An aircraft wing split flap and a method of fairing the inner profile thereof

Abstract

The application belongs to the technical field of aircraft wing split aileron design, and particularly relates to an aircraft wing split aileron and an inner side profile modification method thereof. The aircraft wing split aileron comprises an upper movable wing surface and a lower movable aileron. The chord-wise width of the upper movable wing surface is greater than that of the lower movable aileron. When the upper movable wing surface and the lower movable aileron are closed, the outer side surfaces of the upper movable wing surface and the lower movable aileron are conformal to the wing, the trailing edge of the upper movable aileron is bent downward, the trailing edge of the lower movable aileron is wrapped, the trailing edge of the lower movable aileron is rearward shielded, and the profile at the corresponding position of the trailing edge of the lower movable aileron and the inner side of the upper movable aileron is bent upward.

Description

Technical Field

[0001] This application belongs to the field of aircraft wing split control surface design technology, specifically relating to an aircraft wing split control surface and its inner surface modification method. Background Technology

[0002] Split control surfaces are a typical feature of flying wing aircraft. They consist of an upper movable control surface 3 and a lower movable control surface 4 suspended from the trailing edge of the wing 2 via a pivot 1. These surfaces can open and close according to the actual flight requirements of the aircraft. Figure 1 As shown.

[0003] When it is necessary to reduce the observability of an aircraft, the upper movable control surface 3 and the lower movable control surface 4 of the split control surface are usually closed. However, in the current split control surface, in order to avoid differential interference between the upper movable control surface 3 and the lower movable control surface 4, there is a certain gap when the upper movable control surface 3 and the lower movable control surface 4 are closed. In addition, the upper movable control surface 3 and the lower movable control surface 4 have a relatively long chord length. When closed, under the action of aerodynamic load, the trailing edges of the upper movable control surface 3 and the lower movable control surface 4 cannot fit together, and the gap is difficult to eliminate. This will produce strong scattering similar to a cavity slit. In addition, the upper movable control surface 3 and the lower movable control surface 4 usually have equal chord widths, and the trailing edge is directly exposed to the rearward detection range. All of these will produce typical edge strong scattering, which will seriously damage the low observability of the aircraft.

[0004] This application is made in view of the aforementioned technical deficiencies. Summary of the Invention

[0005] The purpose of this application is to provide a split control surface for an aircraft wing and a method for modifying the inner surface of the control surface, so as to overcome or mitigate at least one of the known technical defects.

[0006] The technical solution of this application is:

[0007] On the one hand, it provides a split control surface for an aircraft wing, including an upper movable wing surface and a lower movable control surface;

[0008] The chord width of the upper movable wing surface is greater than the chord width of the lower movable control surface;

[0009] When the upper movable wing surface and the lower movable control surface are closed, the outer surfaces of the upper movable wing surface and the lower movable control surface are conformal to the wing, and the trailing edge of the upper movable control surface bends downward to wrap around the trailing edge of the lower movable control surface, thus blocking the trailing edge of the lower movable control surface from the rear. The trailing edge of the lower movable control surface and the corresponding part of the inner side of the upper movable control surface bend upward to match.

[0010] According to at least one embodiment of this application, in the above-described split control surface of an aircraft wing, the chordal width of the upper movable wing surface is 50-60 mm greater than the chordal width of the lower movable control surface.

[0011] According to at least one embodiment of this application, in the above-described split control surface of an aircraft wing, the chordal width of the upper movable wing surface is 55 mm greater than the chordal width of the lower movable control surface.

[0012] According to at least one embodiment of this application, in the above-mentioned split control surface of the aircraft wing, when the upper movable wing surface and the lower movable control surface are closed, the profile of the lower movable control surface with the inner side of the upper movable control surface is bent and matched with the chord direction at an angle of 30° to 40°.

[0013] According to at least one embodiment of this application, in the above-mentioned split control surface of the aircraft wing, when the upper movable wing surface and the lower movable control surface are closed, the profile of the lower movable control surface with the inner side of the upper movable control surface is bent and engaged with the chord direction at an angle of 35°.

[0014] According to at least one embodiment of this application, in the above-mentioned split control surface of the aircraft wing, when the upper movable wing surface and the lower movable control surface are closed, the surface gap between the trailing edge of the lower movable control surface and the corresponding part of the inner side of the upper movable control surface is no more than 2mm.

[0015] According to at least one embodiment of this application, in the above-mentioned split control surfaces of the aircraft wing, the inner surfaces of the upper movable wing surface and the lower movable control surface are coated with radar-absorbing paint.

[0016] According to at least one embodiment of this application, in the above-mentioned split control surface of the aircraft wing, the surface at the corresponding position of the trailing edge of the lower movable control surface and the inner side of the upper movable control surface is modified forward into a wavy curved surface.

[0017] According to at least one embodiment of this application, in the above-mentioned split control surface of the aircraft wing, the inner surface of the lower movable control surface and the upper movable control surface has a wave-shaped modification area, which includes a set of wave crests and troughs with a wavelength distance of 70-75mm.

[0018] According to at least one embodiment of this application, in the above-mentioned split control surfaces of an aircraft wing, the wave-shaped modification area of ​​the inner surface of the lower movable control surface and the upper movable control surface has a gradually rising trend in the peaks and troughs near the root of the control surface.

[0019] According to at least one embodiment of this application, in the above-mentioned split control surface of the aircraft wing, the height between the highest point of the adjacent wave crest and the lowest point of the adjacent wave trough in the wave-shaped modification area of ​​the inner surface of the lower movable control surface and the upper movable control surface is 10-20mm.

[0020] According to at least one embodiment of this application, in the above-mentioned split control surfaces of an aircraft wing, the wavy modified areas on the inner surfaces of the lower and upper movable control surfaces and the boundary areas of the unmodified areas are all smoothly transitioned.

[0021] According to at least one embodiment of this application, in the above-mentioned split control surface of the aircraft wing, the wavy modified area of ​​the inner surface of the lower movable control surface and the upper movable control surface, and the boundary of the unmodified area are smoothly transitioned by rounding corners.

[0022] On the other hand, a method for modifying the inner profile of a split control surface on an aircraft wing is provided, for modifying the inner profile of the aforementioned split control surface on an aircraft wing, including:

[0023] Step 1: Determine the boundary of the profile modification at the corresponding position between the trailing edge of the lower movable control surface and the inner side of the upper movable control surface.

[0024] Step 2: Project the inner profiles of the lower and upper movable control surfaces along the spanwise direction onto the end base surface to obtain the inner profile base curve.

[0025] Step 3: On the end base surface, within the boundary of the inner surface modification, modify the base curves of the inner surface of the lower movable control surface and the upper movable control surface into wavy curves, thereby obtaining the inner surface of the movable control surface and the upper movable control surface, and modify the inner surface of the movable control surface and the upper movable control surface accordingly.

[0026] According to at least one embodiment of this application, in the above-described method for modifying the inner surface of a split control surface of an aircraft wing, in step one, a distance of 1 / 4 of the chordal width from the trailing edge of the control surface is selected as the boundary for modifying the inner surface of the upper movable control surface, and a distance of 1 / 5 of the chordal width from the trailing edge of the control surface is selected as the boundary for modifying the inner surface of the lower movable control surface.

[0027] In step three, the design of the wave curve includes a peak and a trough, with a wave height of 15mm and a wavelength of 76mm, and a smooth transition is adopted between the boundary of the inner surface modification and the inner surface base curve.

[0028] This application has at least the following beneficial technical effects:

[0029] A method for modifying the inner surface of an aircraft wing with a split control surface is provided. The chord width of the upper movable wing surface is designed to be greater than that of the lower movable control surface. When the split control surface is closed, the trailing edge of the upper movable control surface bends downward and wraps around the trailing edge of the lower movable control surface, thus shielding the trailing edge of the lower movable control surface from the rearward detection range. This avoids directly exposing the trailing edges of both the upper and lower movable wing surfaces to the rearward detection range, reducing the strong edge scattering characteristics. Furthermore, it can shield the gap between the upper and lower movable control surfaces from the rearward, transforming the strong scattering from the cavity-like slit into the weak scattering from the discontinuous traveling wave gap, thereby effectively reducing the scattering of the control surface. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the split control surfaces on the wings of an existing aircraft.

[0031] Figure 2 This is a schematic diagram of the installation of split control surfaces on the wing of an aircraft, as provided in an embodiment of this application.

[0032] Figure 3 yes Figure 2 Sectional view at point AA;

[0033] Figure 4 This is a schematic diagram provided in an embodiment of this application;

[0034] in:

[0035] 1-Shaft; 2-Wing; 3-Upper movable control surface; 4-Lower movable control surface.

[0036] To better illustrate this embodiment, some parts in the accompanying drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. Furthermore, the drawings are for illustrative purposes only and should not be construed as limiting this application. Detailed Implementation

[0037] To make the technical solution and advantages of this application clearer, the technical solution of this application will be described in a clearer and more complete manner below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only some embodiments of this application, and are only used to explain this application, not to limit this application. It should be noted that, for ease of description, only the parts related to this application are shown in the accompanying drawings, and other related parts can be referred to the general design.

[0038] Furthermore, unless otherwise defined, the technical or scientific terms used in this application description shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms indicating direction used in this application description are used only to indicate relative direction or positional relationship; when the absolute position of the described object changes, its relative positional relationship may also change accordingly. The word "comprising" as used in this application description indicates that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, but does not exclude other elements or objects.

[0039] Furthermore, it should be noted that, unless otherwise explicitly specified and limited, terms such as "installation" and "connection" used in the description of this application should be interpreted broadly. For example, a connection can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand its specific meaning in this application according to the specific circumstances.

[0040] A type of split control surface for aircraft wings, installed on the wing, such as... Figure 2 As shown.

[0041] The chord width of the upper movable wing surface 3 is greater than the chord width of the lower movable control surface 4.

[0042] When the upper movable wing surface 3 and the lower movable control surface 4 are closed, the outer surfaces of the upper movable wing surface 3 and the lower movable control surface 4 are conformal to the wing 2 to ensure the aerodynamic shape of the wing 2. The trailing edge of the upper movable control surface 3 curves downwards, wrapping around the trailing edge of the lower movable control surface 4, thus obscuring the trailing edge of the lower movable control surface 4. The trailing edge of the lower movable control surface 4 and the corresponding inner surface of the upper movable control surface 3 curve upwards to match. Figure 3 As shown.

[0043] In the aircraft wing split control surface disclosed in the above embodiments, the chordal width of the upper movable wing surface 3 is designed to be greater than the chordal width of the lower movable control surface 4. When the split control surface is closed, the trailing edge of the upper movable control surface 3 bends downward and wraps around the trailing edge of the lower movable control surface 4, thus blocking the trailing edge of the lower movable control surface 4 in the rearward direction. This avoids directly exposing the trailing edges of the upper movable wing surface 3 and the lower movable control surface 4 to the rearward detection range, thereby reducing the strong edge scattering characteristics. Furthermore, it can block the gap between the upper movable control surface 3 and the lower movable control surface 4 in the rearward direction, transforming the strong scattering of the cavity-like slit into the weak scattering of the traveling wave discontinuity gap, thereby effectively reducing the scattering of the control surface.

[0044] In the aircraft wing split control surface disclosed in the above embodiments, when the split control surface is closed, the trailing edge of the lower movable control surface 4 and the corresponding part of the inner side of the upper movable control surface 3 are bent upwards to fit, rather than the more common right-angle fit. This can reduce the gap displacement height difference when the upper movable control surface 3 and the lower movable control surface 4 are squeezed during aircraft flight and when the split control surface is under load, reduce the height of the step formed by the squeeze, reduce the discontinuous scattering caused by the step, and at the same time reduce the gap width when the upper movable control surface 3 and the lower movable control surface 4 are stretched, reduce gap scattering, thereby ensuring the overall low detectability of the aircraft.

[0045] The chord width of the upper movable wing surface 3 is 50-60 mm greater than that of the lower movable control surface 4, and can be designed to be 55 mm. It should not be too large to ensure the aerodynamic performance of the upper movable control surface 3 and the lower movable control surface 4 when they are open.

[0046] When the upper movable wing surface 3 and the lower movable control surface 4 are closed, the profile of the lower movable control surface 4 that bends and engages with the inner side of the upper movable control surface 3 has an angle of 30° to 40° with the chord direction, specifically 35°, and should not be too large, in order to ensure the low scattering characteristics of the gap.

[0047] When the upper movable wing surface 3 and the lower movable control surface 4 are closed, the gap between the trailing edge of the lower movable control surface 4 and the corresponding part of the inner side of the upper movable control surface 3 is no more than 2mm, so as to ensure the low scattering characteristics of the gap.

[0048] The inner surfaces of the upper movable wing surface 3 and the lower movable control surface 4 are coated with radar-absorbing paint to absorb radar waves entering the gaps when the upper movable wing surface 3 and the lower movable control surface 4 are closed, thereby further reducing the scattering characteristics when the split control surfaces are closed.

[0049] The surface profile at the corresponding position of the trailing edge of the lower movable control surface 4 and the inner side of the upper movable control surface 3 is modified forward into a wavy curved surface. In this way, when the upper movable control surface 3 and the lower movable control surface 4 are closed, the curved inner surface can reflect and attenuate the radar waves entering the gap between the upper movable control surface 3 and the lower movable control surface 4 multiple times, thereby further reducing the scattering characteristics when the split control surface is closed.

[0050] To further reduce the scattering characteristics of common radar waves when the split control surfaces are closed, the wave-shaped modification area of ​​the inner surface of the lower movable control surface 4 and the upper movable control surface 3 is designed as follows:

[0051] The inner surface of the lower movable control surface 4 and the upper movable control surface 3 has a wave-shaped modification area, including a set of wave crests and troughs, with a wavelength distance of 70-75mm.

[0052] The wave-shaped modification area on the inner side of the lower movable rudder surface 4 and the upper movable rudder surface 3 shows a gradually rising trend in the wave crests and troughs near the root of the rudder surface.

[0053] The wave-shaped modification area on the inner side of the lower movable rudder surface 4 and the upper movable rudder surface 3 has a height of 10-20mm between the highest point of the adjacent wave crest and the lowest point of the wave trough.

[0054] The inner wavy modified areas of the lower movable rudder surface 4 and the upper movable rudder surface 3 have a smooth transition with the boundary of the unmodified area. Specifically, a rounded corner can be used for the smooth transition.

[0055] In a specific example, wing 2 is fixedly connected to the fuselage. The dimensions of wing 2 are 22m × 9m. The fixed wing 1 is smoothly and seamlessly connected to the split control surface, and the surface is electrically continuous. The spanwise length of the split control surface is 2295mm, the chordwise width is 1128mm, and the thickness is 300mm. Among them, the chordwise width of the upper movable control surface 3 is 1128mm, and the chordwise width of the lower movable control surface 4 is 1076mm. Referring to the following method for modifying the inner surface profile of the split control surface of an aircraft wing, the profiles at the corresponding positions of the trailing edge of the lower movable control surface 4 and the inner side of the upper movable control surface 3 are modified:

[0056] Step 1: Determine the boundary of the profile modification at the corresponding position between the trailing edge of the lower movable control surface 4 and the inner side of the upper movable control surface 3.

[0057] Specifically, the boundary for the inner surface modification of the upper movable rudder surface 3 is selected at 1 / 4 of the chordal width from the trailing edge of the rudder surface, and the boundary for the inner surface modification of the lower movable rudder surface 4 is selected at 1 / 5 of the chordal width from the trailing edge of the rudder surface.

[0058] Step 2: Project the inner surfaces of the lower movable rudder surface 4 and the upper movable rudder surface 3 along the spanwise direction onto the end base surface to obtain the inner surface base curve.

[0059] Step 3: On the end base surface, within the boundary of the inner surface modification, modify the base curve of the inner surface of the lower movable rudder surface 4 and the upper movable rudder surface 3 into a wavy curve, thereby obtaining the inner surface of the movable rudder surface 4 and the upper movable rudder surface 3, and modify the inner surface of the movable rudder surface 4 and the upper movable rudder surface 3 accordingly.

[0060] The wavy curve includes a crest and a trough, with a wave height of 15 mm and a wavelength of 76 mm. It also features a smooth transition between the inner profile modification boundary and the inner profile base curve.

[0061] In a specific study, the radar scattering characteristics of the split control surface designed using the above embodiments were compared with those of existing split control surfaces, such as... Figure 4 As shown, within the backward oblique incidence angle domain, the maximum reduction can reach 20dB, and the radar scattering level is significantly reduced.

[0062] The technical solution of this application has been described in conjunction with the preferred embodiments shown in the accompanying drawings. Those skilled in the art should understand that the scope of protection of this application is obviously not limited to these specific embodiments. Without departing from the principles of this application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of this application.

Claims

1. An aircraft wing slat, characterized in that Including the upper movable control surface (3) and the lower movable control surface (4); The chord width of the upper movable rudder surface (3) is greater than the chord width of the lower movable rudder surface (4); When the upper movable control surface (3) and the lower movable control surface (4) are closed, the outer surfaces of the upper movable control surface (3) and the lower movable control surface (4) are conformal to the wing (2), and the trailing edge of the upper movable control surface (3) bends downward to wrap around the trailing edge of the lower movable control surface (4), blocking the trailing edge of the lower movable control surface (4) from the rear, and the profile of the lower movable control surface (4) and the corresponding part of the inner side of the upper movable control surface (3) bends upward to match; The profile of the trailing edge of the lower movable rudder surface (4) and the corresponding part of the inner side of the upper movable rudder surface (3) are modified forward into a wave-shaped curved surface; The inner side of the lower movable rudder surface (4) and the upper movable rudder surface (3) has a wave-shaped modification area, and the peaks and troughs near the root of the rudder surface show a gradual upward trend. The inner surfaces of the upper movable control surface (3) and the lower movable control surface (4) are coated with wave-absorbing paint.

2. The split control surface of an aircraft wing according to claim 1, characterized in that, The chord width of the upper movable rudder surface (3) is 50~60mm greater than the chord width of the lower movable rudder surface (4).

3. The split control surface of an aircraft wing according to claim 2, characterized in that, The chord width of the upper movable rudder surface (3) is 55 mm greater than the chord width of the lower movable rudder surface (4).

4. The split control surface of an aircraft wing according to claim 3, characterized in that, When the upper movable rudder surface (3) and the lower movable rudder surface (4) are closed, the profile of the lower movable rudder surface (4) with the inner side of the upper movable rudder surface (3) is bent and fits with the chord direction at an angle of 30°~40°.

5. The split control surface of an aircraft wing according to claim 4, characterized in that, When the upper movable rudder surface (3) and the lower movable rudder surface (4) are closed, the profile of the lower movable rudder surface (4) that bends and engages with the inner side of the upper movable rudder surface (3) has an angle of 35° with the chord direction.

6. The split control surface of an aircraft wing according to claim 5, characterized in that, When the upper movable rudder surface (3) and the lower movable rudder surface (4) are closed, the gap between the trailing edge of the lower movable rudder surface (4) and the corresponding part of the inner side of the upper movable rudder surface (3) is no more than 2mm.

7. The split control surface of an aircraft wing according to claim 6, characterized in that, The inner side of the lower movable rudder surface (4) and the upper movable rudder surface (3) has a wave-shaped modification area, including a set of wave crests and troughs, with a wavelength distance of 70~75mm.

8. The split control surface of an aircraft wing according to claim 7, characterized in that, The inner surface of the lower movable rudder surface (4) and the upper movable rudder surface (3) has a wave-shaped modification area, and the height between the highest point of the adjacent wave crest and the lowest point of the wave trough is 10~20mm.

9. The split control surface of an aircraft wing according to claim 8, characterized in that, The inner surface of the lower movable rudder surface (4) and the upper movable rudder surface (3) has a wave-shaped modified area, and the boundary between the modified area and the unmodified area is smooth.

10. The split control surface of an aircraft wing according to claim 9, characterized in that, The inner surface of the lower movable rudder surface (4) and the upper movable rudder surface (3) is wavy and modified, and the boundary between them and the unmodified area is smoothed by rounding corners.

11. A method of reshaping the inboard profile of a split aileron of an aircraft wing, for reshaping the inboard profile of a split aileron of an aircraft wing as claimed in claim 10, characterised in that, include: Step 1: Determine the boundary of the profile modification at the corresponding position of the trailing edge of the lower movable control surface (4) and the inner side of the upper movable control surface (3); Step 2: Project the inner surfaces of the lower movable rudder surface (4) and the upper movable rudder surface (3) along the spanwise direction onto the end base surface to obtain the inner surface base curve; Step 3: On the end base surface, within the boundary of the inner surface modification, modify the inner surface base curves of the lower movable rudder surface (4) and the upper movable rudder surface (3) into wavy curves, thereby obtaining the inner surface of the lower movable rudder surface (4) and the upper movable rudder surface (3), and modify the inner surface of the lower movable rudder surface (4) and the upper movable rudder surface (3) accordingly.

12. The method for modifying the inner surface profile of the split control surface of an aircraft wing according to claim 11, characterized in that, In step one, the boundary of the inner surface modification of the upper movable rudder surface (3) is selected at 1 / 4 of the chord width from the trailing edge of the rudder surface, and the boundary of the inner surface modification of the lower movable rudder surface (4) is selected at 1 / 5 of the chord width from the trailing edge of the rudder surface. In step three, the design of the wave curve includes a peak and a trough, with a wave height of 15mm and a wavelength of 76mm. The boundary of the inner surface modification is smoothly transitioned to the inner surface base curve.

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