Aero-engine fan impact vibration test equipment and method

Abstract

The invention discloses aero-engine fan impact vibration testing equipment and method, and belongs to the technical field of aero-engine testing. The equipment comprises a test box, the interior of which is a sealed cavity; the temperature adjusting unit is used for changing the temperature in the sealed cavity; the transmitting unit is used for transmitting compressed air shock waves to enter the sealed cavity through the transmitting tube and impact the rotating fan test piece; the angle adjusting unit is used for changing the inclination angle of the launching tube so as to change the impact angle; and the vibration response pickup unit is used for capturing the vibration state of the fan test piece after being impacted. By integrating the temperature, angle and speed adjusting functions, complex working conditions of different working temperatures and different impact angles and speeds can be simulated, and accurate measurement of the vibration response after the fan blade is impacted by the foreign matter is achieved. According to the invention, an efficient and accurate test platform is provided for evaluating the shock resistance and vibration characteristics of the composite material fan blade in a complex environment.

Description

Technical Field

[0001] This invention relates to the field of aero-engine testing technology, and more specifically to an aero-engine fan impact vibration testing device and method. Background Technology

[0002] To meet the lightweight design requirements of aero-engines, fiber composite materials are increasingly being used in aero-engine fan blades. When aircraft fly at low altitudes or encounter severe weather, aero-engine fan blades inevitably suffer high-speed impacts from foreign objects such as birds and hail. These impacts can cause damage to the composite blades, create stress concentration, and consequently affect their fatigue life. Severe impacts can even induce overall structural deformation of the engine fan, leading to abnormal vibrations and various malfunctions during aero-engine operation. Existing bird strike tests primarily focus on post-impact stress analysis, lacking effective testing platforms to support the dynamic response during the impact process and the effects of different impact angles and velocities on rotating fan blades. Furthermore, changes in ambient temperature during flight significantly alter the material properties of fiber composite blades, affecting their impact resistance and vibration response. However, existing testing platforms and research largely concentrate on vibration simulation and testing under specific environments (such as low-pressure vacuum), failing to effectively control and simulate the temperature of the testing environment.

[0003] Therefore, in order to accurately assess the safety and reliability of aero-engine fan blades under complex operating conditions, it is crucial to conduct impact vibration tests simulating different impact angles and velocities of foreign objects at different operating temperatures. Summary of the Invention

[0004] The purpose of this invention is to provide an impact vibration testing device and method for aero-engine fans, so as to accurately simulate the impact vibration test of aero-engine fans under different operating temperatures and different impact angles and impact velocities, and to pick up the vibration response.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: An impact vibration testing device for an aircraft engine fan includes: The test chamber has a sealed cavity inside to house and drive the fan test piece to rotate. The test chamber is equipped with a launch inlet and an observation window that communicate with the sealed cavity. Temperature regulation unit, used to change the temperature inside the sealed cavity; The launching unit is connected to the launching inlet via the launching tube. A valve is installed between the launching unit and the launching tube. A speed measuring device is installed on the launching tube. The launching unit emits compressed air shock waves that enter the sealed cavity through the launching tube and impact the rotating fan test piece. An angle adjustment unit is used to change the tilt angle of the transmitter tube, thereby changing the angle at which the compressed air shock wave impacts the fan test piece. The vibration response pickup unit is used to capture the vibration state of the fan test piece after it has been impacted in real time through the observation window.

[0006] Furthermore, the temperature regulating unit includes: The test chamber is equipped with a liquid nitrogen injection port that communicates with the sealed cavity. The liquid nitrogen injection device is connected to the liquid nitrogen injection port via a liquid nitrogen pipeline. The liquid nitrogen injection device injects liquid nitrogen into the sealed cavity via the liquid nitrogen pipeline for cooling and reducing the temperature inside the sealed cavity. A heating device is installed inside the sealed cavity to heat and increase the temperature inside the sealed cavity; A temperature sensor, with its sensing end located inside a sealed cavity, is used to monitor the temperature inside the sealed cavity.

[0007] Furthermore, the heating device is an annular heating device, which is arranged around the periphery of the fan test piece; the annular heating device includes an annular heat insulation layer and multiple electromagnetic heaters arranged at equal intervals on the annular heat insulation layer.

[0008] Furthermore, the launching unit includes a gas source, a flexible connecting pipe, and a soft isolation sleeve; the gas source is connected to one end of the launching tube via the flexible connecting pipe; the soft isolation sleeve is made of a material with heat insulation and resilience, and its configuration is a rotating stepped type. The soft isolation sleeve fills the space between the launching inlet and the other end of the launching tube. The edge of the soft isolation sleeve is connected to the launching inlet, and an assembly hole is provided in the middle of the soft isolation sleeve. The other end of the launching tube is connected to the assembly hole.

[0009] Furthermore, the air source includes a high-pressure airbag and an air compressor. The high-pressure airbag is connected to one end of the launching tube via a flexible connecting tube, and the air compressor is connected to the high-pressure airbag via an air supply pipe. A pressure sensor is connected to the high-pressure airbag or the air supply pipe.

[0010] Furthermore, the angle adjustment unit includes a base and a pushing hydraulic cylinder. The fixed end of the pushing hydraulic cylinder is hinged to the base, and the telescopic end of the pushing hydraulic cylinder is hinged to the launching tube. The tilt angle of the launching tube is changed by extending and retracting the telescopic end of the pushing hydraulic cylinder relative to the fixed end.

[0011] Furthermore, a drive motor is provided on one side of the test box, and the output shaft of the drive motor is connected to the fan test piece via the test spindle.

[0012] Furthermore, a protective frame is provided inside the test chamber, which surrounds the outside of the fan test piece to block fragments of the fan test piece when it is impacted and breaks.

[0013] Furthermore, the test box is provided with a light-transmitting window that communicates with the sealed cavity. The light-transmitting window is used to supplement light into the sealed cavity when the vibration response pickup unit takes pictures.

[0014] A method for testing the impact vibration of an aero-engine fan, using the aforementioned aero-engine fan impact vibration testing equipment, is described below: S1. Installation and pressure control; The fan test piece is assembled in the sealed cavity, and the sealed cavity is evacuated. At the same time, the pressure in the sealed cavity is monitored in real time by a pressure sensor until the air pressure in the sealed cavity reaches and stabilizes at the set value. S2, Drive the fan test piece to rotate; The fan test piece is driven to rotate at a set speed within the sealed cavity of the test chamber; S3. Change the temperature inside the sealed cavity 11 to the set temperature through the temperature adjustment unit; S4. Impact angle and speed settings; The angle adjustment unit changes the tilt angle of the transmitter tube to change the angle of the compressed air shock wave to strike the fan test piece at a set angle. The pressure data of compressed air inside the high-pressure airbag is monitored in real time by a pressure sensor. The high-pressure airbag is inflated by an air compressor until the pressure inside the high-pressure airbag reaches the set pressure value corresponding to the preset impact speed. S5, Shockwave emission and impact; The valve is opened instantaneously to emit a compressed air shock wave through the transmitting unit. The actual speed of the compressed air shock wave is monitored and recorded in real time by the speed measuring device. The compressed air shock wave enters the sealed cavity through the transmitting tube and impacts the rotating fan test piece. S6. Vibration response acquisition and processing; The vibration response pickup unit captures and photographs the vibration state of the fan test piece after it is impacted in real time, and processes the captured data to obtain the vibration response signal of the fan test piece. S7. Repeated testing and data recording; Change the set temperature in S3, the impact angle in S4, and / or the set pressure of the high-pressure airbag, and repeat the above steps S1-S6 to conduct multiple sets of comparative tests under different working conditions. Record all test data for subsequent analysis of the effects of different temperatures, impact angles, and speeds on the impact vibration characteristics of the fan test piece.

[0015] Compared with the prior art, the aero-engine fan impact vibration testing equipment and method of the present invention have achieved the following significant technical effects: 1. This invention, by integrating a temperature control unit, an angle adjustment unit, and a launch unit, achieves for the first time multi-condition coupled simulation of aero-engine fan blades on a single test platform. Specifically, the temperature control unit within the test chamber can accurately simulate different operating environment temperatures, the angle adjustment unit can flexibly change the incident angle of the shock wave, and the launch unit precisely controls the impact velocity by adjusting the air pressure. This realistically reproduces the comprehensive operating conditions of fan blades subjected to foreign object impacts under complex flight environments, providing more accurate experimental data for evaluating the impact resistance performance of the blades.

[0016] 2. This invention uses compressed air shock waves to simulate foreign object impact, combined with vibration response acquisition by a high-speed camera, to achieve non-contact, high-precision dynamic response measurement. Compressed air shock waves offer good repeatability and controllable velocity, avoiding secondary damage or fragment interference that may occur with traditional solid projectile impacts. Real-time imaging via an observation window and processing using digital image correlation methods accurately captures the blade's deformation process, vibration modes, and damping characteristics at the moment of impact and beyond, significantly improving the accuracy and reliability of vibration response testing.

[0017] 3. This invention achieves uniform and rapid temperature regulation within the test chamber through the coordinated operation of a ring-shaped heating device and a liquid nitrogen injection device. The ring-shaped heating device is evenly spaced around the fan, achieving uniform heating as the blades rotate, thus avoiding localized overheating; the liquid nitrogen injection provides rapid cooling, realistically simulating a high-altitude, low-temperature environment. Furthermore, the design of the soft isolation sleeve and flexible connecting tube ensures both the flexibility of the launch angle adjustment and the sealing of the test chamber, guaranteeing the feasibility and accuracy of multi-angle impact testing.

[0018] In summary, this invention provides an efficient and accurate testing platform for studying the shock resistance and vibration characteristics of aero-engine fan blades under complex operating conditions, which is of great significance for guiding the optimized design of composite material fan blades and improving the safety and reliability of aero-engines. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the aircraft engine fan impact vibration testing equipment according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the test box structure according to an embodiment of the present invention; Figure 3 for Figure 2 Sectional view of AA; Figure 4 This is a schematic diagram of the test spindle structure according to an embodiment of the present invention; Figure 5 This is a front view of the engine fan according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the annular heating device according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the protective frame structure according to an embodiment of the present invention; Figure 8 This is a schematic diagram of the structure of the protective frame and the annular heating device assembled into one unit according to an embodiment of the present invention; Figure 9 This is a schematic diagram of the structure of the test chamber door in an embodiment of the present invention; Figure 10 This is a half-sectional perspective view of the soft isolation sleeve according to an embodiment of the present invention; Figure 11 This is a front view of the transmitting unit and the angle adjustment unit according to an embodiment of the present invention; Figure 12 This is a left view of the transmitting unit and the angle adjustment unit according to an embodiment of the present invention; Figure 13 This is a top view of the transmitting unit and the angle adjustment unit according to an embodiment of the present invention; in, 1. Test chamber; 101. Chamber body; 102. Chamber door; 11. Sealed cavity; 12. Launch inlet; 13. Observation window; 14. Drive motor; 15. Test spindle; 151. Bearing support frame; 152. Bearing; 16. Fixture; 17. Protective frame; 18. Light transmission window; 19. Air extraction port; 21. Liquid nitrogen injection port; 221. Annular heat insulation layer; 222. Electromagnetic heater; 23. Temperature sensor; 31. Launch tube; 311. Velocity sensor; 32. First solenoid valve; 331. High-pressure airbag; 332. Air compressor; 34. Flexible connecting pipe; 35. Soft isolation sleeve; 351. Assembly hole; 36. Air supply pipe; 37. Second pressure sensor; 38. Second solenoid valve; 39. Exhaust valve; 41. Base; 42. Pushing hydraulic cylinder; 5. High-speed camera; 6. Fan test piece. Detailed Implementation

[0020] To make the objectives, technical solutions, and beneficial effects of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. Certain embodiments of the invention will be described more fully below with reference to the accompanying drawings, and some, but not all, of these embodiments will be shown. In fact, various embodiments of the invention can be implemented in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided to enable the invention to meet applicable legal requirements.

[0021] In the description of this invention, it should be noted that the terms "inner," "outer," "upper," "lower," "front," and "rear," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and for 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 this invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0022] In this embodiment of the invention, an equipment and method for testing the impact vibration of an aero-engine fan are provided. Please refer to [reference needed]. Figures 1 to 13 As shown.

[0023] An aero-engine fan shock vibration testing device includes a test chamber 1, a temperature control unit, a launching unit, an angle adjustment unit, and a vibration response pickup unit.

[0024] The test chamber 1 has a sealed cavity 11 inside. The test chamber 1 is used to accommodate and drive the fan test piece 6 to rotate. The test chamber 1 is provided with a launch inlet 12 and an observation window 13 that communicate with the sealed cavity 11.

[0025] The test chamber 1 includes a chamber body 101 and a door 102, which is used to open and close the chamber body 101. The door 102 is opened to facilitate the assembly of the fan test component 6 into the chamber body 101, so that the fan test component 6 is in the sealed cavity 11. The launch inlet 12 and the observation window 13 are located on the door 102.

[0026] A drive motor 14 is installed on one side of the test chamber 1. The output shaft of the drive motor 14 is connected to the fan test piece 6 via the test spindle 15. The drive motor 14 is located outside the test chamber 1, the test spindle 15 passes through the test chamber 1, and the test spindle 15 and the test chamber 1 are connected by a dynamic seal.

[0027] A bearing support frame 151 is installed both inside and outside the test chamber 1. Bearings 152 are installed on the test chamber 1 and the bearing support frame 151. The test spindle 15 is fitted with bearings 152 at both ends and the middle position. The three bearings 152 provide stable support for the test spindle 15, ensuring that the test spindle 15 does not affect the inherent characteristics of the fan test piece 6.

[0028] The fan test piece 6 is assembled onto the test spindle 15, and a clamp 16 is assembled at the end of the test spindle 15 to secure the fan test piece 6.

[0029] A protective frame 17 is installed inside the test chamber 1. The protective frame 17 surrounds the outside of the fan test piece 6 and blocks the fragments of the fan test piece 6 when it is impacted and breaks.

[0030] The test chamber 1 has a light-transmitting window 18 on its housing 101 that communicates with the sealed cavity 11. The light-transmitting window 18 is used to supplement light into the sealed cavity 11 when the vibration response pickup unit (high-speed camera 5) is taking pictures.

[0031] The test chamber 1 has an exhaust port 19 on its housing 101, which communicates with the sealed cavity 11. The exhaust port 19 is connected to an exhaust device via an exhaust pipe. Furthermore, a first pressure sensor is installed inside the sealed cavity 11. The first pressure sensor is connected to a control unit via a signal cable, transmitting real-time pressure data from the sealed cavity 11 to the control unit. The first pressure sensor monitors the pressure inside the sealed cavity 11 in real time. When the pressure inside the sealed cavity 11 exceeds a set value, the exhaust device is activated to bring the pressure inside the sealed cavity 11 back to the set value. This ensures a set pressure difference between the compressed air in the high-pressure airbag 331 and the gas inside the sealed cavity 11, allowing for precise determination of the velocity of the compressed air shock wave.

[0032] The temperature control unit includes a liquid nitrogen injection device, a heating device, and a temperature sensor. The temperature control unit is used to change the temperature inside the sealed cavity 11.

[0033] The top of the test chamber 1 is provided with a liquid nitrogen injection port 21 that communicates with the sealed cavity 11. The liquid nitrogen injection device is connected to the liquid nitrogen injection port 21 via a liquid nitrogen pipeline. The liquid nitrogen injection device injects liquid nitrogen into the sealed cavity 11 via the liquid nitrogen pipeline for cooling and reducing the temperature inside the sealed cavity 11.

[0034] A heating device is disposed within the sealed cavity 11 to raise the temperature within the sealed cavity 11. The heating device is annular, surrounding the fan test piece 6. The annular heating device includes an annular heat insulation layer 221 and multiple electromagnetic heaters 222 arranged at equal intervals on the annular heat insulation layer 221. The annular heating device is located on the annular inner wall of the protective frame 17, which supports the annular heating device. As the fan test piece 6 rotates, the multiple electromagnetic heaters 222 arranged at equal intervals provide uniform heating to the fan test piece 6 and the sealed cavity 11.

[0035] The sensing end of the temperature sensor 23 is located inside the sealed cavity 11 to monitor the temperature inside the sealed cavity 11. The temperature sensor 23 is connected to the control unit via a signal cable to upload the temperature data inside the sealed cavity 11 to the control unit in real time.

[0036] The transmitting unit is connected to the transmitting inlet 12 via the transmitting tube 31. A first solenoid valve 32 is installed between the transmitting unit and the transmitting tube 31. A velocimeter 311, preferably a laser velocimeter, is installed on the transmitting tube 31. The transmitting unit emits a compressed air shock wave, which enters the sealed cavity 11 through the transmitting tube 31 and impacts the rotating fan test piece 6. Specifically, the first solenoid valve 32 is opened to allow the compressed air shock wave to be emitted through the transmitting unit and the transmitting tube 31. The velocimeter 311 monitors the speed of the compressed air shock wave in real time to determine the impact speed of the compressed air shock wave on the fan test piece 6.

[0037] The launching unit includes an air source, a flexible connecting pipe 34, and a soft isolation sleeve 35. The air source is connected to one end of the launching tube 31 via the flexible connecting pipe 34. The air source includes a high-pressure airbag 331 and an air compressor 332. The high-pressure airbag 331 is connected to one end of the launching tube 31 via the flexible connecting pipe 34. The air compressor 332 is connected to the high-pressure airbag 331 via an air supply pipe 36. A second pressure sensor 37 is connected to the air supply pipe 36. The second pressure sensor 37 is connected to the control unit via a signal cable, and uploads the pressure data of the compressed air in the high-pressure airbag 331 to the control unit in real time.

[0038] An exhaust valve 39 is connected to the high-pressure airbag 331, specifically between the high-pressure airbag 331 and the flexible connecting tube 34. When the pressure inside the high-pressure airbag 331 exceeds the set pressure value, some of the compressed air inside the high-pressure airbag 331 is discharged through the exhaust valve 39, so that the pressure inside the high-pressure airbag 331 reaches the set pressure value.

[0039] The second pressure sensor 37 monitors the pressure of the compressed air inside the high-pressure airbag 331 in real time to ensure that the compressed air inside the high-pressure airbag 331 is at a set pressure, thereby determining that the compressed air shock wave emitted from the high-pressure airbag 331 has a set speed, and finally determining that the compressed air shock wave impacts the fan test piece 6 at a set impact speed.

[0040] A second solenoid valve 38 is installed on the air supply pipe 36. After the air compressor 332 fills the high-pressure air bag 331 with compressed gas through the air supply pipe 36 to reach the set pressure, the air supply pipe 36 is shut off by the second solenoid valve 38.

[0041] The soft isolation sleeve 35 is made of a material with heat insulation and resilience. Its configuration is a rotating stepped type. The soft isolation sleeve 35 is filled between the emission inlet 12 and the other end of the emission tube 31. The edge of the soft isolation sleeve 35 is connected to the emission inlet 12 via a flange. An assembly hole 351 is provided in the middle of the soft isolation sleeve 35. The other end of the emission tube 31 is connected to the assembly hole 351.

[0042] By incorporating a soft isolation sleeve 35 and a flexible connecting tube 34, the tilt angle of the transmitting tube 31 can be changed via an angle adjustment unit. The soft isolation sleeve 35 is configured as described above to allow the transmitting tube 31 to tilt at any angle.

[0043] The angle adjustment unit is used to change the tilt angle of the transmitter tube 31, thereby changing the angle at which the compressed air shock wave impacts the fan test piece 6.

[0044] The angle adjustment unit includes a base 41 and a push hydraulic cylinder 42. The fixed end of the push hydraulic cylinder 42 is hinged to the base 41, and the telescopic end of the push hydraulic cylinder 42 is hinged to the launching tube 31. The tilt angle of the launching tube 31 is changed by extending and retracting the telescopic end of the push hydraulic cylinder 42 relative to the fixed end.

[0045] The vibration response acquisition unit is set as a high-speed camera 5, which is used to capture the vibration state of the fan test piece 6 after it is impacted in real time through the observation window 13.

[0046] A method for testing the impact vibration of an aero-engine fan, using the aero-engine fan impact vibration testing equipment described in this embodiment, is as follows: S1. Installation and pressure control; Open the chamber door 102 and fix the fan test piece 6 onto the test spindle 15 using the clamp 16. Close the chamber door 102 to seal the sealed cavity 11. Start the suction device connected to the suction port 19 to evacuate the sealed cavity 11. At the same time, monitor the pressure inside the sealed cavity 11 in real time using the first pressure sensor until the air pressure inside the sealed cavity 11 reaches and stabilizes at the set value.

[0047] S2, drive the fan test piece 6 to rotate; Start the drive motor 14. The drive motor 14 drives the fan test piece 6 to accelerate rotation within the sealed cavity 11 of the test chamber 1 through the test spindle 15 until the fan test piece 6 reaches and stabilizes at the set speed.

[0048] S3. Change the temperature inside the sealed cavity 11 to the set temperature through the temperature adjustment unit; Temperature data within the sealed cavity 11 is monitored in real time by temperature sensor 23. If the temperature of the simulated environment needs to be lowered, the liquid nitrogen injection device is activated via the control unit to inject liquid nitrogen into the sealed cavity 11 for cooling. If the temperature of the simulated environment needs to be raised, the annular heating device is activated, using multiple equally spaced electromagnetic heaters 222 to uniformly heat the rotating fan test piece 6 and the surrounding sealed cavity 11 environment. The cooling capacity or heating power is precisely adjusted using a PID control algorithm to ensure that the temperature within the sealed cavity 11 quickly reaches and stabilizes at the set temperature.

[0049] S4. Impact angle and speed settings; The tilt angle of the launch tube 31 is changed by the angle adjustment unit to alter the angle at which the compressed air shock wave impacts the fan test piece 6. The control unit controls the movement of the push hydraulic cylinder 42 in the angle adjustment unit. The telescopic end of the push hydraulic cylinder 42 pushes or pulls back the launch tube 31. Since the other end of the launch tube 31 is connected to the test chamber 1 and the air source respectively through the soft isolation sleeve 35 and the flexible connecting pipe 34, its tilt angle can be flexibly changed until the axis of the launch tube 31 reaches the preset impact angle with the preset impact point of the fan test piece 6.

[0050] The second pressure sensor 37 monitors the pressure data of the compressed air inside the high-pressure airbag 331 in real time. The air compressor 332 inflates the high-pressure airbag 331 until the pressure inside the high-pressure airbag 331 reaches the set pressure value corresponding to the preset impact speed. When the pressure inside the high-pressure airbag 331 exceeds the set pressure value, some of the compressed air inside the high-pressure airbag 331 is discharged through the exhaust valve 39, so that the pressure inside the high-pressure airbag 331 reaches the set pressure value.

[0051] S5, Shockwave emission and impact; Once preparations are complete, the control unit instantly opens the valve (first solenoid valve 32) to launch a compressed air shock wave through the launching unit. The high-pressure gas inside the high-pressure airbag 331 is released instantaneously, forming a compressed air shock wave. This shock wave passes sequentially through the flexible connecting pipe 34 and the launching pipe 31, finally entering the sealed cavity 11 through the launching inlet 12. As the shock wave passes through the launching pipe 31, the velocimeter 311 on the pipeline monitors and records the actual speed of the compressed air shock wave in real time. The high-speed compressed air shock wave impacts the blades of the rotating fan test piece 6.

[0052] S6. Vibration response acquisition and processing; The vibration response acquisition unit captures the vibration state of the fan test piece 6 after it is impacted in real time, and processes the captured data to obtain the vibration response signal of the fan test piece 6.

[0053] Specifically, at the moment of impact, through observation window 13, a high-speed camera 5 captures and photographs the vibration state (such as blade deformation, vibration modes, etc.) of the fan test piece 6 at an extremely high frame rate in real time, capturing the vibration state of the fan test piece 6 at the instant of impact and within milliseconds thereafter. The high-speed image data captured by the high-speed camera 5 is imported into the analysis system and processed using techniques such as digital image correlation to obtain the vibration response signal of the fan test piece 6 after the impact, including key parameters such as displacement-time curves, strain distribution, vibration frequency, and damping ratio.

[0054] S7. Repeated testing and data recording; Change the set temperature in S3, the impact angle in S4, and / or the set pressure of the high-pressure airbag 331, and repeat the above steps S1-S6 to conduct multiple sets of comparative tests under different working conditions. Record all test data for subsequent analysis of the effects of different temperatures, impact angles, and speeds on the impact vibration characteristics of the fan test piece 6.

[0055] The present invention has been described in detail above with reference to the accompanying drawings. Based on the above description, those skilled in the art should have a clear understanding of the aircraft engine fan impact vibration testing equipment and method of the present invention. Of course, the specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An impact vibration testing device for an aero-engine fan, characterized in that, include: The test chamber has a sealed cavity inside to house and drive the fan test piece to rotate. The test chamber is equipped with a launch inlet and an observation window that communicate with the sealed cavity. Temperature regulation unit, used to change the temperature inside the sealed cavity; The launching unit is connected to the launching inlet via the launching tube. A valve is installed between the launching unit and the launching tube. A speed measuring device is installed on the launching tube. The launching unit emits compressed air shock waves that enter the sealed cavity through the launching tube and impact the rotating fan test piece. An angle adjustment unit is used to change the tilt angle of the transmitter tube, thereby changing the angle at which the compressed air shock wave impacts the fan test piece. The vibration response pickup unit is used to capture the vibration state of the fan test piece after it has been impacted in real time through the observation window.

2. The aero-engine fan impact vibration testing equipment according to claim 1, characterized in that, The temperature regulation unit includes: The test chamber is equipped with a liquid nitrogen injection port that communicates with the sealed cavity. The liquid nitrogen injection device is connected to the liquid nitrogen injection port via a liquid nitrogen pipeline. The liquid nitrogen injection device injects liquid nitrogen into the sealed cavity via the liquid nitrogen pipeline for cooling and reducing the temperature inside the sealed cavity. A heating device is installed inside the sealed cavity to heat and increase the temperature inside the sealed cavity; A temperature sensor, with its sensing end located inside a sealed cavity, is used to monitor the temperature inside the sealed cavity.

3. The aero-engine fan impact vibration testing equipment according to claim 2, characterized in that, The heating device is an annular heating device, which is arranged around the periphery of the fan test piece; the annular heating device includes an annular heat insulation layer and multiple electromagnetic heaters arranged at equal intervals on the annular heat insulation layer.

4. The aero-engine fan impact vibration testing equipment according to claim 1, characterized in that, The launching unit includes a gas source, a flexible connecting pipe, and a soft isolation sleeve; the gas source is connected to one end of the launching tube via the flexible connecting pipe; the soft isolation sleeve is made of a material with heat insulation and resilience, and its configuration is a rotating stepped type. The soft isolation sleeve fills the space between the launching inlet and the other end of the launching tube. The edge of the soft isolation sleeve is connected to the launching inlet, and an assembly hole is provided in the middle of the soft isolation sleeve. The other end of the launching tube is connected to the assembly hole.

5. The aero-engine fan impact vibration testing equipment according to claim 4, characterized in that, The air source includes a high-pressure airbag and an air compressor. The high-pressure airbag is connected to one end of the launch tube via a flexible connecting tube, and the air compressor is connected to the high-pressure airbag via an air supply pipe. A pressure sensor is connected to the high-pressure airbag or the air supply pipe.

6. The aero-engine fan impact vibration testing equipment according to claim 4, characterized in that, The angle adjustment unit includes a base and a pushing hydraulic cylinder. The fixed end of the pushing hydraulic cylinder is hinged to the base, and the telescopic end of the pushing hydraulic cylinder is hinged to the launching tube. The tilt angle of the launching tube is changed by extending and retracting the telescopic end of the pushing hydraulic cylinder relative to the fixed end.

7. The aero-engine fan impact vibration testing equipment according to claim 1, characterized in that, A drive motor is installed on one side of the test box, and the output shaft of the drive motor is connected to the fan test piece via the test spindle.

8. The aero-engine fan impact vibration testing equipment according to claim 1, characterized in that, The test chamber is equipped with a protective frame that surrounds the outside of the fan test piece to prevent fragments from breaking when the fan test piece is impacted.

9. The aero-engine fan impact vibration testing equipment according to claim 1, characterized in that, The test box is equipped with a light-transmitting window that communicates with the sealed cavity. The light-transmitting window is used to supplement light into the sealed cavity when the vibration response pickup unit takes pictures.

10. A method for testing the impact vibration of an aero-engine fan, using the aero-engine fan impact vibration testing equipment according to any one of claims 1 to 9, characterized in that, The method process is as follows: S1. Installation and pressure control; The fan test piece is assembled in the sealed cavity, and the sealed cavity is evacuated. At the same time, the pressure in the sealed cavity is monitored in real time by a pressure sensor until the air pressure in the sealed cavity reaches and stabilizes at the set value. S2, Drive the fan test piece to rotate; The fan test piece is driven to rotate at a set speed within the sealed cavity of the test chamber; S3. Change the temperature inside the sealed cavity 11 to the set temperature through the temperature adjustment unit; S4. Impact angle and speed settings; The angle adjustment unit changes the tilt angle of the transmitter tube to change the angle of the compressed air shock wave to strike the fan test piece at a set angle. The pressure data of compressed air inside the high-pressure airbag is monitored in real time by a pressure sensor. The high-pressure airbag is inflated by an air compressor until the pressure inside the high-pressure airbag reaches the set pressure value corresponding to the preset impact speed. S5, Shockwave emission and impact; The valve is opened instantaneously to emit a compressed air shock wave through the transmitting unit. The actual speed of the compressed air shock wave is monitored and recorded in real time by the speed measuring device. The compressed air shock wave enters the sealed cavity through the transmitting tube and impacts the rotating fan test piece. S6. Vibration response acquisition and processing; The vibration response pickup unit captures and photographs the vibration state of the fan test piece after it is impacted in real time, and processes the captured data to obtain the vibration response signal of the fan test piece. S7. Repeated testing and data recording; Change the set temperature in S3, the impact angle in S4, and / or the set pressure of the high-pressure airbag, and repeat the above steps S1-S6 to conduct multiple sets of comparative tests under different working conditions. Record all test data for subsequent analysis of the effects of different temperatures, impact angles, and speeds on the impact vibration characteristics of the fan test piece.

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