid skin (28), the traction cable (40) being arranged to cooperate alternately with the first and second pulleys (46, 48) between the poi anchor (42) and pull actuator (44). Profile control device according to the preceding claim, characterized in that the profile control device (32) comprises several series of pulleys (50) each arranged in a transverse plane, the transverse planes of the different series of pulleys (50) being parallel to each other and distributed in a longitudinal direction perpendicular to the transverse planes. Profile control device according to the preceding claim, characterized in that, for each series of pulleys (50), the first and second pulleys (46, 48) are regularly distributed in the transverse plane and in that the different transverse planes of the different series of pulleys (50) are regularly distributed along the longitudinal direction. Profile control device according to one of the preceding claims, characterized in that the profile control device (32) comprises at least one pneumatic actuator (38) arranged between the fixed structure (34) and the semi-rigid skin ( 28) and configured to exert a force in the direction of the semi-rigid skin (28). Profile control device according to the preceding claim, characterized in that the or each pneumatic actuator (38) is configured to exert an adjustable force in the direction of the semi-rigid skin (28). Profile control device according to the preceding claim, characterized in that the or each pneumatic actuator (38) comprises a flexible cylindrical enclosure (60) trapping a pressurized gas and in that the profile control device (32) comprises at at least one control (64) for controlling the gas pressure inside the flexible cylindrical enclosure (60). Profile control device according to one of Claims 2 or 3 and Claim 6, characterized in that the or each flexible cylindrical enclosure (60) extends in the longitudinal direction and is configured to cooperate with several series of pulleys ( 50). Profile control device according to one of the preceding claims, characterized in that the semi-rigid skin (28) comprises upstream and downstream edges (28.1, 28.2) as well as at least one tensioning system (66) configured to stretch the semi-rigid skin (28) between the upstream and downstream edges (28.1, 28.2). Aircraft wing comprising at least one profile control device according to one of the preceding claims. Aircraft wing according to Claim 9, characterized in that the wing (12) comprises at least one series of sensors (68) arranged on the upper wall (16), distributed along a transverse direction and configured to detect a position of at least one separation zone for an air flow (24) flowing against the upper wall (16) as well as at least one control integrating a control law configured to drive at least one profile control device depending on the position of the detachment zone detected by the series of sensors (68).