Adjustable guide vanes for variable cycle engine fan and variable cycle engine
By designing multi-stage zoned adjustment of adjustable guide vanes, the problem of non-uniform flow field of variable cycle engine fan under variable flow field is solved, the stability margin and aerodynamic performance are improved, and the working requirements of different working conditions are met.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- BEIHANG UNIV
- Filing Date
- 2026-03-25
- Publication Date
- 2026-06-02
Smart Images
Figure CN122129449A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of aero-engine technology, and in particular to an adjustable guide vane for a variable cycle engine fan and a variable cycle engine. Background Technology
[0002] Aircraft engines are a crucial component of aircraft. An engine comprises a compressor (also called a fan), a combustion chamber, and a turbine. The compressor compresses air, which then mixes with fuel and burns in the combustion chamber, producing high-temperature, high-pressure combustion gases. These gases drive the turbine, propelling the gas through the exhaust nozzle and providing thrust for the aircraft. Adjustable guide vanes are an important component of the compressor; their primary function is to regulate airflow direction, ensuring the downstream rotor operates under suitable inflow conditions.
[0003] Variable cycle engines, as the power plant for next-generation fighter jets, combine the low fuel consumption of high-bypass turbofan engines under subsonic flight conditions with the high thrust of turbojet engines under supersonic conditions. By changing the geometry, size, or position of some engine components, the thermodynamic cycle parameters of the engine can be adjusted, allowing the engine to have suitable thermodynamic cycle parameters under various operating conditions, greatly improving aircraft performance. However, with the further development of variable cycle technology, the introduction of a third bypass duct has affected the inlet of the fan section, leading to non-uniform flow fields. Furthermore, existing adjustable guide vanes for engines are insufficient to meet the adjustment requirements of variable flow fields, affecting the stability margin of the variable cycle engine fan. Summary of the Invention
[0004] To solve the above-mentioned technical problems, or at least partially solve them, embodiments of this application provide an adjustable guide vane for a variable cycle engine fan and a variable cycle engine, which can effectively cope with the inlet flow non-uniformity and meet the adjustment requirements of variable flow fields.
[0005] In a first aspect, embodiments of this application provide an adjustable guide vane for a variable cycle engine fan, including a guide vane body and a drive mechanism; The guide vane body includes a front blade group, a middle blade group, and a rear blade group arranged sequentially along the air intake direction of the flow channel. Along the radial direction of the flow channel, the front blade group includes an upper front blade and a lower front blade, and the rear blade group includes an upper rear blade, a middle rear blade, and a lower rear blade; the middle blade is connected to the inner wall of the flow channel and is rotatable relative to the flow channel; The upper front leaflet, the upper rear leaflet, the lower front leaflet, and the lower rear leaflet are respectively connected to the middle leaflet and are rotatable relative to the middle leaflet; the middle rear leaflet is fixedly connected to the middle leaflet. The drive mechanism is configured to drive the middle blade, the upper front blade, the lower front blade, the upper rear blade, and the lower rear blade to rotate independently, respectively.
[0006] Optionally, the length ratio of the front blade group, the middle blade group, and the rear blade group along the axial direction of the flow channel is 3.5:3:3.5.
[0007] Optionally, the rotation angle range of the middle leaf is -15° to 15°.
[0008] Optionally, the rotation angle range of the upper front blade is -30° to 30°; The rotation angle range of the lower front blade is -30° to 30°.
[0009] Optionally, the rotation angle range of the upper rear blade is -30° to 30°; The rotation angle range of the lower rear leaflet is -30° to 30°.
[0010] Optionally, the length ratio of the upper rear blade, the middle rear blade, and the lower rear blade along the radial direction of the flow channel is 3:4:3; Along the radial direction of the flow channel, the length ratio of the upper front blade to the lower front blade is 1:1.
[0011] Optionally, the drive mechanism includes two central drive structures and four branch drive components; The two central drive structures are respectively disposed at the top and bottom of the middle blade, and the central drive structures are used to drive the middle blade to rotate; Two of the branch drive components are located at the top of the middle leaflet and are configured one-to-one with the upper front leaflet and the upper rear leaflet to drive the upper front leaflet and the upper rear leaflet to rotate independently, respectively. The other two branch drive components are located at the bottom of the middle leaf and are configured one-to-one with the lower front leaf and the lower rear leaf to drive the lower front leaf and the lower rear leaf to rotate independently, respectively.
[0012] Optionally, the central drive structure includes a middle blade drive gear connected to the middle blade, the middle blade drive gear being rotatable to drive the middle blade to rotate.
[0013] Optionally, the central drive structure further includes a front vane drive gear and a rear vane drive gear; The upper front leaf, the upper rear leaf, the lower front leaf, and the lower rear leaf are rotatably connected to the corresponding ends of the middle leaf via a gear rotating column; the branch drive assembly includes a gear pair, which has a helical gear end and a spur gear end; The spur gear end of the gear pair corresponding to the upper front leaf meshes with the front leaf drive gear located at the top of the middle leaf, and the front leaf drive gear located at the top of the middle leaf meshes with the gear rotating column of the upper front leaf; the spur gear end of the gear pair corresponding to the upper rear leaf meshes with the rear leaf drive gear located at the top of the middle leaf, and the rear leaf drive gear located at the top of the middle leaf meshes with the gear rotating column of the upper rear leaf. The spur gear end of the gear pair corresponding to the lower front leaf meshes with the front leaf drive gear located at the bottom of the middle leaf, and the front leaf drive gear located at the bottom of the middle leaf meshes with the gear rotating column of the lower front leaf; the spur gear end of the gear pair corresponding to the lower rear leaf meshes with the rear leaf drive gear located at the bottom of the middle leaf, and the rear leaf drive gear located at the bottom of the middle leaf meshes with the gear rotating column of the lower rear leaf.
[0014] Secondly, embodiments of this application provide a variable cycle engine, including adjustable guide vanes for a variable cycle engine fan as described above.
[0015] The adjustable guide vanes and variable cycle engine fan provided in this application embodiment, through the arrangement of a guide vane body and a drive mechanism, include a front vane group, a middle vane group, and a rear vane group arranged sequentially along the air intake direction of the flow channel. The front vane group includes an upper front vane and a lower front vane, and the rear vane group includes an upper rear vane, a middle rear vane, and a lower rear vane. The upper front vane, upper rear vane, lower front vane, and lower rear vane are respectively connected to the middle vane and can rotate relative to the middle vane. The middle rear vane is fixedly connected to the middle vane, and the middle vane is connected to the inner wall of the flow channel and can rotate relative to the flow channel. The drive mechanism drives the middle vane, upper front vane, lower front vane, and... The upper and lower rear blades rotate independently, enabling multi-level zoned adjustment of the guide vane body. This effectively addresses the non-uniformity of the inlet flow and the differences in flow at different blade heights, greatly improving the precision of flow field adjustment, expanding the adjustment range, and effectively reducing the impact of various engine adjustment components on the fan during engine mode changes. This significantly improves the intake conditions of the variable cycle engine fan, greatly enhances the stability margin of the variable cycle engine fan, and allows the fan to adapt to the working requirements of different operating conditions of the variable cycle engine, thereby improving the overall aerodynamic performance and adaptability of the engine. Attached Figure Description
[0016] Figure 1 This is a partial structural schematic diagram of a variable cycle engine according to an embodiment of this application; Figure 2 This is a schematic diagram of the adjustable guide vanes of a variable cycle engine fan according to an embodiment of this application; Figure 3 for Figure 2 Enlarged view of a local structure.
[0017] Explanation of reference numerals in the attached figures: 100. Fan; 10. Adjustable guide vane; 1. Guide vane body; 11. Front vane assembly; 111. Upper front vane; 112. Lower front vane; 12. Middle vane; 13. Rear vane assembly; 131. Upper rear vane; 132. Middle rear vane; 133. Lower rear vane; 141. First gear rotating column; 142. Second gear rotating column; 143. Third gear rotating column; 144. Fourth gear rotating column; 2. Drive mechanism; 21. Central drive structure; 210. Connecting shaft; 211. Middle vane drive gear; 212. Front vane drive gear; 213. Rear vane drive gear; 22. Branch drive assembly; 221. Gear pair; 2211. Helical gear end; 2212. Spur gear end; 3. Flow channel. Detailed Implementation
[0018] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the application and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present application, not the entire structure.
[0019] The term "comprising" and its variations as used herein are open-ended, meaning "including but not limited to". The concepts of "first," "second," etc., used in this application are only used to distinguish different devices, modules, or units, and are not intended to limit the order of functions performed by these devices, modules, or units or their interdependencies. It should be noted that the modifications "a" or "a plurality of" used in this application are illustrative rather than restrictive, and those skilled in the art should understand that, unless explicitly stated in the context, they should be understood as "one or more".
[0020] An aircraft engine includes a compressor (also called a fan), a combustion chamber, and a turbine. The compressor consists of a stator and a rotor. The compressor compresses air, which is then mixed with fuel and burned in the combustion chamber to produce high-temperature, high-pressure gas. This gas drives the turbine, causing it to be ejected through the exhaust nozzle, providing thrust for the aircraft. The rotor is a high-speed rotating component that performs work on the airflow, compressing the air stage by stage to provide high-pressure gas to the combustion chamber. The stator is a stationary component that primarily functions to adjust the direction of airflow.
[0021] Variable cycle engines, as the power plant for next-generation fighter jets, combine the low fuel consumption of high-bypass turbofan engines under subsonic flight conditions with the high thrust of turbojet engines under supersonic conditions. By changing the geometry, size, or position of some engine components, the thermodynamic cycle parameters of the engine can be adjusted, allowing the engine to have suitable thermodynamic cycle parameters under various operating conditions, greatly improving aircraft performance. With the further development of variable cycle technology, the introduction of a third bypass duct affects the inlet of the fan section, leading to uneven flow field. This affects the stability margin of the engine fan, and thus affects engine performance.
[0022] Based on this, embodiments of this application provide an adjustable guide vane for a variable cycle engine fan and a variable cycle engine. The adjustable guide vane can effectively address inlet flow non-uniformity and meet the adjustment requirements of variable flow fields. The adjustable guide vane for the variable cycle engine fan and the variable cycle engine provided in this application will be specifically described below with reference to the accompanying drawings and specific embodiments.
[0023] Reference Figures 1 to 3 As shown, this application embodiment provides an adjustable guide vane 10 for a variable cycle engine fan. The adjustable guide vane 10 is a stator of the fan 100 and is located at the front end of the fan 100 in the air intake direction.
[0024] The adjustable guide vane 10 includes a guide vane body 1 and a drive mechanism 2. The guide vane body 1 includes a front blade group 11, a middle blade group 12, and a rear blade group 13 arranged sequentially along the air intake direction of the flow channel 3. That is, according to the order of contact with the airflow, the blades are arranged in the order of front blade group 11, middle blade group 12, and rear blade group 13.
[0025] Along the radial direction of the flow channel 3, the front blade group 11 includes an upper front blade 111 and a lower front blade 112, and the rear blade group 13 includes an upper rear blade 131, a middle rear blade 132 and a lower rear blade 133.
[0026] The middle blade 12 is connected to the inner wall of the flow channel 3 and can rotate relative to the flow channel 3. The upper front blade 111, upper rear blade 131, lower front blade 112, and lower rear blade 133 are respectively connected to the middle blade 12 and can rotate relative to the middle blade 12. Among them, the middle rear blade 132 is fixedly connected to the middle blade 12.
[0027] The drive mechanism 2 is configured to drive the middle blade 12, the upper front blade 111, the lower front blade 112, the upper rear blade 131, and the lower rear blade 133 to rotate independently.
[0028] In other words, each part of the guide vane body 1 can be adjusted independently. Specifically, it can be adjusted according to the airflow angle and uniformity of the incoming flow, as well as the flow characteristics of the blade tip, blade bottom and hub regions of the fan rotor in the variable cycle engine mode and the required optimal inlet airflow angle.
[0029] For example, the middle blade 12 serves as the rotation reference and load-bearing support for the entire adjustable guide vane 10. The middle blade 12 can be adjusted first to rotate to the target angle. When the middle blade 12 rotates, it drives the front blade group 11 and the rear blade group 13 to rotate synchronously.
[0030] The adjustment of the front blade group 11 and the rear blade group 13 uses the adjustment angle of the middle blade 12 as a reference. After the middle blade 12 is adjusted, the upper front blade 111 and the lower front blade 112 are adjusted independently according to the incoming flow conditions and the current angle of the middle blade 12. The upper rear blade 131 and the lower rear blade 133 are adjusted independently according to the requirements of the rotor blade tip and blade bottom and the current angle of the middle blade 12.
[0031] The rotation angle of the middle blade 12 can be determined by comprehensively considering the airflow angle of the incoming flow and the optimal inlet airflow angle required by the rotor in the mode of the variable cycle engine, while avoiding excessive rotation angles between the front blade group 11 and the middle blade 12, and between the rear blade group 13 and the middle blade 12, which could lead to flow separation.
[0032] Due to the presence of the third bypass of the adaptive variable cycle engine, the flow field near the upper wall of the flow channel 3 is significantly different from that near the lower wall. In addition, the incoming flow is also uneven. Therefore, by adjusting the rotation angles of the upper front blade 111 and the lower front blade 112 respectively, the incoming flow can better enter the adjustable guide vane 10. The rotation positions of the upper front blade 111 and the lower front blade 112 are adjusted to match the flow channel 3, so that the uneven incoming flow can enter the flow channel 3 more smoothly, avoiding blockage at the inlet and causing airflow loss.
[0033] The airflow then enters the middle blade 12, which has been adjusted to the target angle, for a second deflection, and finally flows through the rear blade assembly 13 for fine control. The rotation angle of the upper rear blade 131 primarily considers the flow in the blade tip region and its connection with the middle blade 12, avoiding excessive rotation angles between the upper, middle, and lower blades, which could lead to large velocity differences in the airflow and additional losses, thus minimizing instability in the blade tip region. The flow in the rotor blade mid-region corresponding to the middle rear blade 132 is relatively stable; therefore, the middle rear blade 132 is fixed to the middle blade 12, and its rotation angle is consistent with that of the middle blade 12. The rotation angle of the lower rear blade 133 primarily considers the flow in the blade bottom hub region and its connection with the middle blade 12. Specifically, its rotation angle can be determined based on the required airflow intake angle of the rotor blade bottom hub of the variable cycle engine fan 100 and the adjustment angle of the middle blade 12, to closely match the requirements of the adaptive variable cycle engine for fine airflow control and ensure the stability of the adaptive variable cycle engine fan 100.
[0034] The implementation of this application, as described above, allows airflow to enter the adjustable guide vane 10 with low loss. Regional adjustment effectively solves the flow field inhomogeneity problems caused by modal changes and the influence of the third duct. Multi-stage deflection reduces the deflection angle of the airflow at each stage, greatly suppressing flow separation and ensuring the quality of the airflow passing through the adjustable guide vane 10. Furthermore, it expands the adjustment range of the adjustable guide vane 10 by distributing large adjustment angles to the front vane group 11, middle vane 12, and rear vane group 13 to meet the operating requirements of the variable cycle engine fan 100. In addition, the rear vane group 13, targeting the rotor tip, blade bottom, and hub areas of the fan 100, greatly avoids rotor instability by adjusting the upper rear vane 131 and lower rear vane 133 in separate zones, thus widening the stability margin of the fan 100.
[0035] For example, multiple adjustable guide vanes 10 can be configured, with the multiple adjustable guide vanes 10 evenly distributed along the circumference of the flow channel 3, and the width of the adjustable guide vanes 10 matching the size of the flow channel 3. The specific number of adjustable guide vanes 10 can be determined based on the specific conditions of the rotor, and while ensuring sufficient stability margin and aerodynamic performance of the rotor, it can also take into account factors such as reducing the complexity of the engine. In addition, the guide vane body 1 can be configured as a symmetrical guide vane without curvature.
[0036] In some embodiments, the length ratio of the front blade group 11, the middle blade 12 and the rear blade group 13 along the axial direction of the flow channel 3 can be set to 3.5:3:3.5.
[0037] Reference Figure 2 As shown, the axial direction here is specifically... Figure 2 The X-direction.
[0038] This ensures that the front blade group 11 and the rear blade group 13 have appropriate lengths to guarantee the effects of initial and fine deflection of the airflow. The length of the middle blade 12 matches its coarse adjustment function, so that the deflection angle of each section of the airflow is reasonably distributed, further suppressing flow separation, reducing the flow loss of the airflow in the guide vane, and ensuring the aerodynamic effect of multi-stage deflection.
[0039] In some embodiments, the rotation angle of the middle leaf 12 can be set between -15° and 15°.
[0040] For example, the middle blade 12 can rotate clockwise or counterclockwise. For instance, the rotation angle of the middle blade 12 can be set to 5°, 10°, or 15°.
[0041] Since the entire adjustable guide vane 10 is connected to the inner wall of the flow channel 3 through the middle vane 12, by setting the rotation angle of the middle vane 12 within the relatively small deflection angle range mentioned above, the structural stability of the middle vane 12 and the coarse airflow adjustment function are taken into account. This avoids the flow field turbulence caused by the large-angle rotation of the middle vane 12, while adapting to the stable flow characteristics of the rotor blade region, achieving smooth coarse airflow adjustment, and smoothly connecting the initial deflection of the front vane group 11 and the fine deflection of the rear vane group 13, preventing flow separation caused by excessive angle deviation.
[0042] In some embodiments, the rotation angle of the upper front leaf 111 can be set between -30° and 30°.
[0043] For example, the upper front vane 111 can rotate clockwise or counterclockwise. The rotation angle of the upper front vane 111 is, for example, 10°, 15°, 20°, or 30°. The specific rotation angle of the upper front vane 111 can be determined based on the intake angle of the airflow near the upper wall and the adjustment angle of the middle vane 12.
[0044] In some embodiments, the rotation angle of the lower front leaf 112 can be set between -30° and 30°.
[0045] For example, the lower front blade 112 can rotate clockwise or counterclockwise. The rotation angle of the lower front blade 112 is, for example, 10°, 15°, 20°, or 30°. The rotation angle of the lower front blade 112 can be determined based on the air intake angle of the flow from the lower wall of the flow channel 3 and the adjustment angle of the middle blade 12.
[0046] By setting the rotation angles of the upper front blade 111 and the lower front blade 112 within the aforementioned range, the large angle adjustment range can flexibly adapt to the changes in the incoming airflow angle in the radial upper and lower regions of the flow channel. In particular, it can precisely match different incoming flow angles to address the differences in the upper wall flow field caused by the third duct, allowing the airflow to smoothly enter the flow channel, avoiding inlet blockage, reducing total pressure loss, and laying a low-loss intake foundation for subsequent airflow deflection.
[0047] In some embodiments, the rotation angle of the upper rear leaf 131 can be set between -30° and 30°.
[0048] For example, the upper rear leaflet 131 can rotate clockwise or counterclockwise. The rotation angle of the upper rear leaflet 131 is, for example, 10°, 15°, 20°, or 30°.
[0049] In some embodiments, the rotation angle of the lower rear leaf 133 can be set between -30° and 30°.
[0050] For example, the lower rear leaflet 133 can rotate clockwise or counterclockwise. The rotation angle of the lower rear leaflet 133 is, for example, 10°, 15°, 20°, or 30°.
[0051] By setting the rotation angles of the upper rear blade 131 and the lower rear blade 133 within the aforementioned range, the large angle adjustment range can flexibly adapt to the flow characteristics requirements of the rotor blade tip, blade bottom hub, and other highly sensitive areas under different modes of the variable cycle engine, thereby achieving fine deflection of the airflow, accurately matching the optimal inlet airflow angle in this area, suppressing blade tip instability and flow separation in the blade bottom hub area, and widening the stability margin of the fan 100.
[0052] In some embodiments, the length ratio of the upper rear blade 131, the middle rear blade 132, and the lower rear blade 133 along the radial direction of the flow channel 3 is 3:4:3.
[0053] Reference Figure 2 As shown, the radial direction of flow channel 3 here can be specifically... Figure 2 The ratio of the lengths of the upper posterior leaf 131, the middle posterior leaf 132, and the lower posterior leaf 133 along the Y direction is 3:4:3.
[0054] This configuration allows for precise matching of the radial structure and flow characteristics of the rotor blade tip, blade middle, and blade bottom hub. The middle and rear blades are proportioned 132 to match the main flow area in the blade middle, while the upper and lower rear blades are proportioned 131 and 133 to match the small, highly sensitive areas at the blade tip and blade bottom, respectively. This improves the targeting and effectiveness of the guide vane zonal adjustment, optimizes the overall flow field distribution, and further ensures the stability of the adaptive variable cycle engine fan 100.
[0055] Continue to refer to Figure 2 As shown, in some embodiments, along the radial direction of the flow channel 3 ( Figure 2 In the Y direction, the length ratio of the upper anterior leaf 111 to the lower anterior leaf 112 is 1:1.
[0056] This configuration can adapt to the spatial distribution of incoming flow in the radial upper and lower regions of the flow channel 3, further ensuring the balance of the incoming flow adjustment effect in the upper and lower regions, and further improving the intake conditions.
[0057] Reference Figure 2 and Figure 3 As shown, in some embodiments, the drive mechanism 2 includes two central drive structures 21 and four branch drive components 22; Two central drive structures 21 are respectively disposed at the top and bottom of the middle blade 12, and the central drive structures 21 are used to drive the middle blade 12 to rotate.
[0058] Two branch drive components 22 are located at the top of the middle leaf 12 and are configured one-to-one with the upper front leaf 111 and the upper rear leaf 131, respectively, to drive the upper front leaf 111 and the upper rear leaf 131 to rotate independently. The other two branch drive components 22 are located at the bottom of the middle leaf 12 and are configured one-to-one with the lower front leaf 112 and the lower rear leaf 133, respectively, to drive the lower front leaf 112 and the lower rear leaf 133 to rotate independently.
[0059] By placing the two central drive structures 21 at the top and bottom of the middle blade 12 respectively, the overall force balance of the middle blade 12 is improved, the stability of the rotation adjustment of the middle blade 12 is enhanced, and the deformation or jamming caused by uneven force is avoided.
[0060] By making the four branch drive components 22 correspond one-to-one with the upper front blade 111, the lower front blade 112, the upper rear blade 131, and the lower rear blade 133, independent and precise driving of each part of the guide vane body 1 is achieved, avoiding drive interference, thereby further ensuring the accuracy of zoned fine adjustment.
[0061] In some embodiments, the central drive structure 21 includes a middle leaf drive gear 211 connected to the middle leaf 12, the middle leaf drive gear 211 being rotatable to drive the middle leaf 12 to rotate.
[0062] In a specific implementation, a central driver may also be included to drive the middle blade drive gear 211 to rotate. For example, the central driver may be a drive motor, which is located outside the flow channel 3, with its output shaft extending into the flow channel 3, and the middle blade drive gear 211 connected to the output shaft of the drive motor.
[0063] The rotation of the middle blade 12 is driven by the middle blade drive gear 211, which improves the transmission accuracy, adapts to the high temperature and high pressure working conditions of the engine, ensures the accuracy of the rotation adjustment angle of the middle blade 12 and the structural reliability, avoids drive failure, and ensures the stability and accuracy of the airflow coarse adjustment link.
[0064] Of course, in other implementations, the central drive may also include hydraulic motors, etc.
[0065] Continue to combine Figure 2 and Figure 3 As shown, the central drive structure 21 includes a connecting shaft 210, which is arranged to pass through the middle blade 12 along the Y direction. A middle blade drive gear 211 is connected to each end of the connecting shaft 210.
[0066] In some embodiments, the central drive structure 21 further includes a front vane drive gear 212 and a rear vane drive gear 213. The upper front vane 111, the upper rear vane 131, the lower front vane 112, and the lower rear vane 133 are rotatably connected to the corresponding ends of the middle vane 12 via gear rotating columns.
[0067] Specifically, the upper front leaf 111 is connected to the top of the middle leaf 12 via the first gear rotating column 141, the upper rear leaf 131 is connected to the top of the middle leaf 12 via the second gear rotating column 142, the lower front leaf 112 is connected to the bottom of the middle leaf 12 via the third gear rotating column 143, and the lower rear leaf 133 is connected to the bottom of the middle leaf 12 via the fourth gear rotating column 144.
[0068] For example, the middle blade drive gear 211, the front blade drive gear 212, and the rear blade drive gear 213 can be cylindrical gears. The front blade drive gear 212 and the rear blade drive gear 213 can be respectively sleeved on the connecting shaft 210 and can rotate relative to the connecting shaft 210.
[0069] The branch drive assembly 22 includes a gear pair 221, which has a helical gear end 2211 and a spur gear end 2212.
[0070] The spur gear end 2212 of the gear pair 221 corresponding to the upper front leaf 111 meshes with the front leaf drive gear 212 located at the top of the middle leaf 12, and the front leaf drive gear 212 located at the top of the middle leaf 12 meshes with the first gear rotating column 141.
[0071] The spur gear end 2212 of the gear pair 221 corresponding to the upper rear leaf 131 meshes with the rear leaf drive gear 213 located at the top of the middle leaf 12, and the rear leaf drive gear 213 located at the top of the middle leaf 12 meshes with the second gear rotating column 142.
[0072] The spur gear end 2212 of the gear pair 221 corresponding to the lower front leaf 112 meshes with the front leaf drive gear 212 located at the bottom of the middle leaf 12, and the front leaf drive gear 212 located at the bottom of the middle leaf 12 meshes with the third gear rotating column 143.
[0073] The spur gear end 2212 of the gear pair 221 corresponding to the lower rear leaf 133 meshes with the rear leaf drive gear 213 located at the bottom of the middle leaf 12, and the rear leaf drive gear 213 located at the bottom of the middle leaf 12 meshes with the fourth gear rotating column 144.
[0074] In a specific implementation, branch drivers can also be set, with each gear pair 221 corresponding to a branch driver. Specifically, the helical gear end 2211 of the gear pair 221 is connected to the branch driver, which may include a drive motor, and a bevel gear is provided on the output shaft of the drive motor, which meshes with the helical gear end 2211 of the gear pair 221.
[0075] Taking the upper front leaf 111 as an example: Since the helical gear end 2211 of the gear pair 221 corresponding to the upper front leaf 111 meshes with the bevel gear of the drive motor, when the drive motor corresponding to the upper front leaf 111 is working, it drives the gear pair 221 to rotate. Since the spur gear end 2212 of the gear pair 221 meshes with the front leaf drive gear 212 corresponding to the upper front leaf 111, the front leaf drive gear 212 rotates under the drive of the gear pair 221, thereby driving the first gear rotating column 141 meshing with the front leaf drive gear 212 to rotate, thus realizing the rotation of the upper front leaf 111.
[0076] The rotation principles of the lower front leaf 112, the upper rear leaf 131, and the lower rear leaf 133 are the same as those of the upper front leaf 111, and will not be described in detail here.
[0077] By giving gear pair 221 a helical gear end 2211 and a spur gear end 2212, the direction of power input is reversed, adapting to the installation space and power transmission requirements within the engine flow channel. Each blade section is rotatably connected to the middle blade 12 via a gear rotating column. Combined with the gear meshing transmission method, the angular accuracy of rotational adjustment of each part of the guide vane body 1 is significantly improved, ensuring the effect of fine-grained zone adjustment. By having each of the aforementioned drive gears mesh with the corresponding blade's gear rotating column, precise power transmission is achieved, avoiding transmission interference and ensuring the reliability of independent rotation of each blade.
[0078] By setting the drive mechanism 2 as described above, the overall structural compactness of the drive mechanism 2 is improved, the space occupied by the drive mechanism 2 is reduced, and thus the intake effect of the engine is guaranteed.
[0079] The adjustable guide vane 10 provided in this application embodiment is a multi-stage locally adjustable guide vane, which can be adjusted in sections according to the flow characteristics of different areas of the blade, thereby increasing the adjustment range. It can adjust the inlet airflow angle of the fan 100 over a wide range to reduce the influence of various adjustment components of the variable cycle engine on the fan 100 when the mode changes, thereby greatly improving the intake conditions of the variable cycle engine fan 100 and increasing its stability margin.
[0080] This application also provides a variable cycle engine, including a fan 100 (i.e., a compressor), a combustion chamber, a turbine, and a tail nozzle.
[0081] The fan 100 includes an adjustable guide vane 10, which is specifically the stator of the fan 100, and the adjustable guide vane 10 is located at the front end in the air intake direction of the fan 100.
[0082] The adjustable guide vane 10 in this embodiment has the same specific structure and implementation principle as the adjustable guide vane 10 provided in the above embodiments, and can bring the same or similar technical effects. It will not be described in detail here. For details, please refer to the description of the above embodiments.
[0083] The above description is merely an embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of disclosure in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.
Claims
1. An adjustable guide vane for a variable cycle engine fan, characterized in that, Includes the guide vane body and the drive mechanism; The guide vane body includes a front blade group, a middle blade group, and a rear blade group arranged sequentially along the air intake direction of the flow channel. Along the radial direction of the flow channel, the front blade group includes an upper front blade and a lower front blade, and the rear blade group includes an upper rear blade, a middle rear blade, and a lower rear blade; the middle blade is connected to the inner wall of the flow channel and is rotatable relative to the flow channel; The upper front leaflet, the upper rear leaflet, the lower front leaflet, and the lower rear leaflet are respectively connected to the middle leaflet and are rotatable relative to the middle leaflet; the middle rear leaflet is fixedly connected to the middle leaflet. The drive mechanism is configured to drive the middle blade, the upper front blade, the lower front blade, the upper rear blade, and the lower rear blade to rotate independently, respectively.
2. The adjustable guide vanes of the variable cycle engine fan according to claim 1, characterized in that, Along the axial direction of the flow channel, the length ratio of the front blade group, the middle blade, and the rear blade group is 3.5:3:3.
5.
3. The adjustable guide vanes of the variable cycle engine fan according to claim 1, characterized in that, The rotation angle range of the middle blade is -15° to 15°.
4. The adjustable guide vanes of the variable cycle engine fan according to claim 1, characterized in that, The rotation angle range of the upper front blade is -30° to 30°; The rotation angle range of the lower front blade is -30° to 30°.
5. The adjustable guide vanes of the variable cycle engine fan according to claim 1, characterized in that, The rotation angle range of the upper rear blade is -30° to 30°; The rotation angle range of the lower rear leaflet is -30° to 30°.
6. The adjustable guide vanes of the variable cycle engine fan according to claim 1, characterized in that, Along the radial direction of the flow channel, the length ratio of the upper rear blade, the middle rear blade, and the lower rear blade is 3:4:3; Along the radial direction of the flow channel, the length ratio of the upper front blade to the lower front blade is 1:
1.
7. The adjustable guide vanes of the variable cycle engine fan according to any one of claims 1 to 6, characterized in that, The drive mechanism includes two central drive structures and four branch drive components; The two central drive structures are respectively disposed at the top and bottom of the middle blade, and the central drive structures are used to drive the middle blade to rotate; Two of the branch drive components are located at the top of the middle leaflet and are configured one-to-one with the upper front leaflet and the upper rear leaflet to drive the upper front leaflet and the upper rear leaflet to rotate independently, respectively. The other two branch drive components are located at the bottom of the middle leaf and are configured one-to-one with the lower front leaf and the lower rear leaf to drive the lower front leaf and the lower rear leaf to rotate independently, respectively.
8. The adjustable guide vanes of the variable cycle engine fan according to claim 7, characterized in that, The central drive structure includes a middle blade drive gear connected to the middle blade, the middle blade drive gear being rotatable to drive the middle blade to rotate.
9. The adjustable guide vanes of the variable cycle engine fan according to claim 8, characterized in that, The central drive structure also includes a front vane drive gear and a rear vane drive gear; The upper front leaf, the upper rear leaf, the lower front leaf, and the lower rear leaf are rotatably connected to the corresponding ends of the middle leaf via a gear rotating column; the branch drive assembly includes a gear pair, which has a helical gear end and a spur gear end; The spur gear end of the gear pair corresponding to the upper front leaf meshes with the front leaf drive gear located at the top of the middle leaf, and the front leaf drive gear located at the top of the middle leaf meshes with the gear rotating column of the upper front leaf; the spur gear end of the gear pair corresponding to the upper rear leaf meshes with the rear leaf drive gear located at the top of the middle leaf, and the rear leaf drive gear located at the top of the middle leaf meshes with the gear rotating column of the upper rear leaf. The spur gear end of the gear pair corresponding to the lower front leaf meshes with the front leaf drive gear located at the bottom of the middle leaf, and the front leaf drive gear located at the bottom of the middle leaf meshes with the gear rotating column of the lower front leaf; the spur gear end of the gear pair corresponding to the lower rear leaf meshes with the rear leaf drive gear located at the bottom of the middle leaf, and the rear leaf drive gear located at the bottom of the middle leaf meshes with the gear rotating column of the lower rear leaf.
10. A variable cycle engine, characterized in that, Includes the adjustable guide vane as described in any one of claims 1 to 9.