High-lift wing suitable for long-endurance fixed-wing unmanned aerial vehicle and unmanned aerial vehicle

Abstract

The invention provides a high-lift wing suitable for a long-endurance fixed-wing unmanned aerial vehicle and the unmanned aerial vehicle, and relates to the technical field of unmanned aerial vehicles. The flap is arranged on the rear edge, close to the wing root, of the main wing, a gap is formed between the flap and the main wing, and at least one of the front edge and the rear edge of the flap is of a wavy structure in the spanwise direction; the problems that in the prior art, a long-endurance fixed-wing unmanned aerial vehicle high lift device is small in maximum lift coefficient and large in take-off distance are solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of unmanned aerial vehicles, and more specifically, relates to a lift-enhancing wing suitable for a long-flight fixed-wing unmanned aerial vehicle and the unmanned aerial vehicle. Background Art

[0002] Modern long-flight fixed-wing UAVs, especially medium and large UAVs with a take-off weight of no less than 1,000 kg, are widely used in both military and civilian fields.

[0003] In the design of traditional long-flight fixed-wing UAVs, propeller power systems are mostly used. It has the characteristics of low cost, simple structure, and low fuel consumption, and is suitable for long-flight missions. Its disadvantage is that the acceleration performance during the ground takeoff phase is poor. At the same time, in order to simplify the design and reduce the weight of the structure, traditional long-flight fixed-wing UAVs mostly use simple flaps as lift-enhancing devices. The maximum lift coefficient of this type of lift-enhancing device is small, and it is impossible to effectively control the large rudder separation flow. Under the combined effect of poor takeoff acceleration performance and the small maximum lift coefficient of the lift-enhancing device, the take-off distance of traditional long-flight fixed-wing UAVs is often greater than 1000m, which makes it impossible to take off from small airports or general aviation airports, limiting the use of UAVs. Summary of the invention

[0004] The purpose of the present invention is to address the deficiencies in the prior art and provide a high-lift wing and a UAV suitable for long-flight fixed-wing UAVs, so as to solve the problems in the prior art that the maximum lift coefficient of the high-lift device of the long-flight fixed-wing UAV is small and the take-off distance is large.

[0005] In order to achieve the above object, the present invention provides a lift-enhancing wing suitable for a long-flight fixed-wing UAV, comprising:

[0006] main wing;

[0007] A flap is arranged at the trailing edge of the main wing near the wing root, a slot is formed between the flap and the main wing, and at least one of the leading edge and the trailing edge of the flap is a wavy structure in the span direction.

[0008] Optionally, the main wing includes an inner wing section and an outer wing section which are arranged in sequence along the span direction, and a mounting groove is formed at the trailing edge of the inner wing section, and the mounting groove is used for mounting the flap.

[0009] Optionally, the flap is rotationally connected to the main wing via at least one rotating mechanism and at least one driving mechanism, and the driving mechanism is used to drive the flap to rotate.

[0010] Optionally, the rotating mechanism includes a main wing connecting seat and a flap connecting seat, the main wing connecting seat is connected to the main wing, the flap connecting seat is connected to the lower side of the flap, and the main wing connecting seat is rotatably connected to the flap connecting seat.

[0011] Optionally, the driving mechanism includes a steering gear, the steering gear is connected to the main wing, and a connecting rod is provided at an output end of the steering gear, and the connecting rod is rotationally connected to the flap.

[0012] Optionally, when the leading edge of the flap is the wavy structure, the wavelength and wave height of the wavy structure are respectively 0.1-5 times and 0.05-0.3 times the chord length of the flap; when the trailing edge of the flap is the wavy structure, the wavelength and wave height of the wavy structure are respectively 0.1-5 times and 0.05-0.3 times the chord length of the flap.

[0013] Optionally, the flap includes a plurality of ribs, at least one cross beam and a skin, the plurality of ribs are arranged at intervals along the span direction, the cross beam extends along the span direction and is connected to the plurality of ribs, and the skin is covered on the outside of the ribs and the cross beam.

[0014] Optionally, the crossbeam is connected with a hinge, and the connecting rod is connected to the crossbeam through the hinge.

[0015] Optionally, the main wing connecting seat and the flap connecting seat are rotatably connected via a shaft and a bearing.

[0016] The present invention also provides a drone, comprising:

[0017] Body;

[0018] The above-mentioned high-lift wing suitable for long-flight fixed-wing UAV, the wing root of the main wing is connected to the fuselage.

[0019] The present invention provides a high-lift wing and a UAV suitable for long-flight fixed-wing UAV, and the beneficial effects are as follows: the high-lift wing suitable for long-flight fixed-wing UAV is provided with a flap at the trailing edge of the main wing near the wing root to form a single-slot flap, which belongs to the large category of single-slot flaps, and the leading edge and / or trailing edge of the flap is a wavy structure in the span direction of the wing. Compared with the traditional straight-shaped flap, such a wavy structure not only changes the appearance and performance, but also changes the lift-enhancing principle; the single-slot flap generally increases the lift coefficient in the following two ways: 1. After the flap is deflected, the wing curvature increases, and the circulation Increase; 2. Under the action of the slot flow, the flap can still maintain the attached flow when the rudder deflection angle is large. The wavy structure adopted by the flap of the present invention has a third lift-increasing principle in addition to the above two methods, namely: 3. A chord-wise vortex structure will be generated between the crests and troughs of the wavy structure, so that the airflow re-attaches to the wing surface, reducing the flow separation on the upper surface of the flap, and effectively improving the lift coefficient of the flap; the lift-increasing wing suitable for long-flight fixed-wing UAVs can better improve the maximum lift coefficient of the wing, effectively control the large rudder deflection separation flow, and shorten the take-off distance of the UAV.

[0020] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and other objects, features and advantages of the present invention will become more apparent through a more detailed description of exemplary embodiments of the present invention in conjunction with the accompanying drawings, wherein like reference numerals generally represent like components throughout the exemplary embodiments of the present invention.

[0022] Figure 1 A schematic structural diagram of a lift-enhancing wing suitable for a long-flight fixed-wing UAV according to an embodiment of the present invention is shown.

[0023] Figure 2 A schematic diagram of the three-dimensional structure of a flap of a lift-enhancing wing suitable for a long-flight fixed-wing UAV according to an embodiment of the present invention is shown.

[0024] Figure 3 A schematic diagram of the top view structure of a flap of a lift-enhancing wing suitable for a long-flight fixed-wing UAV according to an embodiment of the present invention is shown.

[0025] Figure 4 A schematic cross-sectional structure diagram of a long-flight fixed-wing UAV according to an embodiment of the present invention is shown.

[0026] Figure 5 A schematic diagram of the three-dimensional structure of a traditional rectangular airfoil is shown.

[0027] Figure 6A schematic diagram of the three-dimensional structure of a wavy wing surface suitable for a long-flight fixed-wing UAV according to an embodiment of the present invention is shown.

[0028] Figure 7 The two-dimensional cross-sectional pressure contour and streamline diagram of a traditional rectangular airfoil are shown.

[0029] Figure 8 A two-dimensional cross-sectional pressure cloud diagram and streamline diagram of a wavy wing surface suitable for a long-flight fixed-wing UAV according to an embodiment of the present invention are shown.

[0030] Description of reference numerals:

[0031] 1. Main wing; 2. Flaps; 3. Main wing connector; 4. Flap connector; 5. Servo; 6. Connecting rod; 7. Wing rib; 8. Crossbeam; 9. Skin; 10. Hinge; 11. Shaft and bearing. DETAILED DESCRIPTION

[0032] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0033] like Figure 1 As shown, the present invention provides a lift-enhancing wing suitable for a long-flight fixed-wing UAV, comprising:

[0034] main wing 1;

[0035] The flap 2 is arranged at the trailing edge of the main wing 1 near the wing root, a slot is formed between the flap 2 and the main wing 1, and at least one of the leading edge and the trailing edge of the flap 2 is a wavy structure in the span direction.

[0036] Specifically, in order to solve the problems of small maximum lift coefficient and large take-off distance of the high-lift device of long-flight fixed-wing UAV in the prior art; the high-lift wing suitable for long-flight fixed-wing UAV provided by the present invention is provided with a flap 2 at the trailing edge of the main wing 1 near the wing root to form a single-slotted flap, which belongs to the general category of single-slotted flaps. The leading edge and / or trailing edge of the flap 2 is a wavy structure in the span direction of the wing. Compared with the traditional flap 2 with a straight shape, such a wavy structure not only changes the appearance and performance, but also changes the lift-enhancing principle; the single-slotted flap generally increases the lift coefficient in the following two ways: 1. The wing bends after the flap 2 is deflected The degree increases and the circulation increases; 2. Under the action of the slot flow, the flap 2 can still maintain the attached flow when the rudder deflection angle is large. The wavy structure adopted by the flap 2 of the present invention has a third lift-increasing principle in addition to the above two methods, namely: 3. A chord-wise vortex structure is generated between the crests and troughs of the wavy structure, so that the airflow re-attaches to the wing surface, reducing the flow separation on the upper surface of the flap 2, and effectively improving the lift coefficient of the flap 2; the lift-increasing wing suitable for long-flight fixed-wing UAVs can better improve the maximum lift coefficient of the wing, effectively control the large rudder deflection separation flow, and shorten the take-off distance of the UAV.

[0037] In this embodiment, the flap 2 is connected to the main wing 1, and a slot is formed between the flap 2 and the main wing 1, forming a single-slot flap.

[0038] In this embodiment, the main wing 1 has a large aspect ratio shape, which is suitable for long-flight fixed-wing UAVs. The flap 2 has a large aspect ratio shape, and a high-lift airfoil is used in the chord direction.

[0039] Optionally, the main wing 1 includes an inner wing section and an outer wing section which are sequentially arranged along the span direction, and a mounting groove is formed at the trailing edge of the inner wing section, and the mounting groove is used for mounting the flap 2 .

[0040] Specifically, the inner wing section is closer to the wing root than the outer wing section, and the position where the trailing edge of the inner wing section and the trailing edge of the outer wing section are close to each other forms a step-like structure in the chord direction, that is, the trailing edge of the inner wing section forms a mounting groove, and the flap 2 can be installed in the mounting groove.

[0041] Optionally, the flap 2 is rotationally connected to the main wing 1 via at least one rotating mechanism and at least one driving mechanism, and the driving mechanism is used to drive the flap 2 to rotate.

[0042] Specifically, the cooperation between the rotating mechanism and the driving mechanism enables the flap 2 to rotate, thereby completing the lowering and retracting actions of the flap 2.

[0043] Optionally, the rotating mechanism includes a main wing connecting seat 3 and a flap connecting seat 4, the main wing connecting seat 3 is connected to the main wing 1, the flap connecting seat 4 is connected to the lower side of the flap 2, and the main wing connecting seat 3 is rotatably connected to the flap connecting seat 4.

[0044] Specifically, one end of the main wing connecting seat 3 is connected to a position near the trailing edge of the main wing 1, and the other end extends rearward and downward and is rotatably connected to the flap connecting seat 4 on the lower side of the flap 2, thereby realizing a single-slit installation of the flap 2 and enabling the flap 2 to perform pitch rotation.

[0045] Optionally, the driving mechanism includes a steering gear 5 , which is connected to the main wing 1 , and an output end of the steering gear 5 is provided with a connecting rod 6 , which is rotationally connected to the flap 2 .

[0046] Specifically, the extension and retraction of the output end of the servo 5 can drive the connecting rod 6 to extend and retract, and through the rotation connection between the connecting rod 6 and the flap 2 , the flap 2 is driven to rotate around the rotation axis of the main wing connecting seat 3 and the flap connecting seat 4 .

[0047] Optionally, when the leading edge of the flap 2 is a wavy structure, the wavelength and wave height of the wavy structure are 0.1-5 times and 0.05-0.3 times the chord length of the flap 2 respectively; when the trailing edge of the flap 2 is a wavy structure, the wavelength and wave height of the wavy structure are 0.1-5 times and 0.05-0.3 times the chord length of the flap 2 respectively.

[0048] Specifically, Figure 3 As shown, the wavy structure can be described by two parameters, wavelength and wave height. Both wavelength and wave height take the chord length of flap 2 as characteristic length, the wavelength ranges from 0.1 times the chord length to 5 times the chord length, and the wave height ranges from 0.05 times the chord length to 0.3 times the chord length. In the span direction of flap 2, the wavelength and wave height can be fixed values ​​or non-fixed values, that is, the waves of the wavy structure can be uniformly distributed or unevenly distributed.

[0049] Optionally, the flap 2 includes a plurality of ribs 7 , at least one cross beam 8 and a skin 9 , wherein the plurality of ribs 7 are arranged at intervals along the span direction, the cross beam 8 extends along the span direction and is connected to the plurality of ribs 7 , and the skin 9 is covered on the outside of the ribs 7 and the cross beam 8 .

[0050] Specifically, Figure 2 As shown, multiple ribs 7 are distributed along the span direction of the flap 2, and the chord length and chord-wise position of each rib 7 are used to provide positioning for the wavy structure of the leading edge and / or trailing edge of the flap 2; the cross beams 8 are distributed along the chord direction of the flap 2, and each cross beam 8 is a straight beam, and its installation position is located in the middle of the chord direction of the flap 2, not close to the wavy structure of the leading edge and / or trailing edge of the flap 2; the skin 9 is wrapped around the outside of the ribs 7 and the cross beams 8 to form the aerodynamic shape of the flap 2.

[0051] In this embodiment, the leading edge and the trailing edge of the flap 2 are both wavy structures. Figure 6 As shown, the flap 2 forms a wavy airfoil, and the formation of the wavy airfoil is related to the spaced arrangement of the ribs 7 and the wavy structure of the leading edge and the trailing edge, which will not be described in detail here.

[0052] Optionally, the cross beam 8 is connected with a hinge 10 , and the connecting rod 6 is connected to the cross beam 8 via the hinge 10 .

[0053] Specifically, the hinge 10 is arranged so that the connecting rod 6 is rotatably connected to the cross beam 8 . When the steering gear 5 drives the connecting rod 6 to extend or retract, the connecting rod 6 pushes the flap 2 to deflect, thereby completing the lowering and retracting actions of the flap 2 .

[0054] In this embodiment, if Figure 4 As shown, the steering gear 5 is installed inside the main wing 1, and the two ends of the connecting rod 6 are respectively connected to the steering gear 5 and the crossbeam 8 of the flap 2 in a hinged manner.

[0055] Optionally, the main wing connection seat 3 and the flap connection seat 4 are rotatably connected via a shaft and a bearing 11 .

[0056] Specifically, the main wing connection seat 3 and the flap connection seat 4 are connected through a shaft and a bearing 11, and the main wing connection seat 3 and the flap connection seat 4 can rotate around the shaft.

[0057] Further, such as Figures 5 to 8 As shown, Figure 5 and Figure 6 The three-dimensional structure diagram of the conventional rectangular wing surface and the three-dimensional structure diagram of the wavy wing surface of the present embodiment suitable for a long-flight fixed-wing UAV are respectively shown. Figure 7 and Figure 8 A flow field comparison of the above two different airfoils is formed; from the comparison, it can be seen that when the traditional rectangular airfoil is deflected by a large rudder, the airflow separates near the wingtip, forming a large-scale vortex structure; when the wavy airfoil is deflected by a large rudder, the airflow separates at 0.5 times the chord length of the airfoil, forming a smaller-scale vortex structure; this shows that the flap 2 in the present invention can effectively suppress the separation flow, and its influence on the separation flow characteristics of the flap 2 when the rudder deflection is large is qualitative.

[0058] The present invention also provides a drone, comprising:

[0059] Body;

[0060] The above-mentioned high-lift wing suitable for long-flight fixed-wing UAV has a main wing 1 connected to the fuselage at its root.

[0061] Specifically, the UAV adopts the above-mentioned high-lift wing suitable for long-flight fixed-wing UAVs, which can not only better improve the maximum lift coefficient of the wing, but also effectively control the large rudder separation flow and shorten the take-off distance.

[0062] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A lift-enhancing wing suitable for a long-flight fixed-wing UAV, characterized in that: include: main wing; A flap is arranged at the trailing edge of the main wing near the wing root, a slot is formed between the flap and the main wing, and at least one of the leading edge and the trailing edge of the flap is a wavy structure in the span direction.

2. The high-lift wing for long-flight fixed-wing UAV according to claim 1, characterized in that: The main wing comprises an inner wing section and an outer wing section which are sequentially arranged along the span direction. A mounting groove is formed at the trailing edge of the inner wing section, and the mounting groove is used for mounting the flap.

3. The high-lift wing for long-flight fixed-wing UAV according to claim 1, characterized in that: The flap is rotationally connected to the main wing via at least one rotating mechanism and at least one driving mechanism, and the driving mechanism is used to drive the flap to rotate.

4. The high-lift wing for long-flight fixed-wing UAV according to claim 3, characterized in that: The rotating mechanism comprises a main wing connecting seat and a flap connecting seat, the main wing connecting seat is connected to the main wing, the flap connecting seat is connected to the lower side of the flap, and the main wing connecting seat is rotatably connected to the flap connecting seat.

5. The high-lift wing for long-flight fixed-wing UAV according to claim 3, characterized in that: The driving mechanism comprises a steering gear, which is connected to the main wing. A connecting rod is provided at the output end of the steering gear, and the connecting rod is rotationally connected to the flap.

6. The high-lift wing for long-flight fixed-wing UAV according to claim 1, characterized in that: When the leading edge of the flap is the wavy structure, the wavelength and wave height of the wavy structure are 0.1-5 times and 0.05-0.3 times the chord length of the flap, respectively; when the trailing edge of the flap is the wavy structure, the wavelength and wave height of the wavy structure are 0.1-5 times and 0.05-0.3 times the chord length of the flap, respectively.

7. The high-lift wing for long-flight fixed-wing UAV according to claim 5, characterized in that: The flap includes a plurality of ribs, at least one cross beam and a skin. The plurality of ribs are arranged at intervals along the span direction. The cross beam extends along the span direction and is connected to the plurality of ribs. The skin covers the outer sides of the ribs and the cross beam.

8. The high-lift wing for long-flight fixed-wing UAV according to claim 7, characterized in that: The crossbeam is connected with a hinge, and the connecting rod is connected to the crossbeam through the hinge.

9. The high-lift wing for long-flight fixed-wing UAV according to claim 4, characterized in that: The main wing connection seat and the flap connection seat are rotatably connected via a shaft and a bearing.

10. A drone, characterized in that: include: Body; The high-lift wing suitable for a long-flight fixed-wing UAV as described in any one of claims 1 to 9, wherein the root of the main wing is connected to the fuselage.

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