CN113740049A - Foil air bearing's air film pressure simulation equipment - Google Patents
Foil air bearing's air film pressure simulation equipment Download PDFInfo
- Publication number
- CN113740049A CN113740049A CN202111177947.6A CN202111177947A CN113740049A CN 113740049 A CN113740049 A CN 113740049A CN 202111177947 A CN202111177947 A CN 202111177947A CN 113740049 A CN113740049 A CN 113740049A
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- Prior art keywords
- foil
- air
- plate
- air bearing
- film pressure
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- 239000011888 foil Substances 0.000 title claims abstract description 146
- 238000004088 simulation Methods 0.000 title claims abstract description 26
- 238000007664 blowing Methods 0.000 claims abstract description 21
- 238000006073 displacement reaction Methods 0.000 claims description 34
- 239000007789 gas Substances 0.000 description 7
- 238000005507 spraying Methods 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000001125 extrusion Methods 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 230000001050 lubricating effect Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
Images
Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M13/00—Testing of machine parts
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L1/00—Measuring force or stress, in general
- G01L1/24—Measuring force or stress, in general by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M13/00—Testing of machine parts
- G01M13/04—Bearings
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Support Of The Bearing (AREA)
- Magnetic Bearings And Hydrostatic Bearings (AREA)
Abstract
The application discloses foil air bearing's air film pressure analog device, air film pressure analog device includes: a base plate for mounting a foil of a foil air bearing; a loading mechanism comprising a blowing tray and a nozzle connected to the blowing tray and directed toward the base plate for ejecting a stream of air onto the foil on the base plate to apply air pressure; a sensor module comprising a force sensor connected to an area of the base plate for placing the foil for detecting a pressure carried by the foil when the nozzle ejects an air flow towards the foil. According to the air film pressure simulation equipment of the foil air bearing, the foil is placed on the bottom plate, the air flow is sprayed to the foil on the bottom plate through the nozzle to apply air pressure, then the pressure borne by the foil under the action of the air pressure is detected through the force sensor below the foil, and the simulation of the working condition that the air pressure generated by the rotation of the rotor acts on the foil before the rotation of the rotor in the foil air bearing is stable is realized.
Description
Technical Field
The disclosure relates to the field of test equipment, in particular to an air film pressure simulation device of a foil air bearing.
Background
The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art.
The foil air bearing is used as a novel dynamic pressure air bearing, has the advantages of high rotating speed and rotation precision, small power consumption, no pollution, long service life, capability of working in severe working environment and the like of the traditional gas bearing, has the advantages of good adaptability, low requirement on manufacturing and assembling precision, good impact resistance, high stability, no need of a special lubricating and cooling system, low maintenance cost and the like, and is widely applied to high-speed rotating machinery such as air blowers, hydrogen fuel cell compressors, electronic turbochargers, airplane environment control systems { ACM), auxiliary power systems (APU), micro gas turbines, small aviation turbine engines and the like.
As shown in fig. 1, before the rotor is stabilized, the rotor 1 may generate different pressures in different directions and different magnitudes on the foil 2 of the foil air bearing, and may generate different degrees of extrusion deformation on the bump foil and the top foil of the foil air bearing.
Disclosure of Invention
In view of the above, it is necessary to provide an air film pressure simulation apparatus for a foil air bearing, which is used for simulating the working condition of a foil under the air pressure generated by the rotation of a rotor.
The present disclosure provides an air film pressure simulation apparatus of a foil air bearing, comprising:
a base plate for mounting a foil of a foil air bearing;
a loading mechanism comprising a blowing tray and a nozzle connected to the blowing tray and directed toward the base plate for ejecting a stream of air onto the foil on the base plate to apply air pressure;
a sensor module comprising a force sensor connected to an area of the base plate for placing the foil for detecting a pressure carried by the foil when the nozzle ejects an air flow towards the foil.
Preferably, the loading mechanism comprises a plurality of nozzles, and the nozzles are arranged on the blowing disc in a dot matrix manner.
Preferably, the loading mechanism further comprises a first displacement platform to which the blowing tray is connected, the first displacement platform being adapted to adjust the distance of the nozzle relative to the foil by moving the blowing tray in a vertical direction.
Preferably, the sensor module further comprises a deformation sensor for detecting a deformation amount of the foil at the nozzle by jetting the air flow to the foil.
Preferably, the deformation sensor comprises a grating micrometer facing the area of the base plate for placing the foil to detect the amount of deformation of the foil.
Preferably, the sensor module further comprises a fixing plate, the grating micrometer being connected to the fixing plate and facing the base plate.
Preferably, the sensor module further comprises a second displacement platform, the fixing plate is connected to the second displacement platform, and the second displacement platform is used for adjusting the distance between the grating micrometer and the foil by moving the fixing plate along the vertical direction.
Preferably, the foil sheets comprise a bump foil placed on the base plate and a top foil on the bump foil.
Preferably, the grating micrometer is located above the top foil to detect the amount of deformation of the top foil and the wave foil.
Preferably, the first displacement platform and the second displacement platform comprise a fixed frame, a moving plate, an adjusting rod and a locking assembly;
the movable plate is movably connected to the fixed frame along the vertical direction, and the adjusting rod is connected to the movable plate and abutted against the fixed frame and used for adjusting the position of the movable plate by abutting against the fixed frame when being extended or shortened;
the locking assembly comprises a connecting piece and a locking piece, the connecting piece is connected to the fixed frame and is provided with a long hole extending in the vertical direction, and the locking piece penetrates through the long hole to be connected to the moving plate so as to lock the moving plate.
Compared with the prior art, the foil is placed on the bottom plate by the air film pressure simulation equipment of the foil air bearing, the air flow is sprayed to the foil on the bottom plate through the nozzle to apply air pressure, then the pressure borne by the foil under the action of the air pressure is detected through the force sensor below the foil, and the simulation of the working condition that the air pressure generated by the rotation of the rotor acts on the foil before the rotation of the rotor in the foil air bearing is stable is realized.
Drawings
In order to illustrate the embodiments more clearly, the drawings that will be needed in the description of the embodiments will be briefly described below, it being apparent that the drawings in the following description are some examples of the disclosure, and that other drawings may be derived from those drawings by a person skilled in the art without inventive effort.
Figure 1 is a schematic representation of the pressure to which a foil is subjected under air film pressure.
Fig. 2 is a schematic structural view of an air film pressure simulation apparatus of a foil air bearing.
Fig. 3 is a schematic view of the structure of the base plate and the foil.
Fig. 4 is a schematic structural view of the loading mechanism.
Fig. 5 is a schematic structural diagram of the first displacement stage.
Fig. 6 is a schematic structural view of the grating micrometer and the second displacement stage.
Description of the main elements
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10 |
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20 |
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21 |
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22 |
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30 |
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31 |
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311 |
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312 |
Adjusting |
313 |
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3131 |
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3132 |
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314 |
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3141 |
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315 |
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32 |
Nozzle with a |
33 |
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40 |
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41 |
The following detailed description will further illustrate the disclosure in conjunction with the above-described figures.
Detailed Description
In order that the above objects, features and advantages of the present disclosure can be more clearly understood, a detailed description of the present disclosure will be given below with reference to the accompanying drawings and detailed description. In addition, the embodiments and features of the embodiments of the present application may be combined with each other without conflict. In the following description, numerous specific details are set forth to provide a thorough understanding of the present disclosure, and the described embodiments are merely a subset of the embodiments of the present disclosure, rather than a complete embodiment. All other embodiments, which can be derived by one of ordinary skill in the art from the embodiments disclosed herein without making any creative effort, shall fall within the protection scope of the present disclosure.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The terminology used in the description herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure.
In various embodiments, for convenience in description and not limitation of the disclosure, the term "coupled" as used in the specification and claims of the present disclosure is not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships are changed accordingly.
Fig. 2 is a schematic structural view of an air film pressure simulation apparatus of a foil air bearing. As shown in fig. 2, the air film pressure simulation apparatus of the foil air bearing is used to simulate the operation condition of the rotor before stable rotation, which is influenced by the air pressure generated by rotation on the foil of the foil air bearing. The gas film pressure simulation device comprises a base plate 10, a loading mechanism 30 and a sensor module 20, wherein the base plate 10 is used for bearing a foil to be tested, the loading mechanism 30 is used for applying a gas film with preset flow and air pressure to the foil, and the sensor module 20 is used for detecting various parameters of the foil under the action of the gas film formed by the air flow, so that the foil is evaluated under the working condition of the gas film pressure.
Fig. 2 is a schematic view of the structure of the base plate 10 and the foil. As shown in fig. 2, the base plate 10 has a substantially flat plate-like structure for mounting a foil of a foil air bearing. The bottom plate 10 has a substantially flat plate-like structure, and in the present embodiment, the bottom plate 10 is disposed in a horizontal direction, the foil pieces include a bump foil 40 and a top foil 41, the bump foil 40 is placed on the bottom plate 10, and the top foil 41 is located on the bump foil 40.
Fig. 4 is a schematic structural view of the loading mechanism 30. As shown in fig. 4, the loading mechanism 30 includes a first displacement stage 31, an air-blowing tray 32, and a nozzle 33. The first displacement platform 31 is used to mount the blow plate 32 and the nozzle 33, and can be accurately moved in the vertical direction to adjust the positions of the blow plate 32 and the nozzle 33. The blowing plate 32 is used to fix and mount the nozzle 33, and the nozzle 33 is used to spray air flow to simulate an air film generated by the rotation of the rotor.
Fig. 5 is a schematic structural view of the first displacement stage 31. As shown in fig. 5, the blowing tray 32 is connected to the first displacement platform 31, and the first displacement platform 31 is used for adjusting the distance of the nozzle 33 relative to the foil by moving the blowing tray 32 in the vertical direction. The first displacement platform 31 includes a fixed frame 311, a moving plate 312, an adjustment rod 313 and a locking assembly. In this embodiment, the fixing frame 311 may be installed on the bottom plate 10, and the moving plate 312 is movably connected to the fixing frame 311 in a vertical direction. For example, a slider and a slide rail structure are disposed between the moving plate 312 and the fixed frame 311, and the moving plate 312 and the fixed frame 311 are connected by the slider-slide rail structure, so that the moving plate 312 can move in a vertical direction relative to the fixed frame 311. The adjusting rod 313 is connected to the moving plate 312 and abuts against the fixed frame 311, and is used for adjusting the position of the moving plate 312 by abutting against the fixed frame 311 when being extended or shortened. Illustratively, the adjusting rod 313 includes a screw 3131 and a nut 3132, the nut 3132 is connected to the moving block, the screw 3131 is in threaded connection with the nut 3132, and the screw passes through the nut 3132 to abut on the fixed frame 311. In use, the screw 3131 is rotated to rotate the screw 3131 relative to the nut 3132, and the bottom of the screw 3131 abuts against the fixed frame 311, so that the moving plate 312 is driven to move, and the position of the moving plate 312 is precisely adjusted. The locking assembly includes a connecting piece 314 and a locking member 315, wherein the connecting piece 314 is connected to the fixing frame 311 and is provided with an elongated hole 3141 extending in a vertical direction. The locking member 315 may be a screw, and is coupled to the moving plate 312 through an elongated hole 3141 to lock the moving plate 312.
The blowing tray 32 is provided with a nozzle 33 for mounting and extends in the horizontal direction. The blow plate 32 is attached to the first displacement table 31 to adjust the position of the blow plate 32 in the vertical direction by the first displacement table 31. Specifically, the blow plate 32 is coupled to the moving plate 312 of the first displacement table 31 so that the position of the blow plate 32 can be adjusted by rotating the adjustment lever 313. The nozzle 33 extends in a vertical direction, is connected to the blowing tray 32 and faces the base plate 10, and is used for spraying an air flow to the foil on the base plate 10 to apply air pressure. In this embodiment, the plurality of nozzles 33 are disposed in the blowing plate 32 in a lattice shape, each nozzle 33 is independently connected to one air pipe, and the air pipes are connected to a control system, so that the flow rate and pressure passing through the air pipes can be independently controlled, and different pressures generated by the air pressure counter wave foil 40 and the top foil 41 before the actual rotor rotates in the foil air bearing to be stable are simulated.
The sensor module 20 includes a force sensor and a deformation sensor. The force sensor is connected to the area of the base plate 10 for placing the foil for detecting the pressure carried by the foil when the nozzle 33 jets an air flow towards the foil. When the foil carries the air flow emitted by the nozzle 33, the loading force applied to the foil can be detected by a force sensor provided below the foil on the base plate 10. The deformation sensor is used for detecting the deformation quantity of the foil at the nozzle 33 generated by jetting air flow to the foil. In some embodiments, the deformation sensor comprises a grating micrometer facing the area of the base plate 10 for placing the foil to detect the amount of deformation of the foil.
Fig. 6 is a schematic structural view of the grating micrometer and the second displacement stage 21. As shown in fig. 6, the sensor module 20 further includes a fixing plate 22, and the grating micrometer is connected to the fixing plate 22 and faces the base plate 10. The fixed plate 22 is connected to the moving plate 312 of the second displacement platform 21, and the second displacement platform 21 is used for adjusting the distance between the grating micrometer and the foil by moving the fixed plate 22 along the vertical direction. In use, the height of the second displacement platform 21 is adjusted, and the grating micrometer is driven by the fixing plate 22 to move until the grating micrometer is located above the top foil 41 to detect the deformation of the top foil 41 and the wave foil 40. Preferably, the structure of the second displacement platform 21 is the same as that of the first displacement platform 31, and the description thereof is omitted.
In operation, the bump foil 40 and the top foil 41 are fixed on the bottom plate 10 with the force sensor, the blowing tray 32 is fixed on the first displacement platform 31, and the distance between the nozzle 33 of the blowing tray 32 and the top foil 41 is precisely controlled by the first displacement platform 31.
Each nozzle 33 of the blowing disc 32 is connected with an independent air pipe, each air pipe independently controls the flow and the pressure of the air pipe through a control system, and the different pressures generated by the air pressure on the bump foil 40 and the top foil 41 before the actual rotor rotates in the foil air bearing to be stable are simulated by spraying air flow to the foil.
In the air jet process, the pressure born by the foil is acquired by a force sensor, and the deformation quantity of the top foil 41 is acquired by a grating micrometer.
Finally, the collected data are transmitted to a computer, and the collected data are analyzed after fitting with different air pressures sprayed by the nozzles 33.
According to the air film pressure simulation equipment of the foil air bearing, the foil is placed on the bottom plate 10, the air flow is sprayed to the foil on the bottom plate 10 through the nozzle 33 to apply air pressure, then the pressure borne by the foil under the action of the air pressure is detected through the force sensor below the foil, and the simulation of the working condition that the air pressure generated by the rotation of the rotor acts on the foil before the rotation of the rotor in the foil air bearing is stable is realized. The gas film pressure simulation equipment of the foil air bearing is simple in structure and convenient to build and debug, can easily replace the bump foil 40 and the top foil 41 to be tested, and can simulate the influence of air pressure on the bump foil 40 and the top foil 41 before the rotor rotates in the foil air bearing to be stable under different working conditions.
In several embodiments provided in the present disclosure, it will be apparent to those skilled in the art that the present disclosure is not limited to the details of the above-described exemplary embodiments, and can be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the disclosure being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Furthermore, it is obvious that the word "comprising" does not exclude other elements or steps, and the singular does not exclude the plural. The terms first, second, etc. are used to denote names, but not any particular order.
Although the present disclosure has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit and scope of the present disclosure.
Claims (10)
1. An air film pressure simulation apparatus for a foil air bearing, comprising:
a base plate for mounting a foil of a foil air bearing;
a loading mechanism comprising a blowing tray and a nozzle connected to the blowing tray and directed toward the base plate for ejecting a stream of air onto the foil on the base plate to apply air pressure;
a sensor module comprising a force sensor connected to an area of the base plate for placing the foil for detecting a pressure carried by the foil when the nozzle ejects an air flow towards the foil.
2. The foil air bearing air film pressure simulation apparatus of claim 1, wherein the loading mechanism comprises a plurality of nozzles disposed in a lattice pattern on the blowing plate.
3. The foil air bearing film pressure simulation apparatus of claim 2, wherein the loading mechanism further comprises a first displacement stage to which the blow plate is connected, the first displacement stage being configured to adjust the distance of the nozzle relative to the foil by moving the blow plate in a vertical direction.
4. The foil air bearing air film pressure simulation apparatus of claim 3, wherein the sensor module further comprises a deformation sensor for detecting a deformation amount of the foil at the nozzle by jetting an air flow to the foil.
5. The foil air bearing air film pressure simulation apparatus of claim 4, wherein the deformation sensor comprises a grating micrometer facing an area of the base plate for placing the foil to detect the amount of deformation of the foil.
6. The foil air bearing air film pressure simulation apparatus of claim 5, wherein the sensor module further comprises a fixture plate, the grating micrometer being coupled to the fixture plate and facing the base plate.
7. The foil air bearing air film pressure simulation apparatus of claim 6, wherein the sensor module further comprises a second displacement platform, the fixed plate being connected to the second displacement platform, the second displacement platform being configured to adjust the distance of the grating micrometer from the foil by moving the fixed plate in a vertical direction.
8. The foil air bearing film pressure simulation apparatus of claim 7, wherein the foil includes a bump foil and a top foil, the bump foil being placed on the base plate, the top foil being on the bump foil.
9. The foil air bearing air film pressure simulation apparatus of claim 8, wherein the grating micrometer is positioned above the top foil to detect the amount of deformation of the top foil and the bump foil.
10. The foil air bearing film pressure simulation apparatus of claim 9, wherein the first and second displacement stages comprise a fixed mount, a moving plate, an adjustment lever, and a locking assembly;
the movable plate is movably connected to the fixed frame along the vertical direction, and the adjusting rod is connected to the movable plate and abutted against the fixed frame and used for adjusting the position of the movable plate by abutting against the fixed frame when being extended or shortened;
the locking assembly comprises a connecting piece and a locking piece, the connecting piece is connected to the fixed frame and is provided with a long hole extending in the vertical direction, and the locking piece penetrates through the long hole to be connected to the moving plate so as to lock the moving plate.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202111177947.6A CN113740049A (en) | 2021-10-09 | 2021-10-09 | Foil air bearing's air film pressure simulation equipment |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202111177947.6A CN113740049A (en) | 2021-10-09 | 2021-10-09 | Foil air bearing's air film pressure simulation equipment |
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Publication Number | Publication Date |
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CN113740049A true CN113740049A (en) | 2021-12-03 |
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CN202111177947.6A Pending CN113740049A (en) | 2021-10-09 | 2021-10-09 | Foil air bearing's air film pressure simulation equipment |
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CN (1) | CN113740049A (en) |
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2021
- 2021-10-09 CN CN202111177947.6A patent/CN113740049A/en active Pending
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Address after: 523808 Room 301, building 2, No. 8, North 1st Street, Dalingshan lake, Dalingshan Town, Dongguan City, Guangdong Province Applicant after: Dongguan Qingrui Technology Co.,Ltd. Address before: 523852 room 229, building 6, No. 96, Chang'an Zhen'an East Road, Chang'an Town, Dongguan City, Guangdong Province Applicant before: Dongguan Qingrui Technology Co.,Ltd. |