CN214407995U - Testing device for damping effect of squeeze film damper - Google Patents
Testing device for damping effect of squeeze film damper Download PDFInfo
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- CN214407995U CN214407995U CN202120414541.4U CN202120414541U CN214407995U CN 214407995 U CN214407995 U CN 214407995U CN 202120414541 U CN202120414541 U CN 202120414541U CN 214407995 U CN214407995 U CN 214407995U
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- film damper
- inner ring
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Abstract
The utility model relates to a testing arrangement of squeeze film damper damping effect for alleviate the problem of damping effect test difficulty. Wherein, testing arrangement of squeeze film damper damping effect includes: a support; the rotor is rotatably arranged on the bracket; the squeeze film damper comprises an inner ring and an outer ring, the inner ring is connected to the rotor, and the outer ring is arranged on the periphery of the inner ring and connected to the support; and a plurality of adjusting components arranged at intervals along the circumferential direction of the outer ring and configured to adjust the concentricity of the outer ring and the inner ring and adjust the gap between the outer ring and the inner ring. The utility model discloses can finely tune the concentricity under the condition of not dismantling squeeze film damper, improve the accuracy of test result, and the test is convenient.
Description
Technical Field
The utility model relates to a measuring device field especially relates to a testing arrangement of squeeze film damper damping effect.
Background
The rotating speed of the rotor of the aircraft engine is usually set above the critical rotating speed of the rotor, the rotor needs to frequently pass the critical rotating speed in the starting and stopping process, the vibration magnitude of the rotor when the rotor passes the critical rotating speed is influenced by the load (unbalance amount and the like) and also influenced by damping, the vibration response of the rotor when the rotor passes the critical rotating speed can be reduced by increasing the damping of a rotor system under the general condition, therefore, an extrusion oil film damper is often arranged at the bearing of the rotor to increase the damping of the rotor system, reduce the vibration amplitude of the rotor when the rotor passes the critical rotating speed and avoid the overlarge vibration of the rotor.
The damping value of the squeeze film damper cannot be too small, otherwise the vibration of the rotor when the rotor passes through the critical rotating speed cannot be reduced; however, the damping value of the squeeze film damper needs to be controlled within a range, which cannot be too large, and when the damping value is too large, other problems are caused, and the vibration of the rotor is increased, so that the actual optimal value of the damper needs to be measured and controlled.
The damping effect of the squeeze film damper is related to the use conditions such as the use temperature and the oil supply pressure, and is also related to the size of the oil film radius gap, the length of the oil film along the axial direction, the oil supply structure form of the oil film, the end seal structure of the oil film and other specific structures, and factors influencing the damping effect are more, so that the difficulty is brought to the damping measurement of the squeeze film damper.
Disclosure of Invention
Some embodiments of the utility model provide a testing arrangement of squeeze film damper damping effect for alleviate the problem of damping effect test difficulty.
Some embodiments of the utility model provide a testing arrangement of squeeze film damper damping effect, it includes:
a support;
the rotor is rotatably arranged on the bracket;
the squeeze film damper comprises an inner ring and an outer ring, the inner ring is connected to the rotor, and the outer ring is arranged on the periphery of the inner ring and connected to the support; and
a plurality of adjustment assemblies disposed at intervals along a circumferential direction of the outer ring and configured to adjust concentricity of the outer ring and the inner ring and adjust a gap between the outer ring and the inner ring.
In some embodiments, each of the plurality of adjustment assemblies includes a first adjustment member and a second adjustment member that are perpendicular to each other, wherein the first adjustment member is configured to adjust the position of the outer ring in the vertical direction and the second adjustment member is configured to adjust the position of the outer ring in the horizontal direction.
In some embodiments, the first adjusting member includes a first screw penetrating through the bracket and abutting against the outer ring, and/or the second adjusting member includes a second screw penetrating through the bracket and abutting against the outer ring.
In some embodiments, the outer ring is configured to be removably secured to the bracket.
In some embodiments, the inner ring is configured to be removably disposed to the rotor.
In some embodiments, the device for testing the damping effect of the squeeze film damper further comprises a bearing and an elastic support, wherein the bearing is arranged at the end part of the rotor, the elastic support is arranged at the periphery of the bearing, and the inner ring is arranged at the periphery of the elastic support.
In some embodiments, the device for testing the damping effect of a squeeze film damper further comprises a nut disposed at the outer periphery of the elastic support and configured to abut the inner ring.
In some embodiments, first grooves are respectively formed at two ends of the inner ring along the axial direction of the rotor, and an oil supply channel is formed in the outer ring and is communicated with a gap between the inner ring and the outer ring between the two first grooves.
In some embodiments, two ends of the inner ring are respectively provided with a first groove along the axial direction of the rotor, the inner ring is further provided with a second groove, the second groove is located between the two first grooves, the outer ring is provided with an oil supply channel, and the oil supply channel is communicated with the second groove.
In some embodiments, the device for testing the damping effect of a squeeze film damper further comprises a weight member configured to be detachably provided to the rotor to adjust the unbalance amount of the rotor.
Based on the technical scheme, the utility model discloses following beneficial effect has at least:
in some embodiments, the rotor provided with the squeeze film damper can be rotatably arranged on the support, the plurality of adjusting assemblies are arranged at intervals along the circumferential direction of the outer ring, the concentricity of the outer ring and the inner ring of the squeeze film damper is adjusted through the adjusting assemblies, the gap between the outer ring and the inner ring is adjusted, the concentricity can be finely adjusted under the condition that the squeeze film damper is not detached, the accuracy of a test result is improved, and the test is convenient.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without undue limitation to the invention. In the drawings:
fig. 1 is a schematic front view of a device for testing damping effect of a squeeze film damper according to some embodiments of the present invention;
fig. 2 is a schematic side view of a device for testing damping effect of a squeeze film damper according to some embodiments of the present invention;
fig. 3 is a schematic view of the inner ring and the outer ring provided according to the first embodiment of the present invention;
FIG. 4 is an enlarged partial schematic view of FIG. 3;
fig. 5 is a schematic view of the inner ring and the outer ring according to the second embodiment of the present invention;
fig. 6 is a diagram illustrating the damping effect measured by the testing device according to some embodiments of the present invention under a certain unbalance amount, wherein the horizontal axis represents the rotation speed and the vertical axis represents the amplitude.
The reference numbers in the drawings illustrate the following:
1-a scaffold; 11-a first support; 12-a second support;
2-a rotor;
3-squeeze film dampers; 31-inner ring; 311-a first groove; 312 — a second groove; 32-outer ring; 321-an oil supply channel;
4-a regulating component; 41-a first adjustment member; 42-a second adjustment member;
5-a bearing;
6-elastic support;
7-a nut;
8-bolt;
9-coupler.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. It is obvious that the described embodiments are only some of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by a person of ordinary skill in the art without creative efforts belong to the protection scope of the present invention.
In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element so referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be taken as limiting the scope of the invention.
Critical speed (critical speed): the rotor vibrates strongly during the lifting and lowering operations at certain rotational speeds, which are generally referred to as critical rotational speeds.
As shown in fig. 1, some embodiments provide a test device for the damping effect of a squeeze film damper, which includes a bracket 1, a rotor 2, a squeeze film damper 3, and a plurality of adjustment assemblies 4.
Optionally, the stand 1 comprises a first abutment 11 and a second abutment 12.
The rotor 2 is rotatably provided to the bracket 1.
Alternatively, a first end of the rotor 2 is supported by a first support 11 and a second end of the rotor 2 is supported by a second support 12.
The squeeze film damper 3 includes an inner ring 31 and an outer ring 32, the inner ring 31 being connected to the rotor 2, and the outer ring 32 being provided on the outer periphery of the inner ring 31 and connected to the bracket 1.
Optionally, a squeeze film damper 3 is provided at a first end of the rotor 2. The second end of the rotor 2 is connected to the motor, optionally, the second end of the rotor 2 is provided with a coupling 9, and the second end of the rotor 2 is connected to the output shaft of the motor through the coupling 9.
A plurality of adjustment assemblies 4 are provided at intervals along the circumferential direction of the outer ring 32, and are configured to adjust the concentricity of the outer ring 32 and the inner ring 31, and to adjust the gap between the outer ring 32 and the inner ring 31.
Alternatively, the number of the plurality of adjustment assemblies 4 is four, and four adjustment assemblies 4 are arranged at regular intervals in the circumferential direction of the outer ring 32.
In some embodiments, the rotor 2 with the squeeze film damper 3 can be rotatably arranged on the bracket 1, the plurality of adjusting assemblies 4 are arranged at intervals along the circumferential direction of the outer ring 32, the concentricity of the outer ring 32 and the inner ring 31 is adjusted through the adjusting assemblies 4, and the gap between the outer ring 32 and the inner ring 31 is adjusted, so that the concentricity can be finely adjusted under the condition that the squeeze film damper 3 is not detached, the accuracy of a test result is improved, and the damping effect is convenient to measure.
In some embodiments, the device for testing the damping effect of a squeeze film damper further comprises a sensor configured to measure the vibration of the rotor 2 for evaluating the damping effect of the squeeze film damper 3.
In some embodiments, as shown in fig. 2, each adjustment assembly 4 of the plurality of adjustment assemblies 4 includes a first adjustment member 41 and a second adjustment member 42 that are perpendicular to each other, wherein the first adjustment member 41 is configured to adjust the position of the outer ring 32 in the vertical direction, and the second adjustment member 42 is configured to adjust the position of the outer ring 32 in the horizontal direction.
In some embodiments, the first adjusting member 41 includes a first screw, which is disposed through the bracket 1 and abuts against the outer ring 32.
In some embodiments, the second adjusting member 42 includes a second screw, which is inserted through the bracket 1 and abuts against the outer ring 32.
In some embodiments, the outer ring 32 is configured to be removably disposed on the stent 1.
Alternatively, the outer ring 32 is detachably connected to the bracket 1 by means of bolts 8. When the concentricity and the clearance between the outer ring 32 and the inner ring 31 are adjusted, the bolt 8 can be firstly unscrewed, the clearance between the outer ring 32 and the inner ring 31 of the squeeze film damper 3 is adjusted by adjusting the first adjusting piece 41 in the vertical direction and the second adjusting piece 42 in the horizontal direction, the circumferential clearance between the outer ring 32 and the inner ring 31 can be uniform, a static eccentricity can also be preset, and the bolt 8 is screwed after the adjustment is finished.
In some embodiments, the inner ring 31 is configured to be removably attached to the rotor 2, which allows to adjust the structural parameters of the squeeze film damper 3 without disassembling the rotor 2, without disassembling the main support, for example: different oil film radiuses and/or different oil film oil feeding groove structures and the like reduce the workload of disassembly and assembly, and reduce the debugging work such as centering and dynamic balance of the rotor 2.
In some embodiments, the testing device for the damping effect of the squeeze film damper further comprises a bearing 5 and an elastic support 6, wherein the bearing 5 is arranged at the end part of the rotor 2, the elastic support 6 is arranged at the outer periphery of the bearing 5, and the inner ring 31 is arranged at the outer periphery of the elastic support.
Optionally, the elastic support 6 comprises a squirrel cage elastic support.
In some embodiments, the device for testing the damping effect of a squeeze film damper further comprises a nut 7, the nut 7 being provided at the outer periphery of the elastic support 6, and the nut 7 being configured to abut against the inner ring 31. The position of the inner ring 31 is locked by the nut 7, and the inner ring 31 is prevented from falling off the elastic support 6.
In some embodiments, as shown in fig. 3 and 4, the inner ring 31 is provided with first grooves 311 at both ends thereof, the inner ring 31 is further provided with second grooves 312, the second grooves 312 are located between the two first grooves 311, and the outer ring 32 is provided with oil supply passages 321, wherein the oil supply passages 321 are communicated with the second grooves 312 along the axial direction of the rotor 2.
In some embodiments, as shown in fig. 5, the inner ring 31 is provided with first grooves 311 at both ends thereof, and the outer ring 32 is provided with an oil supply passage 321, respectively, along the axial direction of the rotor 2, and the oil supply passage 321 communicates with a gap between the inner ring 31 and the outer ring 32 between the two first grooves 311.
The distance between the two first grooves 311 is the axial length L of the oil film between the inner ring 31 and the outer ring 32, and the two first grooves 311 are in an oil film end seal structure. The gap S between the inner ring 31 and the outer ring 32 is an oil film radius gap S.
In some embodiments, a method of adjusting a structural parameter of a squeeze film damper includes: the nut 8 and the inner ring 31 of the squeeze film damper are disassembled, the new inner ring 31 of the squeeze film damper is replaced and locked by the nut 8, and the adjustable structural parameters of the damper comprise an oil film radius gap S, an oil film axial length L, an oil film oil supply structure, an oil film end sealing structure and the like.
When the unbalanced response test is carried out on the squeeze film damper, oil supply with certain pressure is carried out on the squeeze film damper, the radial vibration of a rotor is measured by a displacement sensor, and the damping effect of the squeeze film damper is evaluated according to vibration data.
In some embodiments, the device for testing the damping effect of a squeeze film damper further comprises a weight member configured to be detachably provided to the rotor 2 to adjust the unbalance amount of the rotor 2, and the damping effect of the damper is measured by the unbalance response.
Optionally, the weight member comprises a screw.
When the unbalance response test is carried out on the squeeze film damper, a certain screw is additionally arranged on the rotating shaft 3, the test of lifting and rotating the rotating shaft at the critical rotating speed is carried out, the squeeze film damper is not supplied with oil, the radial vibration of the rotor is measured by using the displacement sensor, and the damping effect of the squeeze film damper is evaluated according to vibration data.
As shown in fig. 6, the diagram shows the damping effect measured by the testing device under a certain unbalance amount, wherein the horizontal axis represents the rotation speed and the vertical axis represents the amplitude. When the unbalanced response test is carried out on the squeeze film damper, oil supply with certain pressure is carried out on the squeeze film damper, the radial vibration of a rotor is measured by a displacement sensor, and the damping effect of the squeeze film damper is evaluated according to vibration data. When the unbalanced response test is carried out, the squeeze film damper is not supplied with oil, a certain screw is additionally arranged on the rotating shaft 3, the test of lifting and rotating the rotating shaft at the critical rotating speed is carried out, the radial vibration of the rotor is measured by using the displacement sensor, and the damping effect of the squeeze film damper is evaluated according to vibration data.
When the unbalanced response test is carried out on the squeeze film damper, the damping effect line graph obtained under the conditions of oil supply and no oil supply shows that when oil supply with certain pressure is carried out on the squeeze film damper, the amplitude of the rotor is small when the rotor passes through the critical rotating speed.
In some embodiments, the testing method of the testing device for the damping effect of the squeeze film damper comprises the following steps:
s1: assembling: assembling a squeeze film damper to the rotor, and mounting the rotor to the bracket and connecting with a driving motor;
s2: adjusting concentricity: the bolt 8 can be unscrewed, the gap between the outer ring 32 and the inner ring 31 of the squeeze film damper is adjusted by adjusting the first adjusting piece 41 in the vertical direction and the second adjusting piece 42 in the horizontal direction, so that the circumferential gap between the outer ring 32 and the inner ring 31 is uniform, a static eccentricity can be preset, and the bolt 8 is screwed after the adjustment is finished;
s3: unbalanced response test (squeeze film damper no oil feed): a certain unbalanced screw is additionally arranged on the rotating shaft 2, a test of lifting and rotating through a critical rotating speed is carried out (oil is not supplied to an extrusion oil film damper), and a displacement sensor is used for measuring the radial vibration of a rotor;
s4: unbalanced response test (squeeze film damper oil supply): supplying oil to the squeeze film damper at a certain pressure, performing an unbalance response test again with reference to step S3, and measuring the radial vibration of the rotor by using a displacement sensor;
s5: and (3) evaluating the damping effect: evaluating the damping effect of the squeeze film damper based on the test results of the steps S3 and S4;
s6: adjusting the structural parameters of the squeeze film damper: dismantling the nut 8 and the inner ring 31 of the squeeze film damper, replacing the inner ring 31 of the new squeeze film damper, and locking the inner ring 31 through the nut 8, wherein the adjustable damper structural parameters comprise an oil film radius gap S, an oil film axial length L, an oil film oil supply structure (an oil supply channel 321), an oil film end sealing structure (a first groove 311) and the like;
s7: adjusted test: and repeating S3, S4 and S5, and carrying out a damper damping test of new structural parameters.
In some embodiments, the testing device and the testing method for the damping effect of the squeeze film damper can adjust the structural parameters of the squeeze film damper, such as oil film radius clearance, oil film axial length, oil supply structure, end seal and the like, without disassembling the rotor and the main supporting piece, reduce the workload of disassembling and assembling the rotor, avoid secondary centering debugging, dynamic balance and the like caused by rotor reassembly, not only can actually measure the damping effect, but also can greatly improve the test efficiency; and the damping effect is closer to the actual application environment of damping through unbalance detection, and the test result is more reliable and credible.
Based on the above embodiments of the present invention, the technical features of one of the embodiments can be advantageously combined with one or more other embodiments without explicit negatives.
In the description of the present invention, it should be understood that the terms "first", "second", "third", etc. are used to define the components, and are only used for the convenience of distinguishing the components, and if not stated otherwise, the terms have no special meaning, and thus, should not be construed as limiting the scope of the present invention.
Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting the same; although the present invention has been described in detail with reference to preferred embodiments, it should be understood by those skilled in the art that: the invention can be modified or equivalent substituted for some technical features; without departing from the spirit of the present invention, it should be understood that the scope of the claims is intended to cover all such modifications and variations.
Claims (10)
1. The utility model provides a testing arrangement of squeeze film damper damping effect which characterized in that includes:
a support (1);
a rotor (2) rotatably provided to the bracket (1);
the squeeze film damper (3) comprises an inner ring (31) and an outer ring (32), the inner ring (31) is connected to the rotor (2), and the outer ring (32) is arranged on the periphery of the inner ring (31) and connected to the support (1); and
a plurality of adjustment assemblies (4) disposed at intervals along a circumferential direction of the outer ring (32) and configured to adjust concentricity of the outer ring (32) and the inner ring (31) and adjust a gap between the outer ring (32) and the inner ring (31).
2. The testing device of squeeze film damper damping effect according to claim 1, characterized in that each adjustment assembly (4) of the plurality of adjustment assemblies (4) comprises a first adjustment member (41) and a second adjustment member (42) perpendicular to each other, wherein the first adjustment member (41) is configured to adjust the position of the outer ring (32) in a vertical direction and the second adjustment member (42) is configured to adjust the position of the outer ring (32) in a horizontal direction.
3. The device for testing the damping effect of a squeeze film damper according to claim 2, characterized in that said first adjustment means (41) comprise first screws which are inserted through said support (1) and abut against said outer ring (32), and/or said second adjustment means (42) comprise second screws which are inserted through said support (1) and abut against said outer ring (32).
4. Testing device for the damping effect of a squeeze film damper according to claim 1, characterised in that the outer ring (32) is configured to be detachably arranged to the bracket (1).
5. Testing device for the damping effect of a squeeze film damper according to claim 1, characterized in that the inner ring (31) is configured to be detachably provided to the rotor (2).
6. The testing device for the damping effect of a squeeze film damper according to claim 1, further comprising a bearing (5) and an elastic support (6), wherein the bearing (5) is arranged at the end of the rotor (2), the elastic support (6) is arranged at the outer periphery of the bearing (5), and the inner ring (31) is arranged at the outer periphery of the elastic support (6).
7. The device for testing the damping effect of a squeeze film damper according to claim 6, further comprising a nut (7), said nut (7) being provided at the outer periphery of said elastic support (6) and being configured to abut against said inner ring (31).
8. The testing device for the damping effect of the squeeze film damper according to claim 1, wherein, along the axial direction of the rotor (2), the two ends of the inner ring (31) are respectively provided with a first groove (311), the outer ring (32) is provided with an oil supply channel (321), and the oil supply channel (321) is communicated with a gap between the inner ring (31) and the outer ring (32) between the two first grooves (311).
9. The testing device for the damping effect of the squeeze film damper according to claim 1, wherein, along the axial direction of the rotor (2), two ends of the inner ring (31) are respectively provided with a first groove (311), the inner ring (31) is further provided with a second groove (312), the second groove (312) is positioned between the two first grooves (311), the outer ring (32) is provided with an oil supply channel (321), and the oil supply channel (321) is communicated with the second groove (312).
10. The squeeze film damper damping effectiveness test device according to claim 1 further comprising a weight member configured to be removably attached to the rotor (2) to adjust the amount of unbalance of the rotor (2).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202120414541.4U CN214407995U (en) | 2021-02-25 | 2021-02-25 | Testing device for damping effect of squeeze film damper |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202120414541.4U CN214407995U (en) | 2021-02-25 | 2021-02-25 | Testing device for damping effect of squeeze film damper |
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| Publication Number | Publication Date |
|---|---|
| CN214407995U true CN214407995U (en) | 2021-10-15 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202120414541.4U Active CN214407995U (en) | 2021-02-25 | 2021-02-25 | Testing device for damping effect of squeeze film damper |
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| CN (1) | CN214407995U (en) |
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2021
- 2021-02-25 CN CN202120414541.4U patent/CN214407995U/en active Active
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