CN118088429B - Vibration acquisition system of aviation high-pressure axial plunger pump and use method - Google Patents
Vibration acquisition system of aviation high-pressure axial plunger pump and use method Download PDFInfo
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- CN118088429B CN118088429B CN202410509238.0A CN202410509238A CN118088429B CN 118088429 B CN118088429 B CN 118088429B CN 202410509238 A CN202410509238 A CN 202410509238A CN 118088429 B CN118088429 B CN 118088429B
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- 230000001133 acceleration Effects 0.000 claims abstract description 106
- 238000009434 installation Methods 0.000 claims description 7
- 238000004364 calculation method Methods 0.000 claims description 6
- 238000005070 sampling Methods 0.000 claims description 5
- 238000001914 filtration Methods 0.000 claims description 3
- 238000005457 optimization Methods 0.000 claims description 3
- 238000003745 diagnosis Methods 0.000 abstract description 9
- 230000007246 mechanism Effects 0.000 abstract description 5
- 230000015572 biosynthetic process Effects 0.000 abstract description 3
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- 238000004458 analytical method Methods 0.000 description 1
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- 239000003638 chemical reducing agent Substances 0.000 description 1
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G01H11/00—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by detecting changes in electric or magnetic properties
- G01H11/06—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by detecting changes in electric or magnetic properties by electric means
- G01H11/08—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by detecting changes in electric or magnetic properties by electric means using piezoelectric devices
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B51/00—Testing machines, pumps, or pumping installations
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T90/00—Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Testing Of Devices, Machine Parts, Or Other Structures Thereof (AREA)
- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
Abstract
The invention discloses a vibration acquisition system of an aviation high-pressure axial plunger pump and a use method thereof, belonging to the technical field of aircraft hydraulic systems, wherein the vibration acquisition system comprises a test bed, a plurality of acceleration sensors, a charge amplifier and a signal analyzer; an axial plunger pump flange is fixed on the test stand; the charge amplifier is electrically connected with the signal analyzer; the contribution degree of each component of the aviation high-pressure axial plunger pump to vibration is judged by establishing a ground test bench, arranging acceleration sensors in different directions, collecting and decomposing vibration signals in different frequency bands, and the instantaneous acceleration value, the effective value and the full-period vibration characteristic in different frequency bands can be accurately captured, so that the characteristics in the signals are extracted and analyzed, a fault formation mechanism is finally obtained, the device is suitable for working environment sounds with loud noise in an aircraft system, and the problem that a hydraulic plunger pump fault diagnosis device in the prior art cannot be suitable for the aircraft system is solved.
Description
Technical Field
The invention belongs to the technical field of aircraft hydraulic systems, and particularly relates to an aviation high-pressure axial plunger pump vibration acquisition system and a use method thereof.
Background
The hydraulic system is one of three core systems of the aircraft, is widely applied to front wheel turning, landing gear retraction, aileron, slat, spoiler operation, main brake, speed reducer retraction, elevator, rudder and other mechanisms of the aircraft, and directly relates to flight safety. The aviation high-pressure axial plunger pump is a core component of an aircraft hydraulic system and is also one of high-frequency components in the hydraulic system. With the rapid development of high-pressure and high-speed aviation high-pressure axial plunger pumps, the structure of a hydraulic system is more and more complex, and the fault forms are more and more.
In the prior art, a diagnosis device specially aiming at the fault of the hydraulic plunger pump is provided, for example, patent publication number is CN114109800A, and the name is a hydraulic plunger pump fault diagnosis device and method based on a sound recognition technology. However, the hydraulic plunger pump fault diagnosis device and method are not suitable for an aircraft system, because in the aircraft system, engine noise is far greater than plunger pump sound, and the hydraulic plunger pump fault diagnosis device and method cannot accurately collect working environment sound of the hydraulic plunger pump, so that the hydraulic plunger pump fault cannot be accurately analyzed, and a theoretical basis cannot be provided for optimizing each component in the axial plunger pump.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides an aviation high-pressure axial plunger pump vibration acquisition system and an analysis method, which solve the problem that a hydraulic plunger pump fault diagnosis device in the prior art cannot provide a theoretical basis for optimizing each part in an axial plunger pump because the hydraulic plunger pump fault diagnosis device cannot be applied to an aircraft system.
In order to achieve the aim of the invention, the invention adopts the following technical scheme:
the vibration acquisition system comprises a test bed, a plurality of acceleration sensors, a charge amplifier and a signal analyzer; an axial plunger pump flange for installing the axial plunger pump is fixed on the test bed; the plurality of acceleration sensors comprise an X-axis acceleration sensor, a Y-axis acceleration sensor and a Z-axis acceleration sensor which are electrically connected with the charge amplifier; the charge amplifier is electrically connected with the signal analyzer.
Further, as a specific choice of the X-axis acceleration sensor, the Y-axis acceleration sensor, and the Z-axis acceleration sensor, the X-axis acceleration sensor, the Y-axis acceleration sensor, and the Z-axis acceleration sensor are charge-type piezoelectric acceleration sensors, the measuring range is 1000g, the response frequency is 25KHz, and the accuracy is ±0.5%.
Further, the sampling frequency of the signal analyzer is 2-5 times of the response frequency of the acceleration sensor. If the sampling rate is low during the fault of the plunger pump, the accurate fault frequency can not be adopted, and if the sampling rate is 2-5 times, the fault frequency can be accurately contained.
Further, as a specific installation mode of the X-axis acceleration sensor, the Y-axis acceleration sensor and the Z-axis acceleration sensor, the installation directions of the X-axis acceleration sensor and the Y-axis acceleration sensor are perpendicular to the axial plunger pump rotation shaft; the installation direction of the Z-axis acceleration sensor is parallel to the axial plunger pump rotation shaft.
Further, the invention also provides a use method of the vibration acquisition system of the aviation high-pressure axial plunger pump, which comprises the following steps:
s1, mounting an axial plunger pump on an axial plunger pump flange;
S2, starting the axial plunger pump, and collecting X, Y, Z axial acceleration signals of the full frequency band of the axial plunger pump under different working conditions;
s3, obtaining effective values and maximum values of acceleration signals of multiple sections of different frequency sections;
and S4, comparing the effective values and the maximum values of the acceleration signals of the multiple sections of different frequency sections to obtain components of the axial plunger pump affecting the acceleration amplitude, and providing an optimization rule.
Further, in step S2, at least three cycles are collected for each condition.
Further, in step S3, effective values of acceleration signals in frequency bands of 0 to 1000hz, 1000hz to 3000hz, 3000hz to 6000hz and 6000hz to 10000hz are obtained through band-pass filtering.
0-1000 Hz is the fundamental frequency range of the plunger pump, and mainly identifies the change of the fundamental frequency of the plunger pump; 1000 Hz-3000 Hz is the frequency multiplication of the plunger pump 1 or 2, 3000 Hz-6000 Hz is the frequency multiplication of the plunger pump 3-4, and the high-order frequency excited by the failure of the rotating part is mainly identified; if the frequency is unrecognizable from 1000Hz to 3000Hz, the frequency from 3000Hz to 6000Hz contains the corresponding characteristic higher order frequency. The 6000 Hz-10000 Hz is the high-frequency noise band.
Further, in step S3, the effective value calculation formula of the acceleration signal is:
wherein X (T) is the instantaneous acceleration amplitude at a certain moment, T is a period time, X RMS is the effective value of acceleration in the period of T, and T is a certain moment;
the maximum value calculation formula of the acceleration signal is:
where max is the maximum sign.
The beneficial effects of the invention are as follows: according to the vibration acquisition system and the use method of the aviation high-pressure axial plunger pump, provided by the invention, the contribution degree of each component of the aviation high-pressure axial plunger pump to vibration is judged by establishing a ground test bed, arranging acceleration sensors in different directions, acquiring and decomposing vibration signals in different frequency bands, and the instantaneous acceleration values, the effective values and the full-period vibration characteristics in different frequency bands can be accurately captured, so that the characteristics in the signals are extracted and analyzed, a failure formation mechanism is finally obtained, the system is suitable for working environment sounds with loud noise in an aircraft system, and the problem that a hydraulic plunger pump failure diagnosis device in the prior art cannot be suitable for the aircraft system is solved.
Drawings
Fig. 1 is a schematic structural diagram of an aviation high-pressure axial plunger pump vibration acquisition system.
Fig. 2 is a schematic diagram of a Z-direction acceleration value acquired by the Z-axis acceleration sensor.
Fig. 3 is a schematic diagram of the effective values of the Z-direction and X-direction acceleration signals.
FIG. 4 is a schematic diagram of the effective value of the Z-direction acceleration signal at multiple different frequency bins.
Fig. 5 is a schematic diagram of the Z acceleration signal effective value of an axial plunger pump with a buffer bottle.
Fig. 6 is a schematic diagram of the Z-direction acceleration signal effective value of an axial plunger pump without a buffer bottle.
1, A ground test bench; 2. a Z-axis acceleration sensor; 3. a Y-axis acceleration sensor; 4. an X-axis acceleration sensor; 5. an axial plunger pump flange; 6. an axial plunger pump; 7. a charge amplifier; 8. a signal analyzer.
Detailed Description
The following description of the embodiments of the present invention is provided to facilitate understanding of the present invention by those skilled in the art, but it should be understood that the present invention is not limited to the scope of the embodiments, and all the inventions which make use of the inventive concept are protected by the spirit and scope of the present invention as defined and defined in the appended claims to those skilled in the art.
As shown in fig. 1, the invention provides an aviation high-pressure axial plunger pump vibration acquisition system, which is characterized by comprising a test bed, a plurality of acceleration sensors, a charge amplifier 7 and a signal analyzer 8; an axial plunger pump flange 5 for installing an axial plunger pump 6 is fixed on the test bed; the plurality of acceleration sensors comprise an X-axis acceleration sensor 4, a Y-axis acceleration sensor 3 and a Z-axis acceleration sensor 2 which are electrically connected with a charge amplifier 7; the charge amplifier 7 is electrically connected to the signal analyzer 8.
Specifically, as a specific selection of the X-axis acceleration sensor 4, the Y-axis acceleration sensor 3, and the Z-axis acceleration sensor 2, the X-axis acceleration sensor 4, the Y-axis acceleration sensor 3, and the Z-axis acceleration sensor 2 are charge-type piezoelectric acceleration sensors, the measuring range is 1000g, the response frequency is 25KHz, and the accuracy is ±0.5%.
The sampling frequency of the signal analyzer 8 is 2-5 times of the response frequency of the acceleration sensor.
As a specific installation mode of the X-axis acceleration sensor 4, the Y-axis acceleration sensor 3 and the Z-axis acceleration sensor 2, the installation directions of the X-axis acceleration sensor 4 and the Y-axis acceleration sensor 3 are perpendicular to the rotation shaft of the axial plunger pump 6; the mounting direction of the Z-axis acceleration sensor 2 is parallel to the axis of rotation of the axial plunger pump 6.
The invention also provides a use method of the vibration acquisition system of the aviation high-pressure axial plunger pump, which comprises the following steps:
step S1, the axial plunger pump 6 is mounted on the axial plunger pump flange 5.
S2, starting the axial plunger pump 6, and collecting X, Y, Z axial acceleration signals of the full frequency band of the axial plunger pump 6 under different working conditions; specifically, at least three cycles are collected for each condition.
And S3, obtaining the effective values and the maximum values of the acceleration signals of the multiple sections of different frequency sections. Specifically, effective values of acceleration signals in frequency bands of 0-1000 Hz, 1000-3000 Hz, 3000-6000 Hz and 6000Hz are obtained through band-pass filtering.
The effective value calculation formula of the acceleration signal is as follows:
wherein X (T) is the instantaneous acceleration amplitude at a certain moment, T is a period time, X RMS is the effective value of acceleration in the period of T, and T is a certain moment;
the maximum value calculation formula of the acceleration signal is:
where max is the maximum sign.
And S4, comparing the effective values and the maximum values of the acceleration signals of a plurality of sections of different frequency sections to obtain components of the axial plunger pump 6 influencing the acceleration amplitude, and providing an optimization rule.
The vibration acquisition system of the aviation high-pressure axial plunger pump and the use method are applied to vibration acquisition of a certain aviation high-pressure axial plunger pump, the high-pressure axial plunger pump is provided with a buffer bottle and a buffer bottle-free type, the outlet pressure of the high-pressure axial plunger pump is 28MPa, and the test working conditions of the high-pressure axial plunger pump are shown in table 1.
Firstly, according to step S2, a Z-direction acceleration value and an X-direction acceleration value of a high-pressure axial plunger pump with a buffer bottle and a non-buffer bottle are respectively acquired through a Z-axis acceleration sensor 2 and an X-axis acceleration sensor 4; the result of the Z-direction acceleration value acquired by the Z-axis acceleration sensor 2 is shown in fig. 2; then according to step S3, obtaining the effective value of the Z-direction acceleration signal and the effective value of the X-direction acceleration signal under a plurality of sections of different frequency sections, and the results are shown in fig. 3 and 4; the effective values of the Z-direction acceleration signals of the two high-pressure axial plunger pumps with the buffer bottle and the buffer-free bottle under a plurality of different frequency segments are compared, and the results are shown in fig. 5 and 6. As can be seen from fig. 5 and fig. 6, the acceleration amplitude is very small when there is no buffer bottle in the high frequency range of 6000hz to 10000hz, the effective values of the accelerations in the high frequency ranges of 0 to 10000hz and 6000hz to 10000hz are the same, the peak-valley characteristics are the same, that is, the buffer bottle is the reason for the relatively large effective value of the acceleration of the aviation high-pressure axial plunger pump; the other components in the high-pressure axial plunger pump can be analyzed in the mode, namely, the influence of different components in the aviation high-pressure axial plunger pump on vibration is judged by extracting characteristic signals under different frequencies, and finally, the mechanism of forming faults of the axial plunger pump is obtained, so that a theoretical basis is provided for optimizing each component in the axial plunger pump.
In summary, according to the vibration acquisition system and the use method of the aviation high-pressure axial plunger pump provided by the invention, the contribution degree of each component of the aviation high-pressure axial plunger pump to vibration is judged by establishing the ground test bed 1, arranging acceleration sensors in different directions, acquiring and decomposing vibration signals in different frequency bands, and the instantaneous acceleration values, the effective values and the full-period vibration characteristics in different frequency bands can be accurately captured, so that the characteristics in the signals are extracted and analyzed, a failure formation mechanism is finally obtained, the system is suitable for working environment sounds with loud noise in an aircraft system, and the problem that a hydraulic plunger pump failure diagnosis device in the prior art cannot be suitable for the aircraft system is solved.
Claims (3)
1. The application method of the vibration acquisition system of the aviation high-pressure axial plunger pump is characterized in that the vibration acquisition system of the aviation high-pressure axial plunger pump comprises a test bed, a plurality of acceleration sensors, a charge amplifier and a signal analyzer; an axial plunger pump flange for installing the axial plunger pump is fixed on the test bed; the acceleration sensors comprise an X-axis acceleration sensor, a Y-axis acceleration sensor and a Z-axis acceleration sensor which are electrically connected with the charge amplifier; the charge amplifier is electrically connected with the signal analyzer; the installation directions of the X-axis acceleration sensor and the Y-axis acceleration sensor are perpendicular to the axial plunger pump rotating shaft; the installation direction of the Z-axis acceleration sensor is parallel to the rotation shaft of the axial plunger pump;
the using method of the vibration acquisition system of the aviation high-pressure axial plunger pump comprises the following steps:
s1, mounting an axial plunger pump on an axial plunger pump flange;
s2, starting the axial plunger pump, and collecting X, Y, Z axial acceleration signals of the full frequency band of the axial plunger pump under different working conditions; at least three cycles are collected for each working condition;
S3, obtaining effective values and maximum values of acceleration signals of multiple sections of different frequency sections; obtaining effective values of acceleration signals in frequency bands of 0-1000 Hz, 1000-3000 Hz, 3000-6000 Hz and 6000-10000 Hz through band-pass filtering, wherein the effective value calculation formula of the acceleration signals is as follows:
wherein X (T) is the instantaneous acceleration amplitude at a certain moment, T is a period time, X RMS is the effective value of acceleration in the period of T, and T is a certain moment;
the maximum value calculation formula of the acceleration signal is:
wherein max is the maximum value symbol;
and S4, comparing the effective values and the maximum values of the acceleration signals of the multiple sections of different frequency sections to obtain components of the axial plunger pump affecting the acceleration amplitude, and providing an optimization rule.
2. The method for using the vibration acquisition system of the aviation high-pressure axial plunger pump according to claim 1, wherein the X-axis acceleration sensor, the Y-axis acceleration sensor and the Z-axis acceleration sensor are charge type piezoelectric acceleration sensors, the measuring range is 1000g, the response frequency is 25KHz, and the precision is +/-0.5%.
3. The method for using the vibration acquisition system of the aviation high-pressure axial plunger pump according to claim 2, wherein the sampling frequency of the signal analyzer is 2-5 times of the response frequency of the acceleration sensor.
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CN113834563A (en) * | 2021-10-26 | 2021-12-24 | 山东大学 | Mechanical vibration state signal acquisition and analysis system |
CN116893036A (en) * | 2023-04-03 | 2023-10-17 | 中国石油天然气股份有限公司长庆油田分公司第三采油厂 | Plunger pump leakage diagnosis method with smooth acceleration signal sequence time window characteristics |
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CN113834563A (en) * | 2021-10-26 | 2021-12-24 | 山东大学 | Mechanical vibration state signal acquisition and analysis system |
CN116893036A (en) * | 2023-04-03 | 2023-10-17 | 中国石油天然气股份有限公司长庆油田分公司第三采油厂 | Plunger pump leakage diagnosis method with smooth acceleration signal sequence time window characteristics |
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