A flow improvement device at the wing root side of a leading edge slat wing

Abstract

The utility model relates to a kind of flow improving devices at wing root side of front edge slat wing root, comprising: front edge slat, by support, rack, gear mechanism and wing leading edge can be retracted connection;Slat channel, be opened in the lower skin of the inner surface of the near wing root cavity of front edge slat, width than baffle joint pillar diameter 1-2mm;Slat side edge baffle, through baffle joint pillar wear slat channel;Baffle storage bin track, welding between two baffle storage bin wallboard, width than slat side edge baffle thickness 2-4mm;Baffle curved protrusion, fixed in the lower side of slat side edge baffle rear, with baffle storage bin track sliding contact;Sealing element is set to the profile of slat side edge baffle top and baffle storage bin opening edge.The utility model, using movable baffle and front edge slat coordinated motion, break through the design limit of fixed isolation piece to slat side edge, realize the drag reduction of downflow layout, cooperate sealing element to reduce airflow interference, increase stall angle of attack and maximum lift coefficient, improve aerodynamic performance.

Description

Technical Field

[0001] This utility model relates to the field of high-lift systems for aircraft, specifically a flow improvement device at the root side of a leading-edge slat. Background Technology

[0002] Leading-edge lift enhancers are key components for improving aircraft aerodynamic performance, especially crucial during low-speed flight. The lift-to-drag ratio and maximum lift coefficient during takeoff are important indicators of an aircraft's low-speed aerodynamic performance, directly impacting its safety and fuel economy. For example, higher low-speed aerodynamic performance translates to better safety and fuel economy.

[0003] As a commonly used leading-edge lift enhancement device, slats, when deployed, cause flow interference at the boundary between the slat's side edge and the fixed area of ​​the main wing, leading to flow separation on the upper surface of the wing. With the introduction of seamless slat designs for takeoff positioning, although the gap between the slat's trailing edge and the main wing is closed, improving the takeoff lift-to-drag ratio, the flow interference at the boundary between the slat's side edge and the fixed area of ​​the main wing is further aggravated, severely limiting the aircraft's low-speed aerodynamic performance.

[0004] The seamless slat design for takeoff positioning originates from the following literature: Strüber, H. THE AERODYNAMIC DESIGNOF THE A350 XWB-900 HIGH LIFT SYSTEM [C] / / 29 Congress of the International Council of the Aeronautical Sciences, 2014: Section 3.1.2. An excerpt from Section 3.1.2 is as follows:

[0005] "At take-off deployment angle, the slat trailing edge seals against the main wing nose. This keeps the drag level low, but compromises the performance in that deployment position due to the missing slot... Contour Generated Sealed Slats (CGSS) rotate around a hinge line. angle.”

[0006] The following is a translation of the excerpt from the original text: At the takeoff deployment angle, the trailing edge of the slat is sealed to the nose of the main wing. This keeps the drag level low, but the lack of a gap affects the performance of the maximum lift coefficient (C_{Lmax}) at this deployment position… The profile-generated sealed slat (CGSS) rotates about the hinge line, and the hinge radius is determined by the desired gap size at both the takeoff deployment angle (when the trailing edge of the slat is sealed to the D-shaped nose of the main wing) and the landing deployment angle.

[0007] This document describes the A350 XWB-900's outer wing leading edge as employing a "Sealed Slat" design, characterized by:

[0008] At the takeoff deployment angle (takeoff positioning), "the slat trailing edge seals against the main wing nose" and "due to the missing slot", low drag characteristics are achieved.

[0009] At the landing deployment angle (landing positioning), according to the "Contour Generated Sealed Slats (CGSS) design principle," there exists a "desired gap size at the landing deployment angle" (see...). Figure 6 ).

[0010] According to the document, the trailing edge of the slat under takeoff positioning is sealed to the nose of the main wing, and the term "SealedSlat" is introduced. This is because the slat creates a gap under landing positioning (see...). Figure 6 To distinguish this design from other different mounting positions, this application describes the design as a seamless slat design for takeoff. It is understood that the landing position is the slat fully deployed state, while the takeoff position is an intermediate angle of slat deployment, therefore the slat is not fully deployed.

[0011] To improve flow at the junction of the slat side edge and the main wing after slat deployment, inventors Zhong Min et al. from the China Academy of Aeronautical Sciences proposed, in their Chinese patent application (publication number CN110539882A), to install a first flow isolation plate and a second flow isolation plate at the combined configuration of the inner leading-edge curved flap and the outer leading-edge slat. In this technical solution, the first flow isolation plate is located between the leading-edge curved flap and the leading-edge slat, arranged along the direction of the slat's forward extension. Since the first flow isolation plate is fixedly installed on the inner surface of the leading-edge slat, the inner surface of the leading-edge slat also follows the direction of the slat's forward extension, preventing it from being arranged in the flow direction. This limits the design space for the slat side edge, leading to increased wind resistance and limiting the use of methods such as slat root shaping for lift enhancement.

[0012] The following is an explanation of some of the technical terms involved in this device:

[0013] Takeoff positioning: This refers to the specific position of lift-enhancing devices (such as slats and flaps) during the takeoff phase. During takeoff, to meet the specific lift and drag requirements, the lift-enhancing devices are adjusted to a relatively fixed deflection angle or position suitable for takeoff; this position is the takeoff positioning. When in takeoff positioning, the placement of lift-enhancing devices such as slats appropriately increases the camber and area of ​​the wings, thereby improving the wing's lift coefficient. This allows the aircraft to generate sufficient lift at lower speeds to meet the lift requirements for takeoff, shortening the takeoff run distance. It also helps the aircraft to smoothly lift off the ground and begin its initial climb after takeoff.

[0014] Leading-edge slats: Movable surfaces on the leading edge of an aircraft wing used to improve airflow at high angles of attack. Deployed during takeoff and landing, they increase wing camber and area, delaying airflow separation, increasing lift coefficient, increasing stall angle of attack, and shortening takeoff and landing distances. Leading-edge slats are typically used in conjunction with trailing-edge flaps to form the aircraft's lift-enhancing system.

[0015] Wing root: The innermost part where the wing connects to the fuselage. The structural design and aerodynamic layout of the wing root have a significant impact on the overall performance of the aircraft, and must meet requirements in terms of structural strength, aerodynamic performance, and coordination with other components.

[0016] Leading edge slat root side: refers to the lateral edge of the leading edge slat at the wing root.

[0017] Flow Improvement Device: This name, from a functional perspective, indicates that its main function is to optimize and improve the airflow at the root side edge of the leading-edge slat. Through specific design and structure, it adjusts the direction, speed, and pressure distribution of the airflow to reduce airflow separation, lower drag, and increase lift, thereby improving the aerodynamic performance of the aircraft in relevant flight phases.

[0018] The information disclosed in this background section is intended only to enhance the understanding of the general background of this utility model and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Utility Model Content

[0019] In view of the deficiencies in the existing technology, the purpose of this utility model is to provide a flow improvement device at the wing root side of the leading edge slat, which aims to solve the problem of flow separation on the upper surface of the wing caused by flow interference at the junction of the side edge and the fixed area of ​​the main wing after the leading edge slat is deployed, especially in the case of seamless slats for takeoff positioning, which limits the aircraft's stall angle of attack and maximum lift coefficient.

[0020] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0021] A flow improvement device at the root side of a leading-edge slat, characterized in that it comprises:

[0022] Leading edge slat 3 is retractable and extendable to the leading edge of the wing via a bracket, rack, and gear mechanism.

[0023] The slat channel 3.1 is opened on the lower side skin of the concave inner surface of the leading edge slat 3 near the root of the wing, and its width is 1-2 mm larger than the diameter of the diaphragm joint support 4.1;

[0024] The slat side edge partition 4 passes through the slat channel 3.1 via the partition joint support 4.1;

[0025] The partition storage compartment track 5.1 is welded and fixed between the two partition storage compartment wall panels 5.2, and its width is 2-4mm larger than the thickness of the slit side edge partition 4;

[0026] The curved protrusion 4.3 of the partition is fixed to the lower rear side of the partition 4 on the side edge of the slit wing and slides in contact with the partition storage compartment track 5.1;

[0027] A sealing element is provided on the upper contour of the slat side edge partition 4 and the edge of the partition storage compartment opening 5.3.

[0028] Based on the above technical solution, a slat channel reinforcing frame 3.2 is installed on both the inner and outer sides of the slat channel 3.1, and the reinforcing frame is connected to the skin near the slat channel 3.1 by bolts.

[0029] Based on the above technical solution, the rear part of the partition storage compartment wall panel 5.2 is bolted to the front wing beam and riveted to the upper and lower wing skins.

[0030] Based on the above technical solution, the partition joint 4.2 is connected to the partition joint support 4.1 by threads, and the spherical surface of the partition joint 4.2 slides in contact with the curved surface of the slit channel reinforcing frame 3.2.

[0031] Based on the above technical solution, the slat side edge partition 4 slides along the arc-shaped path of the partition storage compartment track 5.1 via the partition curved protrusion 4.3.

[0032] Based on the above technical solution, the partition storage compartment opening 5.3 is opened on the wing skin, and the minimum safe distance between the upper edge of the opening and all positions of the slat side edge partition 4 is ≥5mm.

[0033] Based on the above technical solution, a fluororubber seal is installed on the upper contour of the slat side edge partition 4 to seal the gap between the partition and the inner surface of the leading edge slat 3.

[0034] Based on the above technical solution, a gear-rack structure is adopted to replace the curved protrusion of the partition 4.3 and the partition storage compartment track 5.1;

[0035] The gear is fixed to the side edge partition 4 of the slat, and the rack is fixed to the inner wall of the partition storage compartment wall 5.2;

[0036] The gear is helical and its axis is perpendicular to the surface of the partition plate. Limiting blocks are provided at both ends of the rack, and the meshing area is covered with a dust cover.

[0037] Based on the above technical solution, the sealing element is made of fluororubber with a temperature resistance range of -50℃ to 200℃;

[0038] Its cross-section is elliptical, and its height is 50%-70% of the thickness of the slat side edge partition 4;

[0039] The compression amount installed at the edge of the main wing slot is 10%-15%.

[0040] Based on the above technical solution, the partition joint 4.2 is a spherical structure with a radius of 15-20mm;

[0041] The 4.3 curved protrusions on the partition are circular protrusions with a radius of 80-120mm.

[0042] The flow improvement device at the root side of the leading edge slat described in this utility model has the following beneficial effects:

[0043] By arranging baffles and other structures at the wing root side edge of the leading-edge slats and designing corresponding retraction and guidance mechanisms, the baffles can move synchronously with the retraction and extension of the slats. This can block the unfavorable airflow from the cavity of the leading-edge slats to the upper wing surface without affecting other normal operations, thereby improving the airflow quality of the upper wing surface, delaying wing separation, increasing the aircraft's maximum lift coefficient at low speeds, and enhancing the aircraft's takeoff aerodynamic performance. This helps the aircraft better meet safety and economic requirements during takeoff and landing.

[0044] This invention discloses a flow improvement device at the wing root of a leading-edge slat, used in aircraft employing slats as high-lift devices at the wing's leading edge. The device focuses on optimizing airflow at the wing root. Through the coordinated movement of the leading-edge slat body and a movable bulkhead, it constructs an aerodynamic structure that combines drag reduction and lift enhancement, thereby improving wing root flow, delaying wing separation, and enhancing the aircraft's takeoff aerodynamic performance. Applied to the leading edge of the aircraft wing, this flow improvement device addresses aerodynamic problems encountered when using leading-edge slats during low-speed flight phases such as takeoff and landing, including unfavorable phenomena like flow separation at the junction of the slat side edge and the fixed area of ​​the main wing, providing an effective solution for optimizing aircraft aerodynamic performance.

[0045] Compared with the prior art, the core technological innovation of this utility model lies in the use of a coordinated movement mechanism between a movable partition and a leading-edge slat, with the following specific advantages:

[0046] Compared to the design in CN110539882A, published by the China Academy of Aeronautical Sciences, which states that "the first flowing isolation plate is fixedly installed on the inner side of the leading edge slat and arranged along the forward extension direction of the slat," the slat side edge partition of this utility model does not need to be fixedly connected to the inner side of the slat. Instead, it is guided by structures such as slat channels and partition storage compartment tracks, and moves relative to the slat as it is extended and retracted. This design breaks through the limitation of fixed isolation plates on the shape design space of the slat side edge, allowing the slat side edge to adopt a flow-oriented layout. This reduces the wind resistance of the slat and provides more possibilities for optimization methods such as shape modification and lift enhancement at the wing root. At the same time, the cooperation of sealing components further reduces airflow interference, improving aerodynamic performance while taking into account the flexibility of structural design. Attached Figure Description

[0047] The present invention includes the following figures:

[0048] The accompanying drawings are provided to better understand this utility model and do not constitute an undue limitation on it. Wherein:

[0049] Figure 1 This invention provides a schematic diagram of the flow improvement device at the root side of a leading-edge slat (slat fully deployed).

[0050] Figure 2 This invention provides a schematic diagram of the flow improvement device at the root side of a leading-edge slat (slat part in deployed state).

[0051] Figure 3 This invention provides a schematic diagram of the flow improvement device at the root side of a leading-edge slat (slat retracted state).

[0052] Figure 4 Schematic diagram of the position of the inner leading edge slat.

[0053] Figure 5 Schematic diagram of the shape and structure of the inner leading edge slat.

[0054] Figure 6 Schematic diagram of the slat side edge partition (Form 1).

[0055] Figure 7 Schematic diagram of the slat side edge partition (Form 2).

[0056] Figure 8 Schematic diagram of the slatted side edge diaphragm seal.

[0057] Figure 9 A schematic diagram of the partition storage compartment wall panels and partition storage compartment tracks.

[0058] Figure 10 Results of low-speed wind tunnel tests.

[0059] Figure 11 Schematic diagram of the leading edge slat position.

[0060] Figure label:

[0061] 2. Leading edge of the wing; 3. Leading edge slat; 3.1. Slat channel; 3.2. Slat channel reinforcing frame; 4. Slat side edge bulkhead; 4.1. Bulkhead joint support; 4.2. Bulkhead joint; 4.3. Bulkhead curved protrusion; 4.4. Bulkhead gear; 5. Bulkhead storage compartment; 5.1. Bulkhead storage compartment track; 5.2. Bulkhead storage compartment wall panel; 5.3. Bulkhead storage compartment opening. Detailed Implementation

[0062] The present invention will be further described in detail below with reference to the accompanying drawings. This detailed description is an illustration of exemplary embodiments of the present invention, including various details of these embodiments to aid understanding, and should be considered merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present invention. Similarly, for clarity and brevity, descriptions of well-known functions and structures are omitted in the following description.

[0063] Taking the seamless slatted wing for aircraft takeoff as an example, such as Figure 1 , Figure 2 , Figure 3 As shown, the flow improvement device at the root side of the leading edge slat of this utility model includes:

[0064] Leading-edge slat 3, used to increase the wing's leading-edge camber and reduce the actual angle of attack to delay airflow separation and increase wing lift, is usually deployed in conjunction with the trailing-edge flap. It is located on the leading edge of the wing, in the inner region between the engine and the fuselage (at the wing root), and has a slender, arc-shaped structure with a crescent-shaped cross-section; there is only one slat. Figure 11 As shown, the leading edge slat 3 specifically refers to the inner leading edge slat located on the leading edge 2 of the wing, between the engine and the fuselage. The area of ​​the wing near the fuselage is called the wing root. The leading edge slat 3 is a slender arc structure with a crescent-shaped cross-section. When retracted, the inner surface of the leading edge slat 3 is in contact with the leading edge of the wing, and the overall shape is continuous to reduce cruise drag.

[0065] The slat channel 3.1 is used to guide the movement of the slat side edge partition 4. It is located on the lower side skin of the concave surface of the leading edge slat 3 near the root of the slat. It is a long strip skin opening. Its length needs to meet the movement stroke of the slat side edge partition 4. Its width is 1-2 mm larger than the diameter of the partition joint support 4.1 of the slat side edge partition 4. Its thickness is the thickness of the slat skin (1-2 mm). It has a rounded rectangular cross-section. There is only one such channel. It is opened on the leading edge slat 3 and is an integral structure with the leading edge slat 3.

[0066] The slat channel reinforcement frame 3.2 is designed to strengthen the skin near the slat channel 3.1 to withstand tensile and compressive loads. It is located on the inner and outer sides of the skin near the slat channel 3.1 and consists of two pieces. The shape is the same as that of the slat channel 3.1, but the size is slightly larger. There are two pieces in total. They are connected to the skin near the slat channel 3.1 through bolt holes and are located on the inner and outer sides of the slat channel 3.1 during assembly.

[0067] The slat side edge baffle 4 is used to reduce the gap between the slat and the leading edge slat 3 and to block the airflow. It is set on the inner surface of the leading edge slat 3 near the wing root side edge area. The overall outline shape needs to be verified by motion simulation. The slat side edge baffle 4 does not need to bear too much rigidity and sealing requirements. It does not interfere with the leading edge slat 3 (minimum safe distance ≥5mm). The length is 80%-90% of the length of the slat side edge, the height is more than 90% of the height of the slat side edge, the thickness is 2-3cm, and there is only one. It slides in contact with the leading edge slat 3 through the baffle joint support 4.1 and the baffle joint 4.2. It has no independent power and is driven by the power of the leading edge slat 3. The slat side edge partition 4 slides downward or upward within the slat channel reinforcing frame 3.2 via the partition joint support 4.1 and the partition joint 4.2. Due to the three-dimensional shape of the slat channel reinforcing frame 3.2, it tends to move outward or inward, thereby realizing the transmission of power. Its limit is achieved by the limit of the partition joint 4.2 by the slat channel reinforcing frame 3.2 to prevent excessive movement. The slat side edge partition 4 is kept from deviating from the track by the partition storage compartment wall panel 5.2 and the partition storage compartment track 5.1. In its plane of motion, it slides along the arc-shaped partition storage compartment track 5.1.

[0068] The partition joint support 4.1 is used to connect the partition joint 4.2 and slides in the wing channel 3.1. It is set at the maximum curvature of the front edge of the wing side edge partition 4. It is a cylinder with a radius of 8-12mm and a height of 15-20mm. There is only one cylinder. It is fixed on the wing side edge partition 4, passes through the wing channel 3.1, and slides in the wing channel 3.1.

[0069] The partition joint 4.2 is used to bear the force of the passive retraction and extension of the slat side edge partition 4. It is set at the top of the partition joint support 4.1, and is spherical in shape with a radius of 15-20mm. There is only one such joint. It is connected to the partition joint support 4.1 by threads and has sliding contact with the curved surface of the slat channel reinforcing frame 3.2.

[0070] The curved protrusion 4.3 of the partition is used for the contact movement between the side edge partition 4 of the wing and the partition storage compartment track 5.1. It is set on the lower rear side of the side edge partition 4, is circular in shape, has a radius of 80-120mm, and is fixed on the side edge partition 4. It contacts the partition storage compartment track 5.1 and slides along the partition storage compartment track 5.1.

[0071] The partition storage compartment track 5.1 is used to guide the movement of the slit side edge partition 4. It is set inside the partition storage compartment 5 and supported by the partition storage compartment wall panel 5.2. It is arc-shaped with a radius of curvature of 600-1000mm and an arc of 50-60°. It is 2-4mm wider than the slit side edge partition 4 and 5-10mm thicker. There is only one track, which is welded between the two partition storage compartment wall panels 5.2 and contacts the curved protrusion 4.3 of the partition.

[0072] The bulkhead storage compartment wall panel 5.2 is used to support the bulkhead storage compartment track 5.1 and to store the slat side edge bulkhead 4, which is located near the wing root at the leading edge of the wing. Its shape depends on the shape of the wing leading edge. It is a rib connecting the upper and lower skins of the wing, and there are 2 of them. It is welded to the bulkhead storage compartment track 5.1 and connected to the wing front spars at the rear. The connection with the skin is made of rivets, and the connection with the wing front spars is made of bolts.

[0073] The bulkhead storage compartment opening 5.3 is used for the entry and exit of the slat side edge bulkhead 4 into the bulkhead storage compartment 5. It is located between the bulkhead storage compartment wall panels 5.2 and is a long strip-shaped skin opening. The upper edge of the opening needs to meet the requirement that it does not interfere with any position of the slat side edge bulkhead 4. This was determined through motion simulation. The width is 1-2mm smaller than the distance between the bulkhead storage compartment wall panels 5.2, and the thickness is the same as the wing skin thickness. There is one opening, which is opened on the wing skin and is an integral structure with the wing skin.

[0074] The working principle of this embodiment is as follows: The leading-edge slat 3 increases lift by changing the camber of the wing's leading edge. During the slat's extension and retraction, the slat side-edge bulkhead 4, guided by the slat channel 3.1 and the bulkhead storage compartment track 5.1, generates relative motion with the leading-edge slat 3. When the slat side-edge is designed to be in the same direction as the airflow, this relative motion prevents the bulkhead storage compartment opening from being too large, thus reducing drag and noise. Furthermore, the bulkhead obstructs the airflow on the inner surface of the leading-edge slat 3, adapting to airflow control requirements at different deflection angles. Wind tunnel test data shows that after adding this bulkhead, the aircraft's stall angle of attack increases by 0.8°, and the maximum lift coefficient increases by 0.05, effectively improving aerodynamic performance.

[0075] The movement of the slat (short for leading-edge slat 3) is generally perpendicular to the leading edge of the wing. Since the slat has a certain spanwise movement after deployment, if the slat side edge is perpendicular to the leading edge of the wing, the plane of the slat side edge after deployment is flush with the retracted position, which is conducive to the arrangement of the bulkhead. However, this side edge has an angle with the incoming airflow after opening, which increases drag. If the slat side edge is parallel to the airflow direction, and the bulkhead is still fixed to the slat side edge, the slat side edge will have a spanwise movement. This would require the spanwise opening of the bulkhead's storage compartment to be very large to meet the requirements of the bulkhead's deployment and retraction. A large opening will increase drag and noise. Therefore, the bulkhead and the slat have mutual movement to both meet the requirements of the slat side edge moving with the airflow and to achieve airflow obstruction. In addition, the opening of the storage compartment is small, which is beneficial to improving the aerodynamic performance of the aircraft.

[0076] By opening the slat channel 3.1 on the lower side skin of the inner surface of the leading edge slat 3 near the wing root, mutual movement between the slat side edge baffle 4 and the leading edge slat 3 is achieved. The baffle does not need to be fixed to the slat side edge. As the leading edge slat 3 is extended or retracted, the slat side edge baffle 4 slides in the slat channel 3.1, maintaining the obstruction of the airflow on the inner surface of the leading edge slat 3. It can adapt to different slat deflection angles. The slat side edge can be designed to reduce drag in the direction of flow, or lift-enhancing methods such as slat root modification can be used, which relaxes the shape design space of the slat and realizes drag reduction and lift enhancement of the slat.

[0077] Based on the above technical solution, the deployment direction of the leading edge slat 3 is forward and downward relative to the leading edge of the wing, with a takeoff positioning angle of 16-22°, a landing positioning angle of 24-30°, and a maximum deflection angle of 25-30°.

[0078] Relative to the leading edge of the wing, the leading edge slat 3 is deployed forward and downward relative to the leading edge of the wing, with a maximum deflection angle of about 25 to 30 degrees. There are generally two types of slats: takeoff and landing. The takeoff slat is generally 16 to 22 degrees (not fully deployed), and the landing slat can reach 24 to 30 degrees (fully deployed).

[0079] Based on the above technical solution, the leading-edge slat 3 is connected to the leading edge of the wing via 2-4 sets of brackets, racks, and gear mechanisms. The brackets are fixed to the leading-edge slat 3 and are used to connect the racks. One end of the rack is fixed to the bracket, and the teeth on the rack mesh with the gear mechanism fixed on the wing. The rotation of the gears drives the movement of the rack, which in turn drives the movement of the leading-edge slat 3 through the brackets. The gear mechanism includes an inner gear and an outer gear. During retraction and extension, an electric actuator drives the inner gear, which transmits torque to the outer gear through a torsion bar. The inner and outer gears synchronously drive the rack to move, realizing the synchronous retraction and extension of the leading-edge slat 3 at different spanwise positions.

[0080] In the prior art, the leading edge slat 3 is generally connected to the leading edge of the wing via 2 to 4 sets of brackets, slide rails, and gear mechanisms. During retraction and extension, an electric actuator drives the inner gear to rotate, and the torque is transmitted to the outer gear through a torsion bar. The two gears rotate simultaneously, driving the rack mounted on the slide rail to move, thus realizing the retraction and extension process. The torsion bar can ensure the consistency of movement of the slide rail and gear mechanism at different positions. Limiting devices are installed at the bottom and end of the slide rail to limit the position. The leading edge slat 3 increases the lift of the wing by increasing the camber of the wing's leading edge, reducing the actual angle of attack of the wing, and delaying the separation of the airflow. The leading edge slat 3 usually deploys in conjunction with the trailing edge flap to jointly improve the lift of the wing.

[0081] Based on the above technical solution, the bottom and end of the leading edge slat 3 rack are provided with limiting devices to limit the retraction and extension positions.

[0082] Based on the above technical solution, the cross section of the slat channel 3.1 is a rounded rectangle with a rounded corner radius of 0.5 times the width.

[0083] Based on the above technical solution, the surface roughness Ra of the slat channel 3.1 is ≤1.6μm.

[0084] Based on the above technical solution, the slat channel reinforcement frame 3.2 is made of stainless steel and must pass a salt spray test of ≥500 hours.

[0085] Based on the above technical solution, the curved surfaces of the slat channel reinforcing frame 3.2 that contact the partition joint support 4.1 and the partition joint 4.2 need to be subjected to hard anodizing treatment with a film thickness of 20-30μm, so that the sliding friction of the slat channel reinforcing frame 3.2 is ≤50N.

[0086] Based on the above technical solution, the slat side edge bulkhead 4 is made of aluminum alloy with a density ≤2.8g / cm³. 3 Yield strength ≥ 300 MPa.

[0087] Based on the above technical solution, a sealing element is arranged on the upper contour of the slat side edge partition 4. The sealing element is connected to the slat side edge partition 4 by an adhesive process to reduce the gap between the slat side edge partition 4 and the leading edge slat 3.

[0088] The sealing material is fluororubber, with a temperature resistance range of -50℃ to 200℃;

[0089] The seal has an elliptical cross-section, and its height is approximately 50%-70% of the partition thickness.

[0090] The seal is installed at the edge of the main wing slot, with a compression amount of 10%-15%. The compression amount can be further adjusted based on experimental verification, depending on specific needs. Existing technologies can be used for experimental verification, which will not be described in detail here.

[0091] Based on the above technical solution, the partition joint support 4.1 is made of 7075-T6 aluminum alloy and the surface is hard anodized with a film thickness of 20-30μm, so that the sliding friction of the partition joint support 4.1 is ≤50N.

[0092] Based on the above technical solution, the partition joint 4.2 is made of 7075-T6 aluminum alloy, with hard chrome plating on the contact surface and a thickness of 5-10μm.

[0093] Based on the above technical solution, the wear test of the partition joint 4.2 must meet the requirement that the wear amount is ≤0.1mm after 2000 cycles of opening and closing.

[0094] Based on the average number of flight passes and flight hours for wide-body passenger aircraft, 10 flight hours correspond to 5 takeoffs and landings, 1000 flight hours correspond to one B-check (500 takeoffs and landings), and 4000 flight hours correspond to one C-check (2000 takeoffs and landings). Therefore, the wear test is set up so that airlines skip the B-check and go directly to the C-check. After 2000 takeoffs and landings, if the wear is ≤0.1mm, it corresponds to one C-check. During the C-check, if the wear is too large, the component can be replaced; it is not necessary to ensure full life cycle matching.

[0095] In addition, the load of slat retraction and extension is mainly borne by the slat retraction and extension mechanism, and the bulkhead joint is hardly used as a load-bearing component, so it is considered that no additional load is required.

[0096] Based on the above technical solution, the curved protrusion 4.3 of the partition is circular with a radius of 80-120mm, and the exposed part accounts for 30%-50%.

[0097] Based on the above technical solution, the minimum gap between the curved protrusion 4.3 of the partition and the track 5.1 of the partition storage compartment is designed to be ≥2mm throughout the entire stroke range of the leading edge slat 3 from 0 to the maximum deflection angle of 30°.

[0098] Based on the above technical solution, the curved protrusion 4.3 of the partition is made of 7075-T6 aluminum alloy, and the contact surface is plated with hard chrome with a thickness of 5-10μm.

[0099] Based on the above technical solution, the wear test of the curved protrusion of the partition 4.3 should meet the requirement that the wear amount is ≤0.1mm after 2000 cycles of opening and closing.

[0100] Based on the above technical solution, the partition storage compartment track 5.1 is made of stainless steel and must pass a salt spray test of ≥500 hours.

[0101] Based on the above technical solution, the partition storage compartment track 5.1 is arc-shaped with a radius of curvature of 600-1000mm, an arc of 50-60°, a width 2-4mm thicker than the side edge partition 4 of the slit, and a thickness of 5-10mm.

[0102] Based on the above technical solution, the partition storage compartment wall panel 5.2 is made of aluminum alloy with a density ≤2.8g / cm³. 3 Yield strength ≥ 300 MPa.

[0103] Based on the above technical solution, the partition storage compartment wall panel 5.2 is connected to the skin by rivets and to the wing front spar by bolts.

[0104] Based on the above technical solution, the minimum safe distance between the upper edge of the partition storage compartment opening 5.3 and all positions of the slatted side edge partition 4 is ≥5mm, and the specific shape is determined through motion simulation.

[0105] Based on the above technical solution, a sealing element is arranged at the junction of the long edge of the slit side edge partition 4 and the partition storage compartment opening 5.3. The sealing element is connected to the slit side edge partition 4 by an adhesive process to reduce the gap between the slit side edge partition 4 and the partition storage compartment wall panel 5.2.

[0106] The sealing material is fluororubber, with a temperature resistance range of -50℃ to 200℃;

[0107] The sealing element has a semi-circular cross-section, and its height is 10%-15% greater than the gap between the partition and the wall panel;

[0108] The seal is installed on the long edge of the 5.3mm opening in the partition storage compartment, with a compression of 10%-15%.

[0109] Based on the above technical solution, the flow improvement device includes the slat deployment stage as described below:

[0110] The leading edge slat 3 initially retracts and fits against the leading edge of the wing, while the slat side edge bulkhead 4 is fully retracted into the bulkhead storage compartment 5. An electric actuator drives the gears to rotate, pushing the leading edge slat 3 outwards and downwards along with the rack. Simultaneously, the slat side edge bulkhead 4 slides downwards within the slat channel reinforcement frame 3.2 via the bulkhead joint support 4.1 and the bulkhead joint 4.2. Due to the three-dimensional shape of the slat channel reinforcement frame 3.2, it tends to move outwards. The curved protrusion 4.3 of the slat side edge bulkhead 4 extends outwards along the bulkhead storage compartment track 5.1 until the leading edge slat 3 reaches its deployed position. The slat side edge bulkhead 4 is flush with and does not extend beyond the side edge of the leading edge slat 3, with its upper contour fitting against the inner surface of the leading edge slat 3, thus achieving airflow obstruction.

[0111] Based on the above technical solution, the flow improvement device includes the slat retraction stage as described below:

[0112] With the leading edge slat 3 in the deployed state, the slat side edge partition 4 is pulled out of the partition storage compartment 5 to close the side edge recess. The electric actuator drives the gear to rotate in the opposite direction, and the leading edge slat 3 retracts inward and upward along with the rack. The slat side edge partition 4 slides upward within the slat channel reinforcement frame 3.2 through the partition joint support 4.1 and the partition joint 4.2. Due to the three-dimensional shape of the slat channel reinforcement frame 3.2, it tends to move inward. The curved protrusion 4.3 of the partition retracts inward along the partition storage compartment track 5.1, and is finally completely stored in the partition storage compartment 5. The leading edge slat 3 fits against the leading edge of the wing, completing the retraction.

[0113] Based on the above technical solutions, the following alternative solutions are also included:

[0114] The transmission between the slatted side edge partition 4 and the partition storage compartment 5 can adopt a gear-rack structure: replace the curved protrusion 4.3 of the partition with... Figure 7The partition gear 4.4 shown is replaced with a rack and pinion track 5.1. The gear and rack meshing clearance is 0.1-0.2mm (module 2-3mm, number of teeth 12-20). Due to the sweep angle of the wing leading edge, the gear adopts helical teeth (axial direction perpendicular to the partition plate surface). The helical rack is fixed to the inner wall of the partition storage compartment on the inner side of the main wing. The gear shaft is fixed to the partition with bolts. Limiting blocks are set at both ends of the rack to prevent disengagement. The meshing area is covered with a dust cover.

[0115] Based on the above technical solution, the assembly method of the flow improvement device is as follows:

[0116] A slot 3.1 is opened on the lower side skin of the concave cavity inside the leading edge slat 3 near the wing root, ensuring that the length meets the movement stroke of the slat side edge partition 4 (the sliding distance of the support column is ≥100mm when fully deployed), the width is 1-2mm larger than the diameter of the support column 4.1 of the partition joint, the cross section is machined into a rounded rectangle (the radius of the rounded corner is 0.5 times the width), and the surface roughness is controlled at Ra≤1.6μm;

[0117] Install slat channel reinforcing frames 3.2 on both the inner and outer sides of the slat channel 3.1, and connect them through bolt holes. The holes of the reinforcing frames are consistent with the shape of the channel 3.1. The dimensions are processed by increasing the length by 20-30mm, the width by 20-30mm, and the thickness by 10-15mm. The material is stainless steel and hard anodized (film thickness 20-30μm).

[0118] After threading the partition joint support 4.1 and the partition joint 4.2, install it at the point of maximum curvature at the leading edge of the slat side partition 4. The spherical surface of the partition joint 4.2 is plated with hard chrome (thickness 5-10μm). The partition side partition 4 slides in contact with the leading edge slat 3 through the partition joint support 4.1 and the partition joint 4.2, ensuring that the partition joint support 4.1 passes through the slat channel 3.1.

[0119] The welded bulkhead storage compartment track 5.1 is located between two bulkhead storage compartment wall panels 5.2. The track is arc-shaped (radius of curvature 600-1000mm, arc 50-60°), and its width is 2-4mm thicker than the slat side edge bulkhead 4. The material is stainless steel. The bulkhead storage compartment wall panel 5.2 is riveted to the upper and lower wing skins and bolted to the front spar. It is 5-10mm thick and made of aluminum alloy.

[0120] The partition storage compartment has an opening of 5.3mm. Ensure that the minimum safe distance between the upper edge of the opening and all positions of the slat side edge partition 4 is ≥5mm (determined through motion simulation). Finally, install a fluororubber seal (elliptical cross section, height of 50%-70% of the partition thickness, and compression of 10%-15%) on the upper contour of the slat side edge partition 4.

[0121] In this embodiment, the leading edge slat 3 is retractably connected to the leading edge of the wing via a bracket, rack, and gear mechanism. The slat channel 3.1 is opened at a specific position on the leading edge slat 3, and slat channel reinforcing frames 3.2 are installed on its inner and outer sides. The slat side edge partition 4 slides in contact with the leading edge slat 3 via partition joint support 4.1 and partition joint 4.2. The partition joint support 4.1 passes through the slat channel 3.1, and the partition curved protrusion 4.3 contacts the partition storage compartment track 5.1. The partition storage compartment track 5.1 is welded between the partition storage compartment wall panels 5.2. The wall panels 5.2 are connected to the wing skin and front spars. The partition storage compartment opening 5.3 is opened at a specific position on the partition storage compartment 5. All components form a complete motion guidance and airflow blocking structure through bolts, rivets, and other connecting parts.

[0122] The leading edge slat 3 and the partition 4 achieve relative movement through the "channel-support" sliding pair: when the side edge of the slat is designed in the direction of the flow, the partition does not need to be fixed to the slat. Its movement trajectory is jointly limited by the channel 3.1 and the partition storage compartment track 5.1, which avoids the partition storage compartment opening being too large, reduces resistance and noise, and at the same time, the upper surface seal of the partition prevents the airflow separation on the root side of the slat.

[0123] Based on the above technical solution, in order to verify the technical effect of the leading-edge slat root side-edge bulkhead of the aircraft, the flow improvement device was tested in a low-speed wind tunnel test of a wide-body passenger aircraft. The specific test verification method is as follows:

[0124] The wind tunnel test was conducted in a low-speed pressurized closed-loop continuous wind tunnel. The test section of the wind tunnel measured 4.5m × 3.5m. The operating pressure of the wind tunnel was atmospheric pressure to 0.4MPa. The maximum wind speed at atmospheric pressure was 130m / s, and the maximum wind speed at 0.4MPa was 90m / s. The maximum Reynolds number was 8.5 × 10⁻⁶. 6 .

[0125] The test model has a scale of approximately 4%, and its configuration is a takeoff stand (with slats not fully deployed). It is made of aluminum alloy and stainless steel, with the stainless steel surface treated for rust prevention. The model is tested using a single strut for support. During the test, the model is connected to a balance, which is connected to the angle of attack and sideslip angle control mechanisms via the strut. The model's attitude is controlled by the angle of attack, sideslip angle mechanisms, and attitude angle control system, which can achieve continuous or stepped attitude changes.

[0126] The maximum angle of attack for the model test ranged from -14° to 32°, the test wind speed was 68 m / s, the wind tunnel test pressure was 0.4 MPa, the air temperature was 20°C, and data was collected every 0.25°, collecting test data for an angle of attack range from -5° to 27°.

[0127] The test results are as follows Figure 10As shown, after adding the leading-edge slat root side-edge slats, the aircraft's stall angle of attack increased by 0.8°, and the maximum lift coefficient increased by 0.05. Wind tunnel tests demonstrated repeatability, and the effect of the slat side-edge slats on the aircraft's maximum lift coefficient far exceeded the repeatability error, indicating reliable results.

[0128] The following is a specific embodiment.

[0129] A slat channel 3.1 is provided on the lower side skin of the concave inner surface of the leading edge slat 3 near the wing root. The slat channel 3.1 is a long strip-shaped skin opening. Its length must meet the movement stroke of the slat side edge partition 4 (the sliding distance of the support column when the leading edge slat 3 is fully deployed is ≥100mm). Its width is 1-2mm larger than the diameter of the support column 4.1 of the partition joint of the slat side edge partition 4. Its thickness is the thickness of the slat skin (1-2mm). The cross-section is a rounded rectangle (the radius of the rounded corner is 0.5 times the width). (5 times), slat channel 3.1 has reinforcing frames 3.2 installed on both the inner and outer sides of the inner surface skin of the slat cavity, to strengthen the nearby skin to withstand tensile and compressive loads. These frames are connected via bolt holes. The holes in the reinforcing frames 3.2 are identical in shape to those in the slat channel 3.1. Compared to the slat channel 3.1, the reinforcing frames 3.2 need to be 20-30mm longer, 20-30mm wider, and 10-15mm thicker. The inner surface of the slat channel 3.1 is smooth, guiding the sliding movement of the partition joint support 4.1 and the partition joint 4.2, ensuring smooth deployment and retraction of the slat side edge partition 4. The rounded holes at both ends of the reinforcing frames 3.2 restrict the movement of the partition joint support 4.1 and the partition joint 4.2, preventing them from detaching from the slat channel 3.1. The shape and size of the diaphragm joint support 4.1 and the diaphragm joint 4.2 are adapted to the slat channel 3.1 to ensure stable sliding within the channel, while allowing a certain degree of lateral freedom to accommodate the deformation and movement of the slat.

[0130] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

[0131] The above description is only a preferred embodiment of the present utility model. The protection scope of the present utility model is not limited to the above embodiments. Any equivalent modifications or changes made by those skilled in the art based on the content disclosed in the present utility model should be included in the protection scope recorded in the claims.

Claims

1. A flow improvement device at the root side of a leading-edge slat, characterized in that, include: The leading edge slat (3) is retractable and extendable to the leading edge of the wing via a bracket, rack, and gear mechanism; The slat channel (3.1) is opened on the lower side skin of the concave surface of the leading edge slat (3) near the root of the wing, and its width is 1-2 mm larger than the diameter of the diaphragm joint support (4.1). The slat side edge slat (4) passes through the slat channel (3.1) via the slat joint support (4.1); The partition storage compartment track (5.1) is welded and fixed between two partition storage compartment wall panels (5.2), and its width is 2-4mm larger than the thickness of the slit side edge partition (4); The curved protrusion (4.3) of the partition is fixed to the lower rear side of the partition (4) on the side edge of the slit and slides in contact with the partition storage compartment track (5.1); A seal is provided on the upper contour of the slat side edge partition (4) and the edge of the partition storage compartment opening (5.3).

2. The flow improvement device at the root side of a leading-edge slat as described in claim 1, characterized in that, The slat channel (3.1) is equipped with slat channel reinforcement frames (3.2) on both the inner and outer sides. The reinforcement frames are connected to the skin near the slat channel (3.1) by bolts.

3. The flow improvement device at the root side of a leading-edge slat as described in claim 1, characterized in that, The rear part of the partition storage compartment wall panel (5.2) is bolted to the front wing beam and riveted to the upper and lower wing skins.

4. The flow improvement device at the root side of a leading-edge slat as described in claim 1, characterized in that, The partition joint (4.2) is connected to the partition joint support (4.1) by threads, and the spherical surface of the partition joint (4.2) slides in contact with the curved surface of the slat channel reinforcing frame (3.2).

5. The flow improvement device at the root side of a leading-edge slat as described in claim 1, characterized in that, The slat side edge partition (4) slides along the arc-shaped path of the partition storage compartment track (5.1) via the partition curved protrusion (4.3).

6. The flow improvement device at the root side of a leading-edge slat as described in claim 1, characterized in that, The opening (5.3) of the partition storage compartment is made on the wing skin, and the minimum safe distance between the upper edge of the opening and all positions of the slat side edge partition (4) is ≥5mm.

7. The flow improvement device at the root side of a leading-edge slat as described in claim 1, characterized in that, Fluororubber seals are installed on the upper contour of the slat side edge partition (4) to seal the gap between the partition and the inner surface of the leading edge slat (3).

8. The flow improvement device at the root side of a leading-edge slat as described in claim 1, characterized in that, A gear-rack structure is used to replace the curved protrusions of the partition (4.3) and the partition storage compartment track (5.1); The gear is fixed to the side edge partition (4) of the slat, and the rack is fixed to the inner wall of the partition storage compartment wall (5.2); The gear is helical and its axis is perpendicular to the surface of the partition plate. Limiting blocks are provided at both ends of the rack, and the meshing area is covered with a dust cover.

9. The flow improvement device at the root side of a leading-edge slat as described in claim 1, characterized in that, The sealing element is made of fluororubber and has a temperature resistance range of -50℃ to 200℃. Its cross-section is elliptical, and its height is 50%-70% of the thickness of the slat side edge partition (4); The compression amount installed at the edge of the main wing slot is 10%-15%.

10. The flow improvement device at the root side of a leading-edge slat as described in claim 1, characterized in that, The partition joint (4.2) is a spherical structure with a radius of 15-20mm; The curved protrusions (4.3) on the partition are circular protrusions with a radius of 80-120mm.

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