Foreign matter removing device of bifurcated air inlet channel with adjustable flow guide mechanism and bifurcated air inlet channel
The forked air inlet foreign object removal device with an adjustable guide mechanism dynamically adjusts the guide plate position and airflow distribution, solving the problem of foreign object entry and improving flight safety and engine performance.
Patent Information
- Application Number
- CN202511080805.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-04
- Publication Date
- 2025-09-16
AI Technical Summary
The existing bifurcated air inlet has insufficient protection against foreign object threats and cannot effectively prevent foreign objects from entering. In addition, the airflow is improperly distributed under normal flight conditions, resulting in a decrease in flow field quality and loss of aerodynamic performance.
The forked air inlet foreign object removal device adopts an adjustable guide mechanism. Through the cooperation of the guide plate and the drive device, it dynamically adjusts the airflow distribution and the position of the guide plate to prevent foreign objects from entering the engine flow path and optimize the airflow distribution under normal flight conditions.
It effectively prevents foreign matter from entering the engine, improves flight safety, reduces aerodynamic losses under normal flight conditions, and improves the aerodynamic performance and overall safety of the engine flow path.
Smart Images
Figure CN120650042A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to an aero-engine air intake duct, and in particular to a forked air intake duct foreign matter removal device with an adjustable flow guide mechanism and the forked air intake duct. Background Art
[0002] During flight, aircraft often face a variety of complex and challenging environments. For example, aircraft may encounter hail while flying through clouds, flocks of birds during takeoff and landing, and even ingest sand and gravel during dust storms or when taking off and landing on specific runways such as concrete, grass, or snow. These situations can expose the aircraft's air intake to the risk of foreign matter intrusion. Once foreign matter is swallowed by the air intake, it can have serious consequences for the engine and even the entire aircraft. This is mainly reflected in the following aspects:
[0003] Degraded flow field quality: Mixing of inlet airflow with foreign matter can lead to a degraded flow field quality. Larger foreign matter can severely obstruct the intake duct, causing significant fluctuations in the total pressure recovery coefficient and total pressure distortion, thus affecting engine stability and performance.
[0004] Component damage: When foreign objects hit the wall of the main engine air inlet, it may cause damage such as pits, cracks, and holes on the wall, thereby significantly reducing the aerodynamic performance of the propeller and air inlet and the safety of the aircraft structure.
[0005] Engine failure: More seriously, if these foreign objects are sucked into the engine and collide with the high-speed rotating blades, they can damage the blade structure or even cause it to fall off. At the very least, this can reduce engine propulsion efficiency and shorten its service life; at worst, it can cause the engine to surge or stall, endangering flight safety.
[0006] Therefore, to ensure flight safety and extend engine life, an inlet protection system that can effectively remove foreign objects is needed. Existing bifurcated inlets have certain design limitations: First, the excessively large flow area at the bifurcation makes it difficult to fully utilize their protective function against foreign object threats, effectively preventing them from entering the inlet, thereby reducing inlet safety. Second, under normal flight conditions, the lack of effective diversion measures causes a large amount of airflow to unnecessarily flow into the foreign object removal flow path, reducing airflow into the engine flow path and increasing aerodynamic losses. This not only reduces the aerodynamic performance of the inlet, but also weakens the efficiency of the air intake it provides to the engine. Summary of the Invention
[0007] Purpose of the Invention: To address the above shortcomings, the present invention provides a safe, forked air intake foreign object removal device with an adjustable flow guide mechanism that improves engine aerodynamic performance. Suitable for a variety of aircraft requiring foreign object removal, the device aims to enhance the safety and reliability of the air intake in complex flight environments and extend engine life.
[0008] The present invention also provides a bifurcated air intake duct using the above-mentioned foreign matter removal device.
[0009] Technical solution: In order to solve the above problems, the present invention adopts a forked air inlet foreign object removal device with an adjustable guide mechanism, including a guide plate and a driving device arranged in the forked air inlet inlet, and guide grooves are provided on both sides of the forked air inlet inlet. The two ends of the guide plate extend out of the guide grooves on both sides of the forked air inlet inlet and are connected to the driving device. The driving device drives the guide plate to move along the guide groove of the forked air inlet, thereby realizing the switching of guiding the airflow at the forked air inlet inlet to the two forked flow channels of the forked air inlet.
[0010] Furthermore, the driving device includes a screw motor, a rocker arm, a slider and a guide rail. The two ends of the guide plate extend out of the guide grooves on both sides of the forked air inlet inlet and are fixedly connected to one end of the rocker arm. The other end of the rocker arm is hinged to the slider. The screw motor drives the slider to move along the guide rail, and the extension direction of the guide rail is parallel to the extension direction of the guide groove.
[0011] Furthermore, the driving device also includes a guide plate fixedly connected to the outer wall of the forked air inlet duct, and the guide plate is provided with a limit groove. Both ends of the guide plate extend out of the guide grooves on both sides of the forked air inlet inlet respectively, and are fixedly connected to one end of the rocker arm after passing through the limit groove. The range of movement provided by the limit groove is within the range of movement provided by the guide groove. The guide plate is located at one end point of the limit groove to form a first guide angle, and the slider drives the guide plate to move toward the other end of the limit groove through the rocker arm. When the guide plate reaches the other end point of the limit groove at the first guide angle, the slider continues to move. Under the limitation of the limit groove, the rocker arm rotates relative to the slider, and the guide plate forms a second guide angle. When the guide plate returns to the other end point of the limit groove at the second guide angle, the slider continues to move. Under the limitation of the limit groove, the rocker arm rotates relative to the slider, and the guide plate restores the first guide angle.
[0012] Furthermore, the guide plate includes a main body and a connecting part. The method for determining the cross-sectional shape of the main body of the guide plate is: taking the cross-sectional shape of the NACA airfoil as the basic profile, stretching the basic profile n times along the chord direction to obtain a stretched profile, and synchronously deflecting the two ends of the stretched profile toward the inward concave side. The connecting part is a cylinder extending outward from the two ends of the main body, and the cylinder is fixedly connected to the rocker arm through the guide groove and the limit groove.
[0013] Furthermore, the calculation relationship between the movement distance of the guide plate, the movement distance of the slider and the rotation angle of the guide plate is:
[0014]
[0015] Where α is the acute angle between the rocker arm and the guide rail when at one end of the guide slot, β is the acute angle between the rocker arm and the guide rail when at the other end of the guide slot. The difference between α and β is the rotation angle required to control the deflector plate. l1 is the travel distance of the slider, l2 is the travel distance of the deflector plate, r is the effective radius of the rocker arm during rotation, l3 is a diagonal line of the quadrilateral formed by the travel distances of the deflector plate and the slider, and θ is the acute angle between the diagonal line and the extension direction of the guide rail. The distance between the hinge point between the rocker arm and the slider and the guide slot is less than the effective radius of the rocker arm during rotation.
[0016] The present invention also adopts a forked air intake duct using the above-mentioned forked air intake duct foreign object removal device, the forked air intake duct includes an upwardly forked engine flow duct and a downwardly forked foreign object removal flow duct, the guide grooves on both sides of the forked air intake duct inlet and the limit grooves on the guide plate extend up and down, when the guide plate is located at the lower end of the guide plate limit groove, the first angle range between the chord of the guide plate and the horizontal direction is 5°~10°; when the guide plate is located at the upper end of the guide plate limit groove, the chord of the guide plate rotates 10° counterclockwise relative to the first angle; when the guide plate is located at the upper end of the guide plate limit groove, foreign objects are prevented from entering the engine flow duct; when the guide plate is located at the lower end of the guide plate limit groove, the airflow distribution is adjusted to reduce the airflow flowing into the foreign object removal flow duct.
[0017] Furthermore, a bulge is provided on the upper wall surface of the forked air inlet inlet, and the bulge is located upstream of the guide plate. When the guide plate is located at the uppermost end of the guide plate limiting groove, it cooperates with the bulge surface to prevent foreign matter from entering the engine flow channel.
[0018] Furthermore, a boundary layer suction slit is provided downstream of the bulge. When the guide plate is located at the uppermost end of the guide plate limit slot, the suction slit is used to promptly discharge low-energy flow formed by the guide plate's obstruction. A venting cavity is provided outside the bifurcated air inlet to accommodate the low-energy flow discharged from the suction slit.
[0019] Beneficial effects: Compared with the prior art, the significant advantage of the present invention is that the forked air inlet can dynamically adjust its working state according to the flight environment (such as flying through clouds, sandstorms, taking off and landing on different runways, etc.) through the adjustable deflector, effectively responding to the challenges of complex flight conditions of the aircraft. When facing threats from foreign objects such as hail, sand, and flocks of birds, the position and posture of the deflector are controlled so that it is located above the inlet of the air inlet, effectively preventing foreign objects from entering the engine flow path and significantly improving flight safety; in normal flight conditions, the airflow distribution is dynamically adjusted by controlling the deflector to be in the middle position of the inlet, reducing the airflow flowing into the foreign object removal flow path, ensuring sufficient airflow in the engine flow path, reducing aerodynamic losses, and improving the aerodynamic performance of the engine flow path. Therefore, while ensuring the foreign object removal function, the present invention takes into account the aerodynamic performance of the air inlet, thereby improving the overall safety and reliability of the aircraft. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 This is a schematic structural diagram of the foreign matter removal device of the present invention assembled on a bifurcated air intake duct.
[0021] Figure 2 Schematic diagram of the structure of the guide plate in the present invention.
[0022] Figure 3 Schematic diagram of the structure of the slider in the present invention.
[0023] Figure 4 Schematic diagram of the driving principle of the driving device in the present invention.
[0024] Figure 5 Schematic diagram of the position, posture and working mode of the guide plate in different working conditions in the present invention.
[0025] Figure 6 Schematic diagram of various parameters of the driving principle of the driving device in the present invention. DETAILED DESCRIPTION
[0026] like Figure 1 As shown in the figure, a forked air intake foreign object removal device with an adjustable guide mechanism in this embodiment includes a guide plate 7 and a drive device, which includes a screw motor 2, a rocker arm 3, a slider 4, a guide rail 5, and a guide plate 6. The screw motor 2 drives the slider 4 to move on the guide rail 5, and the slider 4 drives the guide plate 7 to move and rotate through the rocker arm 3, thereby achieving the switching of the airflow from the forked air intake entrance to the two bifurcated flow paths of the forked air intake.
[0027] like Figure 2As shown, the deflector 7 comprises a main body and a connecting portion. The cross-sectional shape of the main body is derived from the NACA6412 curve by transforming it. The specific transformation process involves stretching the NACA6412 curve twice along the chord direction, then bending both ends of the curve 90 degrees inwardly toward the concave side. The connecting portion of the deflector consists of cylindrical ends extending from each end of the main body. These cylindrical ends extend outward through the guide slots on the left and right sides of the bifurcated air intake duct 1, pass through the retaining slot of the guide plate 6, and are fixedly connected to one end of the rocker arm 3.
[0028] The guide plate 6 is fixedly connected to the protruding surfaces on the left and right sides of the bifurcated air inlet 1 by screws, and the limit grooves on the guide plate 6 coincide with the guide grooves on the left and right sides of the air inlet. The range of motion provided by the limit grooves is within the range of motion provided by the guide grooves. The cylindrical end of the guide plate connection part passes through the guide grooves and the limit grooves. The guide plate 6 is vertically connected to the guide rail 5. Figure 1 shown.
[0029] The bottom end of the slider 4 is fixedly connected to the guide rail slider, and the guide rail slider moves along the guide rail 5. The side end of the slider 4 is fixedly connected to one end of the screw of the screw motor 2. Under the drive of the motor, the screw moves along the extension direction of the guide rail 5, driving the slider 4 to reciprocate along the guide rail 5. One end of the slider 4 protrudes a cylindrical end, which is hingedly connected to one end of the rocker arm 3. The connection diagram of the slider and other components is as follows Figure 3 shown.
[0030] like Figure 4 As shown, in the above scheme, when the lead screw motor drives the lead screw up and down, the slider 4 reciprocates along the guide rail 5, and drives the rocker arm 3 to move via the cylindrical end protruding from its side. Because the rocker arm 3 is hingedly connected to the slider 4 at one end and fixedly connected to the guide plate 7 at the other end, and the guide plate 7 is limited in displacement by the limit groove of the guide plate 6, when the motor is driven back and forth, the guide plate can simultaneously achieve rotational motion while translating along the guide groove. The guide plate 7 is located at one end point of the limit groove, forming a first guide angle. The slider 4 drives the guide plate 7 to move to the other end of the limit groove through the rocker arm 3. When the guide plate 7 reaches the other end point of the limit groove at the first guide angle, the slider 4 continues to move. Under the limitation of the limit groove, the rocker arm 3 rotates relative to the slider 4, and the guide plate 7 rotates to form a second guide angle. When the guide plate 7 returns to the other end point of the limit groove at the second guide angle, the slider 4 continues to move. Under the limitation of the limit groove, the rocker arm 3 rotates relative to the slider 4, and the guide plate 7 restores the first guide angle.
[0031] like Figure 5As shown, in this embodiment, according to the above-mentioned movement mechanism, when the guide plate 7 is located at the lowest end (bottom dead center position) of the guide grooves on the left and right sides of the forked air inlet, the angle between its chord and the horizontal direction is 5° to 10°; when the guide plate moves to the upper end (top dead center position) of the guide groove, its posture rotates counterclockwise by about 10° relative to the bottom dead center position.
[0032] Combine Figure 5 The bifurcated inlet features a bulge on the upper inlet wall and a vent cavity 8 outside the inlet. When the aircraft is exposed to foreign matter, the deflector moves to the top of the guide groove, where it mates with the bulge to effectively prevent foreign matter from entering the engine flow path. A boundary layer suction slit is located downstream of the bulge, connecting the vent cavity. When the deflector is at its top, the vent cavity promptly discharges low-energy flow blocked by the deflector through the slit, preventing significant degradation of inlet performance. When the aircraft is in normal flight conditions, the deflector moves to the bottom of the guide groove, adjusting airflow distribution and reducing airflow into the foreign matter removal channel, thereby reducing aerodynamic losses.
[0033] like Figure 6 As shown, according to the above scheme, the translation distance and rotation angle of the guide plate are determined by the sliding distance of the slider. According to the specific control requirements, the translation and rotation of the guide plate can be achieved by controlling the reciprocating motion of the slider. The relationship between the three is determined by equations (1) to (3):
[0034]
[0035] Combine Figure 6 As shown, α is the angle (acute angle) between the rocker arm and the guide rail when it is at one end of the guide groove. This position corresponds to Figure 5 The bottom dead center position in the guide groove; β is the angle (acute angle) between the rocker arm and the guide rail when it is at the other end of the guide groove. This position corresponds to Figure 5 The difference between α and β is the rotation angle required to control the deflector.
[0036] l1 is the distance the slider moves on the guide rail, l2 is the distance the control guide plate moves in the guide groove, and r is the effective radius when rotating around one end of the rocker arm.
[0037] Among them, the four sides are r, l1, r, and l2, forming a quadrilateral with equal opposite sides; the length of the diagonal with sides r and l1 as adjacent sides is l3, and the angle between side l1 and diagonal l3 is θ.
[0038] Among them, when at the bottom dead center position, a circle is drawn with the intersection of edge l1 and edge r as the center and r as the radius, which is recorded as circle 1; edge l2 has only one intersection with circle 1, that is, the distance between the hinge point between the rocker arm and the slider and the guide groove is less than the effective radius when the rocker arm rotates, thereby ensuring that the guide plate can move smoothly in the guide groove without being stuck.
Claims
1. A bifurcated air intake foreign matter removal device with an adjustable flow guide mechanism, characterized in that: The invention comprises a guide plate (7) and a driving device arranged in the inlet of the forked air inlet, wherein guide grooves are arranged on both sides of the inlet of the forked air inlet, and the two ends of the guide plate (7) respectively extend out of the guide grooves on both sides of the inlet of the forked air inlet and are connected to the driving device, and the driving device drives the guide plate (7) to move along the guide groove of the forked air inlet, thereby realizing the switching of guiding the airflow at the inlet of the forked air inlet to the two forked flow channels of the forked air inlet.
2. The bifurcated air intake foreign matter removal device according to claim 1, characterized in that: The driving device comprises a screw motor (2), a rocker arm (3), a slider (4) and a guide rail (5); the two ends of the guide plate (7) respectively extend out of the guide grooves on both sides of the forked air inlet inlet and are fixedly connected to one end of the rocker arm (3); the other end of the rocker arm (3) is hinged to the slider (4); the screw motor (2) drives the slider (4) to move along the guide rail (5); and the extension direction of the guide rail (5) is parallel to the extension direction of the guide groove.
3. The bifurcated air intake foreign matter removal device according to claim 2, characterized in that: The driving device further comprises a guide plate (6) fixedly connected to the outer wall of the forked air inlet, wherein the guide plate (6) is provided with a limiting groove, and the two ends of the guide plate (7) respectively extend out of the guide grooves on both sides of the forked air inlet entrance, and are fixedly connected to one end of the rocker arm (3) after passing through the limiting groove. The range of movement provided by the limiting groove is within the range of movement provided by the guide groove. The guide plate (7) is located at one end point of the limiting groove, forming a first guide angle. The slider (4) drives the guide plate (7) to move toward the other end of the limiting groove through the rocker arm (3). When the guide plate reaches the other end point of the limiting groove at the first guide angle, the slider (4) continues to move. Under the limitation of the limiting groove, the rocker arm (3) rotates relative to the slider (4), and the guide plate (7) forms a second guide angle. When the guide plate returns to the other end point of the limiting groove at the second guide angle, the slider (4) continues to move. Under the limitation of the limiting groove, the rocker arm (3) rotates relative to the slider (4), and the guide plate (7) restores the first guide angle.
4. The bifurcated air intake foreign matter removal device according to claim 3, characterized in that: The guide plate includes a main body and a connecting part. The cross-sectional shape of the main body of the guide plate is determined by taking the cross-sectional shape of the NACA airfoil as the basic profile, stretching the basic profile n times along the chord direction to obtain a stretched profile, and synchronously deflecting the two ends of the stretched profile toward the inward concave side. The connecting part is a cylinder extending outward from the two ends of the main body, and the cylinder is fixedly connected to the rocker arm through the guide groove and the limit groove.
5. The bifurcated air intake foreign matter removal device according to claim 3, characterized in that: The calculation relationship between the moving distance of the guide plate, the moving distance of the slider and the rotation angle of the guide plate is: Among them, α is the acute angle between the rocker arm and the guide rail when it is at one end of the guide groove, β is the acute angle between the rocker arm and the guide rail when it is at the other end of the guide groove, the difference between α and β is the rotation angle required to control the guide plate, l1 is the moving distance of the slider, l2 is the moving distance of the guide plate, r is the effective radius when the rocker arm rotates, l3 is a diagonal line of the quadrilateral formed by the moving distance of the guide plate and the moving distance of the slider, and θ is the acute angle between the diagonal line and the extension direction of the guide rail.
6. The bifurcated air intake foreign matter removal device according to claim 5, characterized in that: The distance between the hinge point between the rocker arm and the slider and the guide groove is smaller than the effective radius of the rocker arm when it rotates.
7. A bifurcated air intake duct using the bifurcated air intake duct foreign matter removal device according to any one of claims 1 to 6, characterized in that: The bifurcated air intake duct comprises an engine flow duct that bifurcates upward and a foreign matter removal flow duct that bifurcates downward. The guide grooves on both sides of the bifurcated air intake duct inlet and the limit grooves on the guide plate (6) extend up and down. When the guide plate (7) is located at the lowermost end of the limit groove of the guide plate (6), the first angle between the chord of the guide plate (7) and the horizontal direction is in the range of 5° to 10°; when the guide plate (7) is located at the uppermost end of the limit groove of the guide plate (6), the chord of the guide plate (7) rotates 10° counterclockwise relative to the first angle; when the guide plate (7) is located at the uppermost end of the limit groove of the guide plate (6), foreign matter is prevented from entering the engine flow duct; when the guide plate (7) is located at the lowermost end of the limit groove of the guide plate (6), air flow distribution is adjusted to reduce the air flow flowing into the foreign matter removal flow duct.
8. The bifurcated air intake according to claim 7, characterized in that: A bulge is provided on the upper wall surface of the bifurcated air inlet inlet, and the bulge is located upstream of the guide plate (7). When the guide plate is located at the uppermost end of the limiting groove of the guide plate (6), it cooperates with the bulge surface to prevent foreign matter from entering the engine flow channel.
9. The bifurcated air intake according to claim 7, characterized in that: A boundary layer suction slit is provided downstream of the bulge. When the guide plate is located at the uppermost end of the limiting groove of the guide plate (6), the suction slit is used to timely discharge the low-energy flow formed by the obstruction of the guide plate.
10. The bifurcated air intake according to claim 9, characterized in that: An air release cavity (8) is provided outside the bifurcated air inlet duct, and the air release cavity (8) is used to accommodate the low-energy flow discharged from the suction slit.