An air vent structure for improving the aerodynamic performance of an airfoil

Abstract

This invention discloses a ventilation structure for improving the aerodynamic performance of an aircraft wing, belonging to the field of aircraft design technology. The aircraft wing includes a leading-edge slat, a wing body, and flaps. The key feature is that a front vent and a rear vent are respectively provided at the leading and trailing edges of the wing body. The leading-edge slat can block the front vent after retraction and reset. The aircraft is equipped with positive and negative pressure air sources, and the front and rear vents are each connected to two positive and negative pressure air vents of the positive and negative pressure air sources. This invention effectively optimizes the aerodynamic characteristics of the wing, significantly improves the overall flight performance and operational economy, and fully utilizes the structural characteristics of the original flaps and slats of civil aircraft. During cruise and ground taxiing, when the slats are retracted, the repositioned leading-edge slat completely blocks the front vent, forming a natural protective structure and preventing clogging of the front vent.

Description

Technical Field

[0001] This invention relates to the field of aircraft design technology, and in particular to a ventilation structure for improving the aerodynamic performance of an airfoil. Background Technology

[0002] The aerodynamic performance of an aircraft wing is a core factor that determines the aircraft's flight efficiency, range, and operational economy. However, issues such as airflow separation on the wing surface, leading-edge vortex breakage, poor stall characteristics, and high flight drag have always been key technical bottlenecks that restrict the improvement of the aerodynamic performance of fixed-wing aircraft.

[0003] Active flow control technology, as an effective means to improve wing aerodynamic characteristics and optimize flight performance, has become a key research direction in the field of aerodynamics due to its advantages such as strong controllability and significant performance improvement. Current mainstream research proposes combined flow control schemes based on blow-in / blow-out and blow-in / blow-out methods. This involves adding air grid devices at the fore and aft positions of the wing and optimizing wing surface flow characteristics through active airflow regulation. This type of technology can effectively enhance the intensity of leading-edge vortices and surface negative pressure, delay the phenomenon of leading-edge vortex breakup, effectively increase the lift coefficient in the post-stall phase of the wing, suppress the sudden drop in lift and pitching moment, and significantly expand the effective flight envelope of the aircraft. However, currently available wing air grid flow control technologies and related research results have many significant defects and technical shortcomings in terms of practical engineering applications, adaptability to civil scenarios, structural practicality, and operational condition compatibility, making it difficult to meet the needs of large-scale, practical applications in the civil aviation field. Specific problems are as follows: First, existing core research focuses primarily on aircraft with special flying wing configurations, which have limited application scenarios and low general value. The flight control systems of such aircraft are complex, have high R&D costs, and slow technological iteration, resulting in low overall operational economics. Consequently, the research results are only suitable for niche scenarios and cannot be widely applied to ordinary fixed-wing civil aircraft with a wider range of applications. This leads to high barriers to technology implementation and limited promotional value.

[0004] Secondly, existing technology research focuses on a single operating condition, detached from the actual operational conditions of civil aircraft. Current related solutions only conduct design and experimental research on the smooth-configuration wing of the entire aircraft, without considering the operating conditions of the flaps and slats, the core components of civil passenger and cargo aircraft. During flight, civil aircraft flaps and slats frequently open to adapt to conditions such as takeoff and landing, and low-speed flight. However, the existing air gate device design does not take into account the structural compatibility and operational feasibility of the flaps and slats in the open state, resulting in serious conflicts with the conventional structural operating conditions of civil aircraft.

[0005] Furthermore, existing devices suffer from poor operational reliability and inherent operational risks. Existing air grid flow control devices need to operate continuously throughout the entire flight. Once the aircraft stops, air grid blockage is likely to occur, which can easily lead to safety hazards such as wing surface airflow control failure and sudden changes in aerodynamic performance. They cannot meet the requirements of multi-condition, high reliability, and continuous stable operation of civil aircraft.

[0006] Finally, the existing technology has a complex structural design and is extremely difficult to implement in engineering. The lack of optimization design in conjunction with the original wing structure makes overall aircraft modification very difficult. Furthermore, civil passenger and cargo aircraft are characterized by stringent airworthiness certification standards, long technology iteration cycles, high modification costs, and high sensitivity to overall aircraft performance. Existing technology design concepts are too advanced, have poor adaptability, and have extremely low practical value in the short term, making large-scale engineering applications impossible.

[0007] Therefore, how to provide a ventilation structure that improves the aerodynamic performance of an airfoil and overcomes the above-mentioned problems is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0008] To achieve the above objectives, the present invention provides a ventilation structure for improving the aerodynamic performance of an aircraft wing. The aircraft wing includes a leading-edge slat, a wing body, and flaps. A front vent and a rear vent are respectively provided at the leading and trailing edges of the wing body. The leading-edge slat can block the front vent after retracting and resetting. The aircraft is provided with a positive and negative pressure air source, and the front vent and the rear vent are respectively connected to the two positive and negative pressure air vents of the positive and negative pressure air source.

[0009] Preferably, both the front vent and the rear vent are located on the upper surface of the wing body.

[0010] Preferably, both the front vent and the rear vent are provided in multiples, with the multiple front vents arranged sequentially along the length direction of the wing body and the multiple rear vents arranged sequentially along the length direction of the wing body.

[0011] Preferably, the tangent direction of the upper surface of the wing body at the front vent is the same as the ventilation direction of the front vent; the tangent direction of the upper surface of the wing body at the rear vent is the same as the ventilation direction of the rear vent.

[0012] Preferably, the positive and negative pressure air source includes an air pump, a three-position four-way reversing valve, valve one, valve two, valve three, valve four, valve five, valve six, valve seven, and the aircraft's bleed air system; the air pump has an inlet end and an outlet end; the first end of valve one, the first working air inlet of the three-position four-way reversing valve, and the first end of valve four are all connected to the front vent air passage; the second end of valve one, the second working air inlet of the three-position four-way reversing valve, the first end of valve two, and the first end of valve seven are all connected to the rear... The vent is connected to the air passage; the second end of valve four and the first end of valve five are both connected to the air inlet of the air pump; the first end of valve six, the second end of valve seven, and the first end of valve three are all connected to the air outlet of the air pump; the second end of valve five and the second end of valve six are each connected to the air inlet and exhaust port of the three-position four-way reversing valve; the second end of valve two is connected to the air outlet of the induced draft system; the second end of valve three is connected to the air inlet of the induced draft system.

[0013] Preferably, both the front vent and the rear vent are covered with a perforated plate.

[0014] The advantages and positive effects of the ventilation structure for improving the aerodynamic performance of an airfoil described in this invention are as follows: 1. This invention effectively optimizes the aerodynamic characteristics of the wing, significantly improving the overall flight performance and operational economy. Based on the leading and trailing edges of the wing body, and combined with a positive and negative pressure air source system consisting of an air pump, a three-position four-way reversing valve, and multiple valves, this invention can flexibly achieve four controllable operating modes: dual-hole blowing, dual-hole suction, front suction followed by rear blowing, and front blowing followed by rear suction. Based on the principle of active blowing and suction control, it can effectively intervene in the airflow state of the wing surface, delay boundary layer airflow separation, enhance the leading-edge vortex intensity and negative pressure on the wing surface, suppress leading-edge vortex breakup, effectively improve wing stall characteristics, avoid the problem of sudden drop in lift and pitching moment after stall, significantly improve the wing's lift coefficient and lift-to-drag ratio, and reduce flight drag.

[0015] 2. This invention positions the front vent behind the leading-edge slat, fully utilizing the structural characteristics of the original flaps and slats of civil aircraft. During cruise and taxiing, when the slats retract, the repositioned leading-edge slats completely block the front vent, forming a natural protective structure that effectively prevents sand, water vapor, and foreign objects from entering the vent and internal air passage system. This design requires no additional protective components, relying on the aircraft's existing structure for passive protection, ensuring the continuous and stable operation of the flow control device across all flight conditions.

[0016] 3. This invention is tailored to the core operational characteristics of civil passenger and cargo aircraft, matching the real-world working scenarios of frequent flap and slat opening and closing. During takeoff, landing, and low-speed flight with flaps and slats open, the ventilation structure can perform normal blowing and sucking control operations without being affected by the flaps and slats' operational status, demonstrating extremely strong structural compatibility and adaptability to operating conditions. Furthermore, the ventilation holes are evenly distributed along the length of the wing, and the ventilation direction matches the tangential direction of the wing's upper surface, conforming to the airflow pattern of the wing surface and resulting in higher aerodynamic control precision.

[0017] 4. This invention deeply couples the air pump with the aircraft's native bleed air system. In the intake mode, the air drawn from the wing surface can be delivered to the aircraft's bleed air system to provide an air source for other air-using equipment on board, realizing the recycling and reuse of airflow resources and avoiding energy waste. Attached Figure Description

[0018] Figure 1 This is a schematic diagram showing the arrangement of the front and rear vents in this invention. Figure 2 This is a schematic diagram of the principle when both the front and rear vents of the present invention are blowing air outwards. Figure 3 This is a schematic diagram of the principle when both the front and rear vents of the present invention are drawing in air. Figure 4 This is a schematic diagram illustrating the principle of air intake through the front vent and air blowing through the rear vent of the present invention. Figure 5 This is a schematic diagram illustrating the principle of the invention when the front vent blows air and the rear vent draws air.

[0019] Figure Labels 1. Leading edge slats; 2. Wing body; 3. Flaps; 4. Front vent; 5. Rear vent; 6. Air pump; 7. Three-position four-way reversing valve; 8. Valve 1; 9. Valve 2; 10. Valve 3; 11. Valve 4; 12. Valve 5; 13. Valve 6; 14. Valve 7; 15. Bleed air system. Detailed Implementation

[0020] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0021] In this application, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. In case of any inconsistency, the meaning set forth in this specification or derived from the content described herein shall prevail. Furthermore, the terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit the scope of this application.

[0022] See appendix Figure 1-5 This is a schematic diagram of the overall and partial structure of one embodiment of the present invention. Specifically, the present invention discloses a ventilation structure for improving the aerodynamic performance of an aircraft wing. The aircraft wing includes a leading-edge slat 1, a wing body 2, and flaps 3. A front vent 4 and a rear vent 5 are respectively provided on the leading and trailing edges of the wing body 2. Both the front and rear vents 4 and 5 are located on the upper surface of the wing body 2. Multiple front and rear vents 4 and 5 are provided, arranged equidistantly along the length of the wing body 2. The front vents 4 are located near the leading-edge slat 1, and the rear vents 5 are located near the flaps 3. When the leading-edge slat 1 retracts and resets, it can block the front vents 4, thereby protecting the front vents 4 and preventing blockage.

[0023] The aircraft is equipped with positive and negative pressure air sources. The front vent 4 and the rear vent 5 are each connected to the two positive and negative pressure air vents of the positive and negative pressure air sources.

[0024] The tangent direction of the upper surface of the wing body 2 at the front vent 4 is the same as the ventilation direction of the front vent 4. The tangent direction of the upper surface of the wing body 2 at the rear vent 5 is the same as the ventilation direction of the rear vent 5.

[0025] In this application, the positive and negative pressure air sources include an air pump 6, a three-position four-way reversing valve 7, valve one 8, valve two 9, valve three 10, valve four 11, valve five 12, valve six 13, valve seven 14, and the aircraft's bleed air system 15. The aircraft's control system can control the operation of the air pump 6, the three-position four-way reversing valve 7, valve one 8, valve two 9, valve three 10, valve four 11, valve five 12, valve six 13, valve seven 14, and the bleed air system 15. The air pump 6 has an inlet end and an outlet end. In this embodiment, the air pump 6 is fixed inside the corresponding wing body 2. The first end of valve one 8, the first working air inlet of the three-position four-way reversing valve 7, and the first end of valve four 11 are all connected to the air passage of the front vent 4. The second end of valve one 8, the second working air inlet of the three-position four-way reversing valve 7, the first end of valve two 9, and the first end of valve seven 14 are all connected to the air passage of the rear vent 5. The second end of valve 4 (11) and the first end of valve 5 (12) are both connected to the air inlet of air pump 6. The first end of valve 6 (13), the second end of valve 7 (14), and the first end of valve 3 (10) are all connected to the air outlet of air pump 6. The second end of valve 5 (12) and the second end of valve 6 (13) are respectively connected to the air inlet and outlet of three-position four-way directional valve 7. The second end of valve 2 (9) is connected to the air outlet of bleed air system 15. The second end of valve 3 (10) is connected to the air inlet of bleed air system 15.

[0026] Both the front vent 4 and the rear vent 5 are covered with a perforated plate (not shown in the figure). The perforated plate can intercept large particles and prevent them from clogging the front vent 4 and the rear vent 5.

[0027] The ventilation structure of this application has four operating modes: First, both the front vent 4 and the rear vent 5 are blowing air outwards. At this time, valves 3 10, 4 11, 5 12, 6 13 and 7 14 are in the closed state, valves 1 8 and 2 9 are in the open state, the valve core of the three-position four-way reversing valve 7 is in the neutral position, and the bleed air system 15 on the aircraft can pump gas to both the front vent 4 and the rear vent 5 at the same time.

[0028] Second, both the front vent 4 and the rear vent 5 are drawing in air. At this time, valves 2 (9), 5 (12), 6 (13), and 7 (14) are all in the closed state, while valves 1 (8), 3 (10), and 4 (11) are in the open state. The valve core of the three-position four-way reversing valve 7 is in the neutral position. The air inlet of the air pump 6 is connected to both the front vent 4 and the rear vent 5, and the air outlet of the air pump 6 is connected to the bleed air system 15 on the aircraft. That is, the air pump 6 draws air from the front vent 4 and the rear vent 5 and then delivers it to the bleed air system 15 for use by other air-consuming equipment on the aircraft.

[0029] Third, the front vent 4 draws in air and the rear vent 5 blows air. Valves 1 (8), 2 (9), 3 (10), 4 (11), and 7 (14) are all in the closed state. Valves 5 (12) and 6 (13) are in the open state. The valve core of the three-position four-way reversing valve 7 is in the left position. The air inlet of the air pump 6 is connected to the front vent 4, and the air outlet of the air pump 6 is connected to the rear vent 5.

[0030] Fourth, the front vent 4 blows air and the rear vent 5 draws air. Valves 1, 8, 2, 9, 3, 10, 4, 11 and 7, 14 are all in the closed state. Valves 5, 12 and 6, 13 are in the open state. The valve core of the three-position four-way reversing valve 7 is in the right position. The air outlet of the air pump 6 is connected to the front vent 4 and the air inlet of the air pump 6 is connected to the rear vent 5.

[0031] With the leading edge slat 1 open, the blowing and sucking action of the front vent 4 and the rear vent 5 can improve performance parameters such as wing efficiency, lift-to-drag ratio and stall. Depending on the real-time flight status of the aircraft, one of the above four working modes can be selected to reduce wing drag.

[0032] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A ventilation structure for improving the aerodynamic performance of an aircraft wing, the wing comprising a leading-edge slat, a wing body, and flaps, characterized in that, A front vent and a rear vent are respectively provided on the leading edge and trailing edge of the wing body. The leading edge slat can block the front vent after retracting and resetting. The aircraft is equipped with a positive and negative pressure air source. The front vent and the rear vent are respectively connected to the two positive and negative pressure air vents of the positive and negative pressure air source.

2. The ventilation structure for improving the aerodynamic performance of an airfoil according to claim 1, characterized in that, Both the front vent and the rear vent are located on the upper surface of the wing body.

3. The ventilation structure for improving the aerodynamic performance of an airfoil according to claim 1, characterized in that, Both the front vent and the rear vent are provided in multiples, with the multiple front vents arranged sequentially along the length direction of the wing body and the multiple rear vents arranged sequentially along the length direction of the wing body.

4. The ventilation structure for improving the aerodynamic performance of an airfoil according to claim 1, characterized in that, The tangent direction of the upper surface of the wing body at the front vent is the same as the ventilation direction of the front vent; the tangent direction of the upper surface of the wing body at the rear vent is the same as the ventilation direction of the rear vent.

5. The ventilation structure for improving the aerodynamic performance of an airfoil according to claim 1, characterized in that, The positive and negative pressure air source includes an air pump, a three-position four-way reversing valve, valve one, valve two, valve three, valve four, valve five, valve six, valve seven, and the aircraft's bleed air system; the air pump has an inlet end and an outlet end; the first end of valve one, the first working air inlet of the three-position four-way reversing valve, and the first end of valve four are all connected to the front vent air passage; the second end of valve one, the second working air inlet of the three-position four-way reversing valve, the first end of valve two, and the first end of valve seven are all connected to the rear vent air passage. The air passage is connected; the second end of valve four and the first end of valve five are both connected to the air inlet of the air pump; the first end of valve six, the second end of valve seven, and the first end of valve three are all connected to the air outlet of the air pump; the second end of valve five and the second end of valve six are each connected to the air inlet and exhaust port of the three-position four-way reversing valve; the second end of valve two is connected to the air outlet of the induced draft system; the second end of valve three is connected to the air inlet of the induced draft system.

6. The ventilation structure for improving the aerodynamic performance of an airfoil according to claim 1, characterized in that, Both the front vent and the rear vent are covered with a perforated plate.

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