Aero-engine squirrel-cage elastic support damping device design test bench

Abstract

The application discloses a kind of aero-engine squirrel-cage elastic support vibration-damping damper design test bench, including test bench base, squirrel-cage elastic support platform and data acquisition and processing system etc.;Main exciter is installed on the test bench base by main exciter support, side exciter is installed on the test bench base by side exciter support, squirrel-cage elastic support platform is installed on the test bench base, squirrel-cage elastic support platform is equipped with eddy current sensor, magnetic suction acceleration sensor, strain gauge and force sensor.;Data acquisition and processing system includes data acquisition card and computer, the control and data processing of this test bench are sent by computer, the data of force sensor is collected by data acquisition card, the size of exciter exciting force is controlled by controlling the signal of signal generator, and then the response data of squirrel-cage elastic support is recorded by sensor and strain gauge, the data in computer is analyzed, and the dynamics of squirrel-cage elastic support is obtained.

Description

Technical Field

[0001] This invention belongs to the field of damper technology, specifically relating to a design test bench for an elastic support vibration damper for a squirrel cage in an aero-engine. Background Technology

[0002] With the development of high thrust-to-weight ratio and high-speed aero-engines, flexible rotors must pass through critical speeds multiple times during start-up, acceleration, and shutdown, leading to severe rotor vibration. Squirrel-cage elastic supports are typical aero-engine support structures, and their structural characteristics significantly impact the vibration reduction performance of aero-engines. Therefore, a test apparatus for measuring the parameters of squirrel-cage dry friction dampers is of great significance. Traditional squeeze film dampers rely on damping generated by the whirling extrusion of the oil film in the shaft diameter to achieve passive vibration control. However, for aero-engine rotor vibration and noise reduction operating at high speeds, varying conditions, and spanning multiple critical speeds, precise closed-loop control cannot be achieved.

[0003] Dry friction dampers are a common vibration reduction device for engines, widely used in structures such as damping blades and fir-tree blade roots. Currently, dry friction damping is less commonly applied in squeeze film dampers. Patent CN200410073346.0 proposes a rotor vibration testing device with elastic support, controlling damping by adjusting the pressure applied to the moving and stationary friction plates. Patent CN202011197962.2 proposes a compact main-control spring-supported dry friction damper based on a piezoelectric ceramic actuator, solving problems such as the parallelism between the moving and stationary friction plates, the inability to remove debris from the plates, and the easy entry of lubricating oil into the damper. These patents primarily focus on the structure of squirrel-cage dry friction dampers and their application in engine rotor vibration reduction; they do not mention the interface characteristics between the moving and stationary friction plates, which are crucial for vibration control. Summary of the Invention

[0004] The purpose of this invention is to provide a test bench for designing a vibration damping device for an aero-engine squirrel cage elastic support, used to test the interface stiffness and damping characteristics of the moving and stationary friction plates under micro-slip and macro-slip conditions. This test bench can test the interface mechanical parameters under different squirrel cage structures, different friction plate materials, and different contact pressures. The test bench uses a vertically placed elastic support and moving and stationary friction plates, solving the problem of parallelism in the contact between the moving and stationary friction plates. The test bench is excited in two horizontal directions by exciters, which can simulate shaft eddy currents under different frequencies and excitation forces. The response is measured using eddy current sensors to study its vibration reduction characteristics.

[0005] This invention is achieved using the following technical solution:

[0006] A test bench for designing an elastic support vibration damper for a squirrel cage of an aero-engine includes a test bench base, a main exciter support, a main exciter, a side exciter support, a side exciter, a squirrel cage elastic support platform, and a data acquisition and processing system.

[0007] The main exciter is mounted on the test bench base via a main exciter bracket, the side exciter is mounted on the test bench base via a side exciter bracket, the squirrel cage elastic support platform is mounted on the test bench base, and the squirrel cage elastic support platform is equipped with an eddy current sensor, a magnetic accelerometer, a strain gauge and a force sensor.

[0008] The data acquisition and processing system includes a data acquisition card and a computer. The computer controls the test bench and processes the data. The data acquisition card collects data from the force sensor and controls the excitation force of the vibrator by controlling the signal generator. The response data of the squirrel cage elastic support is recorded by the eddy current sensor, the magnetic accelerometer and the strain gauge. The data is then input into the computer for storage. Finally, the data in the computer is analyzed using MATLAB software to obtain the dynamic characteristics of the squirrel cage elastic support.

[0009] A further improvement of the present invention is that an eddy current sensor and a magnetic acceleration sensor are respectively provided in two directions of the main exciter and the side exciter.

[0010] A further improvement of the present invention is that the strain gauge is disposed at the rounded corner inside the elastic support of the squirrel cage.

[0011] A further improvement of the present invention is that the squirrel cage elastic support platform includes a platform left support, a first platform side support, an elastic support mounting base plate, a platform right support, a static friction plate outer frame, a second platform side support, and the internal assembly of the squirrel cage elastic support; the internal assembly of the squirrel cage elastic support includes a static friction plate inner frame, a static friction plate, a dynamic friction plate, and the squirrel cage elastic support.

[0012] When the left and right platform supports are installed, they are kept parallel to the side of the base plate of the squirrel cage elastic support. The first platform side support and the second platform side support are installed on the left and right platform supports respectively. The squirrel cage elastic support is installed on the base plate of the squirrel cage elastic support. The outer frame of the static friction plate is connected to the left platform support, the right platform support, the first platform side support and the second platform side support, and is clearance-fitted with the inner frame of the static friction plate.

[0013] A further improvement of the present invention is that both the left and right supports of the platform maintain a 1mm gap with the side of the elastic support base plate of the mouse cage.

[0014] A further improvement of the present invention is that the main exciter and the side exciter are respectively fixed to the elastic support of the squirrel cage by bolts through the threads on the sleeve exciter rod.

[0015] A further improvement of the present invention is that the force sensor is connected to the sleeved excitation rod and the main exciter via a thread.

[0016] A further improvement of the present invention is that the eddy current sensor is fixed on the outside of the elastic support of the squirrel cage, and the magnetic acceleration sensor is adsorbed on the upper part of the elastic support of the squirrel cage.

[0017] A further improvement of the present invention is that the top of the elastic support of the squirrel cage is connected to the dynamic friction plate through a threaded hole, and the static friction plate is connected to the inner frame of the static friction plate by bolts.

[0018] A further improvement of the present invention is that the outer frame of the static friction plate and the inner frame of the static friction plate are fitted with a clearance, and after the weight is installed, the inner frame of the static friction plate and the outer frame of the static friction plate are locked together by bolts installed through the bolt holes in the middle of the outer frame of the static friction plate.

[0019] The present invention has at least the following beneficial technical effects:

[0020] This invention proposes a test bench for the design of an elastic support vibration damper for aero-engine squirrel cages. This test bench has the following advantages:

[0021] 1. This invention can measure the excitation force and response under elastic support using force sensors and eddy current sensors, and then obtain the frequency response function of the squirrel cage at different frequencies;

[0022] 2. This invention can measure the excitation force and response of the elastic support of the squirrel cage in two vertical directions using a force sensor, an acceleration sensor, and an eddy current sensor, thus simulating the actual eddy current trajectory of the squirrel cage.

[0023] 3. This invention can measure the mechanical properties of the interfacial micro-slip and macro-slip of a rat cage under different pressures by changing the magnitude of the excitation force;

[0024] 4. This invention allows for easy modification of the number and height of the cage ribs to conduct elastic support tests, and enables measurement of the contact characteristics of different materials by replacing the friction pads;

[0025] 5. This invention, through its vertical arrangement and loading devices such as the outer frame of the static friction plate, the inner frame of the static friction plate, and the static friction plate, can ensure the parallelism of the dynamic and static contact. By loading weights of different weights onto the outer frame of the static friction plate, i.e. simulating different magnitudes of normal pressure, the dry friction damping characteristics are obtained through the measurement data of force sensors and eddy current sensors, thereby obtaining optimized parameters for vibration reduction.

[0026] 6. This invention allows for easy replacement of static and dynamic friction plates. By changing parameters such as friction interface material, roughness, and lubrication state, data from force sensors and eddy current sensors can be obtained. Combined with changes in normal pressure parameters, optimal vibration reduction friction parameters can be obtained. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the overall test bench of the present invention;

[0028] Figure 2 This is a schematic diagram of the internal structure of the elastic support mounting platform for the rat cage of the present invention;

[0029] Figure 3 This is an overall internal cross-sectional view of the elastic support mounting platform for the rat cage of the present invention;

[0030] Figure 4 This is a data acquisition schematic diagram of the present invention, taking a force sensor as an example;

[0031] Figure 5 This is a schematic diagram of the sleeved screw of the present invention;

[0032] Figure 6 This is a schematic diagram of an elastic support for a rat cage according to the present invention;

[0033] Figure 7 This is a schematic diagram of the structure of the friction plate of the present invention, wherein... Figure 7 (a) is a moving friction plate. Figure 7 (b) is a static friction plate;

[0034] Figure 8 This is a schematic diagram of the inner frame of the static friction pad of the present invention;

[0035] Figure 9 This is a schematic diagram of the outer frame of the static friction pad of the present invention.

[0036] Explanation of reference numerals in the attached figures:

[0037] 1 is the test bench base, 2 is the main exciter support, 3 is the main exciter, 4 is the side exciter support, 5 is the side exciter, 6 is the left support of the platform, 7 is the side support of the first platform, 8 is the elastic support mounting plate of the squirrel cage, 9 is the right support of the platform, 10 is the outer frame of the static friction plate, 11 is the side support of the second platform, 12 is the inner frame of the static friction plate, 13 is the static friction plate, 14 is the dynamic friction plate, 15 is the elastic support of the squirrel cage, 16 is the eddy current sensor, 17 is the magnetic accelerometer, 18 is the strain gauge, 19 is the force sensor, 20 is the data acquisition card, 21 is the computer, and 22 is the excitation rod with a sleeve. Detailed Implementation

[0038] The present invention will be further described below with reference to the accompanying drawings.

[0039] See Figure 1The present invention provides a test bench for the design of an elastic support vibration damper for a squirrel cage of an aero-engine, including a test bench base 1, a main exciter support 2, a main exciter 3, a side exciter support 4, a side exciter 5, a squirrel cage elastic support platform, and a data acquisition and processing system.

[0040] See Figure 1 , 2 The squirrel cage elastic support platform includes a left platform support 6, a first platform side support 7, an elastic support mounting base plate 8, a right platform support 9, a static friction plate outer frame 10, a second platform side support 11, and the internal assembly of the squirrel cage elastic support; the internal assembly of the squirrel cage elastic support includes a static friction plate inner frame 12, a static friction plate 13, a dynamic friction plate 14, and the squirrel cage elastic support 15. Specifically, the left platform support 6, the right platform support 9, and the squirrel cage elastic support mounting base plate 8 are fixed to the test bench base 1 by T-blocks. The left platform support 7 and the right platform support 9 are installed parallel to the side of the squirrel cage elastic support mounting base plate 8 and are 1mm apart from the side of the squirrel cage elastic support mounting base plate 8. The first platform side support 7 and the second platform side support 11 are respectively bolted to the left platform support 6 and the right platform support 8. The squirrel cage elastic support 15 is installed on the squirrel cage elastic support mounting base plate 8. The static friction plate outer frame 10 is bolted to the left platform support 6, the right platform support 9, the first platform side support 7, and the second platform side support 11 and is clearance-fitted with the static friction plate inner frame 12. The main exciter 3 and the side exciter 5 are bolted to the squirrel cage elastic support 15 through the threads on the sleeve exciter rod 22 to ensure that the excitation force acts on the squirrel cage elastic support, thereby simulating the actual movement of the elastic support.

[0041] See Figure 2 , 3 An eddy current sensor 16 is fixed to the outside of the squirrel cage elastic support 15, a magnetic accelerometer 17 is attached to the upper part of the squirrel cage elastic support 15, and a strain gauge 18 is attached to the stress concentration area of ​​the squirrel cage elastic support 15. The displacement of the squirrel cage and the static friction disk is measured by the eddy current sensor 16 and the magnetic accelerometer 17, achieving accurate measurement of the relative displacement and relative velocity at the interface. The strain level of the squirrel cage is measured by the strain gauge 18, providing experimental data for the life analysis of the squirrel cage elastic support.

[0042] See Figure 5 , 6 7. The top of the squirrel cage elastic support 15 is connected to the dynamic friction plate 14 through a threaded hole, which facilitates the replacement of the dynamic friction plate 14. The static friction plate 13 is connected to the static friction plate inner frame 12 by bolts, which facilitates the replacement of the static friction plate 13.

[0043] See Figure 8The outer frame 10 of the static friction plate and the inner frame 12 of the static friction plate are fitted with a clearance. After the weight is installed, the inner frame 12 of the static friction plate is locked to the outer frame 14 by bolts installed through the bolt holes in the middle of the outer frame 10. Different masses of weights can be loaded on top of the inner frame 12 of the static friction plate. By changing the mass of the weights, the magnitude of the normal pressure applied by the static friction plate 13 to the dynamic friction plate 14 can be changed.

[0044] The materials of the dynamic friction plate 14 and the static friction plate 13 can be replaced to test and analyze the mechanical behavior of different material interfaces.

[0045] In this invention, the overall control and data processing are all controlled by computer 21. Specifically, data from force sensor 19 is acquired through data acquisition card 20. Force sensor 19 has an M5 thread and is connected to the sleeve-type excitation rod 22 and the main exciter 3 via the thread. Computer 21 controls the magnitude of the excitation force of the exciter, and then the response data of the squirrel cage elastic support is recorded by acquisition devices such as eddy current sensor 16, magnetic accelerometer 17, and strain gauge 18. The data is then input into the computer for storage via data acquisition device. Finally, the displacement data of eddy current sensor 16 and the excitation force data of force sensor 19 stored in computer 21 are post-processed to obtain the dynamic characteristics of squirrel cage elastic support.

[0046] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A test bench for designing an elastic support vibration damper for a squirrel cage in an aero-engine, characterized in that, It includes a test bench base, a main exciter support, a main exciter, a side exciter support, a side exciter, a squirrel cage elastic support platform, and a data acquisition and processing system; The main exciter is mounted on the test bench base via a main exciter bracket, the side exciter is mounted on the test bench base via a side exciter bracket, the squirrel cage elastic support platform is mounted on the test bench base, and the squirrel cage elastic support platform is equipped with an eddy current sensor, a magnetic accelerometer, a strain gauge and a force sensor. The data acquisition and processing system includes a data acquisition card and a computer. The computer controls the test bench and processes the data. The data acquisition card collects data from the force sensor and controls the signal generator to control the excitation force of the vibrator. The response data of the squirrel cage elastic support is recorded by the eddy current sensor, the magnetic accelerometer and the strain gauge. The data is then input into the computer for storage. Finally, MATLAB software is used to analyze the data in the computer to obtain the dynamic characteristics of the squirrel cage elastic support. Both the eddy current sensor and the magnetic accelerometer are installed in two directions, one in each of the main exciter and the side exciter. The squirrel cage elastic support platform includes a left platform support, a first platform side support, an elastic support mounting base plate, a right platform support, a static friction plate outer frame, a second platform side support, and the internal assembly of the squirrel cage elastic support; the internal assembly of the squirrel cage elastic support includes a static friction plate inner frame, static friction plates, dynamic friction plates, and the squirrel cage elastic support. When the left and right platform supports are installed, they are kept parallel to the side of the base plate of the squirrel cage elastic support. The first platform side support and the second platform side support are installed on the left and right platform supports respectively. The squirrel cage elastic support is installed on the base plate of the squirrel cage elastic support. The outer frame of the static friction plate is connected to the left platform support, the right platform support, the first platform side support and the second platform side support, and is clearance-fitted with the inner frame of the static friction plate.

2. The test bench for designing an elastic support vibration damper for a squirrel cage of an aero-engine according to claim 1, characterized in that, The strain gauges are installed at the rounded corners inside the elastic support of the squirrel cage.

3. The test bench for designing an elastic support vibration damper for a squirrel cage of an aero-engine according to claim 1, characterized in that, Both the left and right supports of the platform maintain a 1mm gap from the side of the elastic support base plate of the rat cage.

4. The test bench for designing an elastic support vibration damper for a squirrel cage of an aero-engine according to claim 1, characterized in that, The main exciter and the side exciter are respectively fixed to the squirrel cage elastic support by bolts through the threads on the sleeve exciter rod.

5. The test bench for designing an elastic support vibration damper for a squirrel cage of an aero-engine according to claim 4, characterized in that, The force sensor is connected to the sleeved exciter rod and the main exciter via threads.

6. The test bench for designing an elastic support vibration damper for a squirrel cage of an aero-engine according to claim 1, characterized in that, The eddy current sensor is fixed to the outside of the elastic support of the squirrel cage, and the magnetic accelerometer is attached to the upper part of the elastic support of the squirrel cage.

7. The test bench for designing an elastic support vibration damper for a squirrel cage of an aero-engine according to claim 1, characterized in that, The top of the squirrel cage elastic support is connected to the dynamic friction plate through a threaded hole, and the static friction plate is connected to the inner frame of the static friction plate by bolts.

8. The test bench for designing an elastic support vibration damper for a squirrel cage of an aero-engine according to claim 1, characterized in that, The outer frame of the static friction plate and the inner frame of the static friction plate are fitted with a clearance. After the heavy object is installed, the inner frame of the static friction plate and the outer frame of the static friction plate are locked together by installing bolts through the bolt holes in the middle of the outer frame of the static friction plate.

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