CN110822013B - A squeeze film damper with a semi-arcuate annular boost boss - Google Patents
A squeeze film damper with a semi-arcuate annular boost boss Download PDFInfo
- Publication number
- CN110822013B CN110822013B CN201911238932.9A CN201911238932A CN110822013B CN 110822013 B CN110822013 B CN 110822013B CN 201911238932 A CN201911238932 A CN 201911238932A CN 110822013 B CN110822013 B CN 110822013B
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- China
- Prior art keywords
- damper
- semi
- oil film
- annular boss
- arched
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- 239000003921 oil Substances 0.000 claims description 105
- 238000001125 extrusion Methods 0.000 claims description 27
- 241000555745 Sciuridae Species 0.000 claims description 11
- 239000010687 lubricating oil Substances 0.000 claims description 7
- 238000013016 damping Methods 0.000 abstract description 17
- 238000007789 sealing Methods 0.000 abstract description 7
- 230000000694 effects Effects 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000000452 restraining effect Effects 0.000 description 1
- 230000007847 structural defect Effects 0.000 description 1
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F15/00—Suppression of vibrations in systems; Means or arrangements for avoiding or reducing out-of-balance forces, e.g. due to motion
- F16F15/02—Suppression of vibrations of non-rotating, e.g. reciprocating systems; Suppression of vibrations of rotating systems by use of members not moving with the rotating systems
- F16F15/023—Suppression of vibrations of non-rotating, e.g. reciprocating systems; Suppression of vibrations of rotating systems by use of members not moving with the rotating systems using fluid means
- F16F15/0237—Suppression of vibrations of non-rotating, e.g. reciprocating systems; Suppression of vibrations of rotating systems by use of members not moving with the rotating systems using fluid means involving squeeze-film damping
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C27/00—Elastic or yielding bearings or bearing supports, for exclusively rotary movement
- F16C27/04—Ball or roller bearings, e.g. with resilient rolling bodies
- F16C27/045—Ball or roller bearings, e.g. with resilient rolling bodies with a fluid film, e.g. squeeze film damping
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F2228/00—Functional characteristics, e.g. variability, frequency-dependence
- F16F2228/06—Stiffness
- F16F2228/066—Variable stiffness
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Aviation & Aerospace Engineering (AREA)
- Support Of The Bearing (AREA)
Abstract
本发明公开了一种带半圆弧环形增压凸台的挤压油膜阻尼器，包括半圆弧环形凸台，阻尼器外环和/或阻尼器内环轴向端部分别增加半圆弧环形凸台。为了保证阻尼器的工作范围不超过0.4倍的油膜间隙，半圆弧环形凸台径向高度为半径r，半圆弧环形凸台的径向高度r不超过0.5倍的油膜间隙，不小于0.4倍的油膜间隙，半圆弧环形凸台的圆心位于阻尼器内环或外环轴向平面外的点O1，以轴向截面端点为圆心O，半圆弧环形凸台的半径R为O1到半圆弧环形凸台径向最高点的距离，其中该结构的挤压油膜阻尼器能够有效的起到油膜密封作用，保证油膜的完整性，增大油膜压力，抑制端部空气吸入，提高油膜阻尼，更高效地吸收转子振动产生地能量，提高系统的稳定性。The present invention discloses a squeeze film damper with a semicircular annular boosting boss, comprising a semicircular annular boss, and the semicircular annular boss is added to the axial ends of the damper outer ring and/or the damper inner ring. In order to ensure that the working range of the damper does not exceed 0.4 times of the oil film gap, the radial height of the semicircular annular boss is the radius r, the radial height r of the semicircular annular boss does not exceed 0.5 times of the oil film gap, and is not less than 0.4 times of the oil film gap, the center of the semicircular annular boss is located at point O 1 outside the axial plane of the damper inner ring or outer ring, with the end point of the axial section as the center O, the radius R of the semicircular annular boss is the distance from O 1 to the radial highest point of the semicircular annular boss, wherein The squeeze film damper of this structure can effectively play the role of oil film sealing, ensure the integrity of the oil film, increase the oil film pressure, inhibit the end air intake, improve the oil film damping, more efficiently absorb the energy generated by the rotor vibration, and improve the stability of the system.
Description
Technical Field
The invention belongs to the technical field of aeroengine vibration reduction, and particularly relates to an extrusion oil film damper with a semi-arched annular pressurizing boss.
Background
Squeeze film dampers are commonly used in rotary machines as a vibration damping device to reduce vibration generated by the rotor by providing viscous damping. With the development of rotating machinery towards high rotation speed and high efficiency, higher requirements are also put on the vibration damping performance of the extrusion oil film damper.
For a damper, the oil film damping and stiffness are approximately considered to be linear changes with eccentricity (dynamic eccentricity/oil film gap) of no more than 0.4, and nonlinear changes occur as the eccentricity increases.
The squeeze film damper is classified into an open squeeze film damper without oil seal and a closed squeeze film damper with oil seal ring according to the presence or absence of an end oil seal device.
In the open type extrusion oil film damper, lubricating oil fills a gap formed by an elastic support outer ring and a base inner ring, an oil film is extruded through external transmission force generated by rotor vibration, and oil film counter force is generated by the oil film to provide damping and absorb vibration energy. The open damper has the following disadvantages:
1. Because the two ends are not provided with oil sealing devices, the lubricating oil directly flows out along the two axial ends, so that the oil film extrusion at the end part is insufficient, the effective extrusion area of the oil film is reduced, and enough oil film damping cannot be generated;
2. The axial end is in direct contact with the outside air, and when the oil film pressure is lower than the ambient pressure, an air suction phenomenon can occur, and the phenomenon commonly occurs in an open damper, which can also cause the reduction of the oil film damping of the damper, and a good vibration reduction effect cannot be generated.
The closed extrusion oil film damper is provided with an oil seal ring structure at the end, wherein the oil seal ring is generally an O-shaped oil seal ring or a piston ring. The oil seal ring can play a certain role in sealing oil, and the purpose is to keep the oil film intact. However, the closed damper has the disadvantages that:
1. The oil seal ring has the problems of friction, assembly, oil seal ring manufacture, replacement and the like, which increases the uncertainty of the vibration reduction performance of the damper and influences the vibration reduction reliability of the damper.
2. The oil seal ring can increase the damping effect of the damper, but has the problems that the oil seal ring rubs with the inner ring and the outer ring of the damper for a long time, so that lubricating oil is extruded out from the gap end part of the damper, the temperature of an oil film is too high, and the like. This will reduce the oil film damping and will not produce a good vibration damping effect.
Therefore, the damper with the semi-arched annular boss is designed to well overcome the structural defects of open type dampers and closed type dampers, the oil film damping and the oil film pressure can be improved by adding the semi-arched annular boss, the end oil film extrusion effect is enhanced, air suction is restrained, meanwhile, the working range of the damper is controlled to be not more than 0.4 times of oil film gap by adding the semi-arched annular boss, and the working range is used for guaranteeing that the oil film damping provided by the damper is in linear change and restraining the nonlinear change of the oil film rigidity.
Disclosure of Invention
Aiming at the defects existing in the existing extrusion oil film damper, the invention provides the extrusion oil film damper with the semi-arched annular pressurizing boss, which can effectively play a role in oil film sealing, ensure the integrity of an oil film, increase the pressure of the oil film, inhibit the suction of air at the end part, improve the oil film damping, more efficiently absorb the energy generated by the vibration of a rotor, improve the stability of a system, and has the advantages of simple structure, strong reliability and certain self-adaptability. The technical scheme adopted by the invention is as follows:
The extrusion oil film damper with the semi-arched annular pressurizing boss comprises a damper base, a squirrel cage elastic support, an oil supply groove and an oil supply hole, wherein an inner ring of the damper base is used as an outer ring of the damper, the squirrel cage elastic support comprises a support section, a squirrel cage bar and an extension section, the support section is fixedly connected with the damper base, an outer ring of the extension section is used as an inner ring of the damper, the outer ring of the damper and the inner ring of the damper form clearance fit, the clearance is filled with lubricating oil to form an oil film, the outer ring of the damper is provided with an annular groove which is used as the oil supply groove, a through hole which is communicated with the oil supply groove is used as the oil supply hole, a bearing and the squirrel cage elastic support are assembled concentrically, and a rotor is sleeved in the bearing.
The damper further comprises a semi-arched annular boss, and the axial end parts of the damper outer ring and/or the damper inner ring are respectively added with the semi-arched annular boss.
In order to ensure that the working range of the damper is not more than 0.4 times of oil film gap, the radial height of the semi-arched annular boss is radius R, the radial height R of the semi-arched annular boss is not more than 0.5 times of oil film gap and not less than 0.4 times of oil film gap, the circle center of the semi-arched annular boss is positioned at a point O 1 outside the axial plane of the inner ring or the outer ring of the damper, the end point of the axial section is taken as the circle center O, and the radius R of the semi-arched annular boss is the distance from O 1 to the radial highest point of the semi-arched annular boss, wherein R=r.
The radial extrusion degree of the oil film can be increased by the boss through the geometry of the semi-arched annular boss, and the top angle of the semi-arched annular boss is smaller, so that a larger distance is reserved between the outer wall of the semi-arched annular boss and the inner annular wall of the damper, and the outer wall of the damper cannot generate obvious friction phenomenon with the corresponding inner wall and outer wall of the damper in the working state of the damper, thereby having certain self-adaptability in the working state of the damper.
The extrusion oil film damper with the semi-arched annular pressurizing boss has the advantages that the semi-arched annular boss is formed through reasonable size arrangement, and the extrusion oil film damper has the following advantages:
(1) The invention has simple structure, and the semi-arched annular bosses are respectively added at the two axial ends of the inner ring and/or the outer ring of the damper to form the integral oil sealing structure at the two axial ends of the oil film, so that the process manufacturing difficulty and the processing cost are hardly increased.
(2) Compared with the traditional open damper, the end oil film pressure is increased, the outflow of the lubricating oil along the axial direction is blocked, the suction of the air at the end is inhibited, and the integrity of the oil film is ensured.
(3) Compared with the traditional closed damper, by adding the semi-arched fixing sealing structure at the end part, the oil temperature is prevented from being too high, the oil sealing ring is prevented from being replaced, and the use cost is reduced. Meanwhile, the extrusion stress condition of the oil film at the end part is changed, so that the oil film is subjected to annular extrusion, the pressure distribution at the end part of the oil film is changed, the pressure is improved, and the oil film damping is increased.
(4) By changing the extrusion direction of the oil film at the end part, the oil film is extruded more fully, the tangential force of the oil film is improved, the damping distribution range of the oil film is enlarged, and the vibration reduction performance is improved.
(5) In order to assemble the semi-arched annular boss and the damper and prevent the semi-arched annular boss from rubbing the damper, the radial height r of the semi-arched annular boss is set to be not more than 0.5 times of oil film gap and not less than 0.4 times of oil film gap, the working range of the damper is controlled to be not more than 0.4 times of oil film gap, the linear change of the oil film damping of the damper is ensured, the nonlinear change of the oil film rigidity of the damper is restrained, and the system stability is improved.
Drawings
FIG. 1 is a schematic view of an squeeze film damper of the present invention;
FIG. 2 is a schematic diagram of a semi-arcuate annular boss structure of the present invention, wherein (a) annular bosses are added to an inner ring and an outer ring of a damper, (b) annular bosses are added to the inner ring of the damper, and (c) annular bosses are added to the outer ring of the damper;
FIG. 3 is an enlarged partial view of a semi-arcuate annular boss of the present invention;
FIG. 4 is a schematic illustration of oil film extrusion in accordance with the present invention;
Fig. 5 is a schematic diagram of the semi-arcuate annular boss geometry of the present invention.
The symbol illustration comprises a 1-damper base, a 2-damper outer ring, a 3-squirrel cage elastic support, a 32-support section, 34-squirrel cage bars, a 36-extension section, a 4-damper inner ring, a 5-oil film, a 6-oil supply groove, a 7-oil supply hole, an 8-rotor and a 9-semi-arched annular boss.
Detailed Description
In order that the invention may be more clearly understood, the invention will be described in further detail with reference to the accompanying drawings.
An extrusion oil film damper with a semi-arcuate annular plenum boss provided in accordance with an embodiment of the present invention is described below with reference to fig. 1-5.
As shown in fig. 1, the extrusion oil film damper with the semi-arched annular pressurizing boss comprises a damper base 1, wherein an inner ring of the damper base 1 is used as a damper outer ring 2, a squirrel cage elastic support 3 comprises a support section 32 and a squirrel cage bar 34, an extension section 36, the support section 32 is fixedly connected with the damper base 1, the outer ring of the extension section 36 is used as a damper inner ring 4, the damper outer ring 2 and the damper inner ring 4 form clearance fit, the clearance is filled with lubricating oil to form an oil film 5, the damper outer ring 2 is provided with an annular groove serving as an oil supply groove 6, a through hole is formed to be communicated with the oil supply groove 6 to serve as an oil supply hole 7, a bearing is assembled concentrically with the squirrel cage elastic support 3, and a rotor 8 is sleeved in the bearing.
As shown in fig. 2 to 5, the damper outer ring 2 and/or the damper inner ring 4 are each provided with a semi-arcuate annular boss 9 at an axial end thereof.
In order to ensure that the working range of the damper is not more than 0.4 times of oil film gap, the radial height of the semi-arched annular boss 9 is radius R, the radial height R of the semi-arched annular boss 9 is not more than 0.5 times of oil film gap, not less than 0.4 times of oil film gap, the circle center of the semi-arched annular boss 9 is positioned at a point O 1 outside the axial plane of the inner ring or the outer ring of the damper, the end point of the axial section is taken as the circle center O, and the radius R of the semi-arched annular boss 9 is the distance from O 1 to the radial highest point of the semi-arched annular boss 9, wherein R=r.
The working principle of the invention is that the extrusion oil film damper is based on the extrusion oil film principle. In particular, when the rotor approaches the critical rotation speed, larger external force transmission and larger amplitude are generated, the external force transmission and the larger amplitude are transmitted to the extrusion oil film damper through the bearing, radial oil film force distribution is generated through an oil film between an outer ring of the extrusion damper and an inner ring of the damper, meanwhile, annular oil film force distribution is generated through extrusion of the oil film by a semi-arched annular boss, and energy generated by rotor vibration is absorbed through the oil film force, so that the rotor passes through the critical rotation speed as soon as possible, and the stability of a rotor system is improved.
Claims (1)
1. The extrusion oil film damper with the semi-arched annular pressurizing boss is characterized by comprising a damper base (1), a squirrel cage elastic support (3), an oil supply groove (6) and an oil supply hole (7), wherein an inner ring of the damper base (1) is used as a damper outer ring (2), the squirrel cage elastic support (3) comprises a support section (32), a squirrel cage bar (34) and an extension section (36), the support section (32) is fixedly connected with the damper base (1), an outer ring of the extension section (36) is used as a damper inner ring (4), the damper outer ring (2) and the damper inner ring (4) form clearance fit, the clearance is filled with lubricating oil to form an oil film (5), the damper outer ring (2) is provided with an annular groove which is used as an oil supply groove (6), a through hole is formed to be communicated with the oil supply groove (6), the bearing is concentrically assembled with the squirrel cage elastic support (3), and a rotor (8) is sleeved in the bearing, and the extrusion oil film damper is further characterized by comprising a semi-arched annular boss (9), and the damper outer ring (2) and/or the damper inner ring (4) are axially provided with the semi-arched annular boss (9);
The radial height r of the semi-arched annular boss (9) is not more than 0.5 times of oil film gap and not less than 0.4 times of oil film gap;
The semi-arched annular boss (9) is positioned at a point O 1 outside the axial plane of the damper inner ring (4) or the damper outer ring, the end point of the axial section is taken as the circle center O, the radius R of the semi-arched annular boss (9) is the distance R from O 1 to the radial highest point of the semi-arched annular boss (9), wherein R = R, r is the radial height of the semi-arcuate annular boss, O 1 o=r;
The circle center of the fan ring of the semi-arched annular boss (9) is O 1, and the sector of the semi-arched shape taking O 1 as the circle center is obtained by removing an isosceles right triangle taking R as a bevel edge and R as a right angle edge.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911238932.9A CN110822013B (en) | 2019-12-06 | 2019-12-06 | A squeeze film damper with a semi-arcuate annular boost boss |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911238932.9A CN110822013B (en) | 2019-12-06 | 2019-12-06 | A squeeze film damper with a semi-arcuate annular boost boss |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110822013A CN110822013A (en) | 2020-02-21 |
| CN110822013B true CN110822013B (en) | 2025-01-07 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911238932.9A Active CN110822013B (en) | 2019-12-06 | 2019-12-06 | A squeeze film damper with a semi-arcuate annular boost boss |
Country Status (1)
| Country | Link |
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| CN (1) | CN110822013B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114877003B (en) * | 2022-04-02 | 2023-06-20 | 哈尔滨工业大学 | A Novel Squeeze Film Damper with Adaptive Check Valve in the Oil Supply Hole |
| CN118583508B (en) * | 2024-07-30 | 2024-09-27 | 中国空气动力研究与发展中心空天技术研究所 | Design method of multifunctional supporting mechanism and supporting mechanism |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4867655A (en) * | 1988-03-14 | 1989-09-19 | United Technologies Corporation | Variable stiffness oil film damper |
| CN109139796A (en) * | 2018-10-22 | 2019-01-04 | 沈阳航空航天大学 | A kind of fixed end seal formula squeeze film damper |
| CN211449502U (en) * | 2019-12-06 | 2020-09-08 | 沈阳航空航天大学 | Squeeze film damper with semi-circular-arc annular pressurizing boss |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5067825A (en) * | 1990-06-18 | 1991-11-26 | Vance John M | Aircraft engine rotor squeeze film damper |
| US7648278B2 (en) * | 2007-01-05 | 2010-01-19 | Honeywell International Inc. | High speed aerospace generator resilient mount, combined centering spring and squeeze film damper |
| GB2459268B (en) * | 2008-04-16 | 2010-02-24 | Rolls Royce Plc | A squeeze-film damper arrangement |
| JP5167514B2 (en) * | 2008-05-29 | 2013-03-21 | Ｎｔｎ株式会社 | Rolling bearing assembly |
| FR2965858B1 (en) * | 2010-10-07 | 2012-11-02 | Turbomeca | LIQUID FILM COMPRESSION DAMPER |
| CN104358820B (en) * | 2014-11-28 | 2016-03-23 | 哈尔滨广瀚燃气轮机有限公司 | With the returning type elastic support of film damper |
| JP6839565B2 (en) * | 2017-02-24 | 2021-03-10 | 本田技研工業株式会社 | Squeeze film damper bearing device |
| CN108119603B (en) * | 2017-12-07 | 2019-10-11 | 南京航空航天大学 | A Vibration Damping Ring Device Based on Piezoelectric Stack |
| CN108131421A (en) * | 2017-12-27 | 2018-06-08 | 哈尔滨广瀚燃气轮机有限公司 | A kind of elastic ring squeeze film damper with special-shaped aperture |
-
2019
- 2019-12-06 CN CN201911238932.9A patent/CN110822013B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4867655A (en) * | 1988-03-14 | 1989-09-19 | United Technologies Corporation | Variable stiffness oil film damper |
| CN109139796A (en) * | 2018-10-22 | 2019-01-04 | 沈阳航空航天大学 | A kind of fixed end seal formula squeeze film damper |
| CN211449502U (en) * | 2019-12-06 | 2020-09-08 | 沈阳航空航天大学 | Squeeze film damper with semi-circular-arc annular pressurizing boss |
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| Publication number | Publication date |
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| CN110822013A (en) | 2020-02-21 |
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