A test device for the vibration suppression effect of a squeeze film damper

Abstract

The present application belongs to the field of engine testing technology, and specifically relates to a vibration suppression effect test device for a squeeze film damper. The device comprises a rotor shaft (7), the first end of which is supported by a first support (11) and a second support (12), and the second end is supported by a third support (13); a cantilever disk fixed to the first end of the rotor shaft (7) for simulating a power turbine disk; an elastic support (6), which comprises a ring plate (61) and a support arm (62), the inner end of the ring plate (61) being rotatably connected to the rotor shaft (7), an oil film cavity (63) being formed between the outer end of the ring plate (61) and the first support (11), and the support arm (62) being connected to the second support (12); the first support (11) being a height-adjustable support, and having a through hole thereon that penetrates the oil film cavity (63). The present application achieves similarity with actual structure and dynamics, and can carry out real-size vibration suppression effect test research for a squeeze film damper.

Description

Technical Field

[0001] The present application belongs to the technical field of engine testing, and in particular relates to a device for testing the vibration suppression effect of a squeeze film damper. Background Art

[0002] The vibration of aircraft engines and aero-derivative gas turbines directly impacts their lifespan and safety. Statistics show that over 90% of structural strength failures are caused by or related to vibration. Aircraft and gas turbines are complex structures and operate in harsh conditions, and numerous factors can influence overall vibration. The most effective method for reducing engine vibration and improving stability is to employ a spring-loaded damper structure. A spring-loaded damper uses an elastic structure to support the rotor shaft. This structure also forms oil film holes with the engine casing, which are then injected with oil to provide vibration damping. Therefore, the invention of a rotor system vibration test device to study the vibration suppression effect of a squeeze film damper is of high engineering significance.

[0003] Existing research mainly focuses on small-scale test devices, without considering structural and dynamic similarity. The test results have little engineering significance, and generally fail to consider the effects of initial eccentricity and pre-adjusted concentricity, making it impossible to complete such experimental research. Its main shortcomings are:

[0004] 1) Neither approach achieved structural or dynamic similarity with the actual structure. Given the structural dimensions, the vibration suppression results obtained on a small, scaled-down test rig offer limited application value for a structure like a squeeze film damper, which exhibits highly dynamic nonlinearities. Furthermore, the lack of consideration for dynamic similarity in the rotor test rig itself deviates from the potential for direct engineering application.

[0005] 2) The existing technical solutions do not take into account the effects of the initial eccentricity and pre-adjusted concentricity of the damper under rotor gravity conditions, and cannot implement relevant experimental research. Summary of the Invention

[0006] In order to solve one of the above problems, the present application provides a vibration suppression effect test device for a squeeze film damper, which mainly includes:

[0007] The rotor shaft comprises a first end and a second end, wherein the first end is rotatably supported by a first support and a second support, the second end is rotatably supported by a third support, and the second end is connected to a power input device via a coupling;

[0008] a cantilever disk fixed to the first end of the rotor shaft to simulate a power turbine disk;

[0009] An elastic support comprises a ring plate and a plurality of support arms distributed along the circumference of the ring plate. The inner end of the ring plate is rotatably connected to the rotor shaft, and an oil film cavity is formed between the outer end of the ring plate and the first support. The support arms extend in a direction parallel to the axial direction of the ring plate, with one end connected to the outer end of the ring plate and the other end connected to the second support.

[0010] The first support is a height-adjustable support. The first support is provided with a through hole penetrating the oil film cavity. The oil film cavity is connected to the oil supply system via the through hole.

[0011] Preferably, the elastic support is connected to the rotor shaft via a first deep groove ball bearing.

[0012] Preferably, the third support has a bearing seat and is connected to the rotor shaft via a second deep groove ball bearing.

[0013] Preferably, the cantilever disk includes a first cantilever disk and a second cantilever disk, and the two cantilever disks are coaxially mounted on the first end of the rotor shaft.

[0014] Preferably, the first cantilever disk is sleeved on the rotor shaft, and a first conical sleeve is provided between it and the outer wall of the rotor shaft, an outer annular wall is provided at one end of the thick wall of the first conical sleeve, and the outer annular wall of the first conical sleeve and the first cantilever disk are tightened by a tightening bolt.

[0015] Preferably, the second cantilever disk is sleeved on the rotor shaft, and a second conical sleeve is provided between it and the outer wall of the rotor shaft, an outer annular wall is provided at one end of the thick wall of the first conical sleeve, and the outer annular wall of the second conical sleeve and the second cantilever disk are tightened by a tightening bolt.

[0016] Preferably, the cantilever disk is provided with a plurality of bolt holes arranged along the circumferential direction, and the imbalance of the cantilever disk is adjusted by installing counterweight bolts of an appropriate number or weight.

[0017] Preferably, it further comprises a plurality of gaskets, through which the height of the first support is adjusted.

[0018] The invention of this application is:

[0019] Similar structure: This test device simulates the power turbine structure of a gas turbine and adopts a two-point rotor structure with a cantilever disk. The cantilever disk (with an unbalanced loading structure) is used to simulate the multi-stage power turbine structure. A squirrel cage spring support and a squeeze film damper structure are set at the support point near the end of the cantilever disk. The size of the spring support-damper structure is the same as the actual size, and the rigid support is used to provide stable support for the rotor system.

[0020] Dynamic similarity: Taking the dynamic characteristics of a gas turbine power turbine rotor as the target, by adjusting the test device's support span, shaft segment inner and outer diameters, and cantilever disk mass parameters, it is possible to ensure that the critical speed of the first-order cantilever end pitching vibration mode exists within the test device's operating speed range. The errors of the critical speed and support strain energy are both within 10%.

[0021] Oil film eccentricity adjustment: The rigid support of the squeeze film damper's outer ring is adjustable vertically and horizontally, allowing for consideration of initial eccentricity and pre-adjusted concentricity. The oil film gap can be directly measured, ensuring accurate adjustment.

[0022] The advantages of this application are:

[0023] The test device achieves similarity with the actual structure and dynamics, and can carry out real-size test research on the vibration suppression effect of squeeze film dampers. It has the ability to test the vibration suppression effect of dampers taking into account the effects of initial eccentricity and pre-adjusted concentricity. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the overall device of a preferred embodiment of the vibration suppression effect test device of the squeeze film damper of the present application.

[0025] Figure 2 For this application Figure 1 Schematic diagram of the internal structure of the embodiment shown.

[0026] Figure 3 For this application Figure 1 Schematic diagram of the external structure of the embodiment shown.

[0027] Figure 4 For this application Figure 1 Schematic diagram of the cantilever disc bolt holes for the illustrated embodiment.

[0028] Figure 5 For this application Figure 1 Schematic diagram of an oil film cavity formed between the elastic support and the first support in the illustrated embodiment.

[0029] Among them, 1-first tapered sleeve, 2-first cantilever disk, 3-second tapered sleeve, 4-second cantilever disk, 5-first deep groove ball bearing, 6-elastic support, 61-ring plate, 62-support arm, 63-oil film cavity, 7-rotor shaft, 8-bearing seat, 9-second deep groove ball bearing, 10-coupling, 11-first support, 12-second support, 13-third support, 14-bolt hole. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the implementation of this application clearer, the technical solutions in the implementation of this application will be described in more detail below in conjunction with the drawings in the implementation of this application. In the drawings, the same or similar numbers throughout represent the same or similar elements or elements with the same or similar functions. The described implementation is a part of the implementation of this application, not all of the implementations. The implementation described below with reference to the drawings is exemplary and is intended to be used to explain this application, and should not be understood as a limitation on this application. Based on the implementation in this application, all other implementations obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. The implementation of this application is described in detail below in conjunction with the drawings.

[0031] The present application provides a vibration suppression effect test device for a squeeze film damper, such as Figure 1-Figure 5 As shown, it mainly includes:

[0032] The rotor shaft 7 includes a first end and a second end, wherein the first end is rotatably supported by a first support 11 and a second support 12, and the second end is rotatably supported by a third support 13, and the second end is connected to the power input device via a coupling 10;

[0033] a cantilever disk, fixed to the first end of the rotor shaft 7, for simulating a power turbine disk;

[0034] The elastic support 6 includes a ring plate 61 and a plurality of support arms 62 distributed circumferentially along the ring plate 61. The inner end of the ring plate 61 is rotatably connected to the rotor shaft 7. An oil film cavity 63 is formed between the outer end of the ring plate 61 and the first support 11. The support arms 62 extend in a direction parallel to the axis of the ring plate 61, with one end connected to the outer end of the ring plate 61 and the other end connected to the second support 12.

[0035] The first support 11 is a height-adjustable support. The first support 11 has a through hole penetrating the oil film cavity 63 . The oil film cavity 63 is connected to the oil supply system via the through hole.

[0036] refer to Figure 1 、 Figure 2 and Figure 3 , install the three supports of the test device on a stable ground foundation, and complete the assembly of the spring-loaded support structure, bearings, and rotor system. Flexibly connect the input coupling to the device's power source to minimize the mechanical properties of "torque transmission without bending." Connect the damper's oil inlet and outlet holes on the first support 11, which are connected to the oil film cavity, to the oil supply system. Install speed and vibration measurement sensors according to the specific test requirements to complete the test system commissioning.

[0037] Specifically, when conducting the dynamic characteristics similarity verification test, the critical speed of the pitch vibration mode of the cantilever end is identified through a slow speed sweep test combined with the vibration performance, so that the error between the identified critical speed and the critical speed of the turbine rotor of a certain gas engine is within 10%. If the error requirement is not met, the position of the third support 13 is adjusted to ensure the similarity of the dynamic characteristics.

[0038] refer to Figure 5 Injecting oil into the oil film cavity 63 through the through hole allows for research on the impact of the damper's oil supply and discharge pressures on vibration damping. This can be achieved by adjusting the oil supply system's supply and discharge pressures. Vibration measurements can reveal the influence of vibration suppression. Furthermore, injecting oil into the oil film cavity 63 through the through hole also allows for research on the impact of lubricating oil viscosity, which can be achieved by adjusting the oil temperature or replacing the lubricating oil.

[0039] In some optional embodiments, the elastic support 6 is connected to the rotor shaft 7 via a first deep groove ball bearing 5 .

[0040] In some optional embodiments, the third support 13 has a bearing seat 8 and is connected to the rotor shaft 7 via a second deep groove ball bearing 9 .

[0041] In some optional embodiments, the cantilever disk includes a first cantilever disk 2 and a second cantilever disk 4 , and the two cantilever disks are coaxially mounted on the first end of the rotor shaft 7 .

[0042] In some optional embodiments, reference Figure 2 The first cantilever disk 2 is sleeved on the rotor shaft 7, and a first conical sleeve 1 is arranged between it and the outer wall of the rotor shaft 7. An outer ring wall is arranged at one end of the thick wall of the first conical sleeve 1, and the outer ring wall of the first conical sleeve 1 and the first cantilever disk 2 are tightened by a tightening bolt.

[0043] In some optional embodiments, reference Figure 2 The second cantilever disk 4 is sleeved on the rotor shaft 7, and a second conical sleeve 3 is arranged between it and the outer wall of the rotor shaft 7. An outer annular wall is arranged at one end of the thick wall of the first conical sleeve 3, and the outer annular wall of the second conical sleeve 3 and the second cantilever disk 4 are tightened by a tightening bolt.

[0044] In some optional embodiments, reference Figure 4 The cantilever disk is provided with a plurality of bolt holes 14 arranged along the circumferential direction, and the imbalance of the cantilever disk is adjusted by installing counterweight bolts of an appropriate number or weight.

[0045] The test device can load and adjust the rotor imbalance by installing counterweight bolts of different numbers or weights through the balance bolt holes 14 reserved on the first cantilever disk 2 and the second cantilever disk 4.

[0046] In some optional embodiments, the test apparatus further includes a plurality of shims, which are used to adjust the height of the first support 11. By adjusting the height of the first support 11, the effects of oil film eccentricity and pre-adjusted concentricity of the elastic support-damper can be studied. The height adjustment can be achieved by adjusting the thickness of the shims between the first support 11 and the mounting base. The oil film thickness between the elastic support 6 and the first support 11 can be directly measured (using a feeler gauge or a higher-precision measurement method), ensuring test accuracy.

[0047] The test device of the present application has characteristics similar to the actual structure and dynamics, and can carry out real-size test research on the vibration suppression effect of the squeeze film damper. The test results directly correspond to the performance of the real elastic strut-damper on the gas turbine and can be directly applied to engineering, avoiding the inevitable errors when converting the research results obtained based on the scaled tester into engineering applications.

[0048] This application has the ability to test the vibration suppression effect of the damper taking into account the influence of initial eccentricity and pre-adjusted concentricity, solving the technical difficulty that such problems cannot be obtained through testing.

[0049] The reasonable damper parameters obtained by applying this test device to the gas turbine can significantly reduce the vibration of the power turbine rotor and improve the reliability of the gas turbine.

[0050] Although the present application has been described in detail above using general descriptions and specific embodiments, it will be apparent to those skilled in the art that modifications or improvements may be made based on the present application. Therefore, such modifications or improvements, which do not depart from the spirit of the present application, are within the scope of protection claimed in the present application.

Claims

1. A vibration suppression effect test device for a squeeze film damper, characterized in that: include: The rotor shaft (7) comprises a first end and a second end, wherein the first end is rotatably supported by a first support (11) and a second support (12), and the second end is rotatably supported by a third support (13), and the second end is connected to a power input device via a coupling (10); a cantilever disk fixed to a first end of the rotor shaft (7) for simulating a power turbine disk; An elastic support (6) includes a ring plate (61) and a plurality of support arms (62) distributed along the circumference of the ring plate (61), wherein the inner end of the ring plate (61) is rotatably connected to the rotor shaft (7), an oil film cavity (63) is formed between the outer end of the ring plate (61) and the first support (11), and the support arm (62) extends in a direction parallel to the axial direction of the ring plate (61), one end of which is connected to the outer end of the ring plate (61) and the other end is connected to the second support (12); The first support (11) is a height-adjustable support, and the first support (11) has a through hole penetrating the oil film cavity (63), and the oil film cavity (63) is connected to the oil supply system through the through hole; The cantilever disk comprises a first cantilever disk (2) and a second cantilever disk (4), and the two cantilever disks are coaxially mounted on the first end of the rotor shaft (7); the cantilever disk is provided with a plurality of bolt holes (14) arranged along the circumference, and the unbalance of the cantilever disk is adjusted by installing counterweight bolts of an appropriate number or weight.

2. The vibration suppression effect test device of a squeeze film damper according to claim 1, characterized in that: The elastic support (6) is connected to the rotor shaft (7) via a first deep groove ball bearing (5).

3. The vibration suppression effect test device of a squeeze film damper according to claim 1, characterized in that: The third support (13) has a bearing seat (8) and is connected to the rotor shaft (7) via a second deep groove ball bearing (9).

4. The vibration suppression effect test device of a squeeze film damper according to claim 1, characterized in that: The first cantilever disc (2) is sleeved on the rotor shaft (7), and a first cone sleeve (1) is provided between the first cantilever disc and the outer wall of the rotor shaft (7). An outer ring wall is provided at one end of the wall thickness of the first cone sleeve (1), and the outer ring wall of the first cone sleeve (1) and the first cantilever disc (2) are tightened by a tightening bolt.

5. The vibration suppression effect test device of a squeeze film damper according to claim 1, characterized in that: The second cantilever disc (4) is sleeved on the rotor shaft (7), and a second cone sleeve (3) is provided between the second cantilever disc and the outer wall of the rotor shaft (7). An outer ring wall is provided at one end of the wall thickness of the second cone sleeve (3), and the outer ring wall of the second cone sleeve (3) and the second cantilever disc (4) are tightened by a tightening bolt.

6. The vibration suppression effect test device of a squeeze film damper according to claim 1, characterized in that: It also includes a plurality of gaskets, through which the height of the first support (11) is adjusted.

Images