SU553376A1 - The method of determining the proportion of vibration in a complex oscillatory system from each source of vibration - Google Patents

Description

(S4) METHOD FOR DETERMINING THE SHARE OF VIBRATION FROM EVERY SOURCE OF VIBRATION IN COMPLEX VIBRATIONAL

SYSTEM

squares of modules corresponding to the measured vibration transmission coefficients from the vibration source under investigation to the system’s control point, then integrate the obtained spectra by frequency and normalize the integrator output signals, measure the ratio of the integrator's output signal to the overall system vibration level at the control point and get the vibration share.

The drawing shows a block diagram of the device that implements the proposed method.

The device contains an oscillating system 1 with acceleration sensors 2 located in the fastener of vibration sources 3, the outputs of sensors 2 are connected to the outputs of amplifiers of a multi-channel switch 4, the control input of which is connected to the output of control device 5, and the outputs of amplifiers of a multi-channel switch 4 are connected to the inputs of the multichannel device 6 for recording and reproducing vibrational processes, the outputs of which are connected to the outputs of the multichannel spectral analyzer 7. The output of the spectral the analyzer 7 is connected to the input of the device 8 of the recording of the mutual energy spectrum of vibration processes, the output of which is connected to the digital resolver 9, the other INPUT of which is connected to the output of the ycro device 10 for recording and reproducing the complex vibration transmission coefficient (VCC), the control input of which is connected to the output of the control device 5 and the other output of the control device 5 is connected to the electric vibrator 11. The switchable output of the multichannel switch 4 is connected to the input of the PDC measurement device 12. the output of which is connected to the input of the recorder KKP 10. The output of the solving device 9 is connected to one input of the multiplying device 13, the other input of which is connected to the output of the measurement device 14 of the coefficient module; transmission of vibrations, whose input is connected to the output of the device 10. Acceleration sensor output 15. located at the reference point of the system 1 is connected to the input of the amplifier of the switch 4, and the output of the integrator 16 is connected to the output of the multiplying device 13, and the output of the integrator 16 is connected to the normalization device 17, you the course of which is connected with a recording device 18.

The essence of the proposed method consists in measuring the mutual energy spectra of vibration using vibration sensors located at one or several control points of a complex oscillatory system and at the points of attachment of vibration sources, for example, using shock absorbers, taking into account the dispersion properties of the system by measuring the complex vibration transfer coefficients between the indicated points. The complex vibrational transfer coefficients are measured by applying a known external force to the system at the attachment points of the vibrating mechanisms, for example, using a vibrator, and the transmission coefficients and the phase angle between the measuring points and the force application point are measured. Further, when processing the received data, the own energy spectrum of each actual vibration source is determined, which is related through complex transmission coefficients to the directly measured vibration spectra according to the following relation;

XXV fV

G (f) Е К (f) K (f) G (f) 1tp: 1 ktp jrn mm

71

to ()) SG ()

and

i- (n,., ki

1 jtm

) where (j is the intended frequency spectrum

between i-points k and j;

Iff

  f is its own energy spectrum but the total temperature at point m (the spectrum that would have been measured at point t, if you can turn off all sources of vibration except t-th); F

- - a reciprocal spectrum of vibration sources at points I and m (a spectrum that could have been measured directly at points i and m under the condition I К (f) 0 /

Ttl

kt jrn Ki complex factors

transmissions of vibrations between points of rotation and rhenium k and m, j and rpjK and i, respectively;

n - the number of sources of vibration.

Then, having determined the energy sources own sources and the vibration transmission coefficient of the system, they determine the fraction of vibration generated by each vibration source in the overall vibration level of the mechanical oscillatory system at the control point of the system.

The method is as follows.

Claims (2)

Electrical signals from device 2 and sensor 15 are fed to the input of amplifiers of a multichannel electronic switch 4. When measuring vibrations and mutual energy spectra of vibration processes at the attachment points of vibration sources 3 and at the control point of system 1, the outputs of the amplifiers of switch 4 are fed to the inputs of a multichannel device 6 recording and playback of vibration processes. The output signals of the device 6 are fed to the inputs of the multichannel spectral analyzer 7, and to the input of the automatic frequency tuning of the analyzer 7, the high-frequency oscillators of the GZ-18 generator of the control device 5 are output. The output signals of the spectral analyzer 7 and the frequency meter of the control device 5 are fed to the inputs of the digital converter and device (UZTI) device 8 recording energy spectrum vibrationijjiOHHbrx. processes, while the output signal of the generator of the audio frequency of the device 5 is fed to the input of the frequency meter of this device, and the electronic device compares the frequency (also included in DEVICE 5) when a predetermined frequency is established. A tunable generator produces an electrical signal to the control input of the electric drive of the generator and stops the last one In the device 8 on a punched tape, the tuning frequency of the analyzer 7 and the mutual energy spectrum of the vibration processes are recorded successively in code 2-10. Next, a punched tape from the device 8 is inputted to a digital solving device 9. When measuring the PDE, the output signal of the tunable frequency generator of the device 5 serves the inputs of the electric vibrator Well, they are sequentially inputted to the points of attachment of the vibration sources 3. The output and small signal of the electronic device comparing the frequency of the device 5 is fed to the) shravel input of the multi-channel switch 4, while the signal of the switchable output of the switch 4 is fed to the input of the measuring device KKP 12, In the device 12 measuring The amplitude values and phase shifts between the reference electrical; {m accelerometer signal located at the location of the vibrator 11 and harmonic electric signals;; shw sensors, with sequential switching channels of the switch 4. The output signal, the device 12 is fed to the input of the digital converter the PCR recording and reproducing device 10, while the output pulse signal of the electro-south frequency comparison device and the output signal of the frequency meter of the control device 5 are supplied respectively to the control The input and on the UZSI device for recording and playback of the PDC 10. In device 10 on a punched tape, the frequency of the signal of the generator supplying the vibrator and the amplitude values and phase shifts between the reference signal of the sensor and the harmonic signals of other sensors, i.e. . components KKP, Next, a punched tape from the device 10 is input to the input of the decisive device 9 and to the input of the device 14 measuring the module of the transmission coefficient of vibrations from the vibration source under investigation To the reference point of the oscillating system I. The output signal of the device 9 represents the self-contained energy spectrum of the source of vibration, is fed to the input of the loyuzhnogo device 13, to another input of which is fed, the output signal from the device 14. The output signal of the multiplying device 13, representing the co6:) th energy spectrum, according to they give the input to a digital integrator (adder) 16, where the energy spectrum and} 1 oscillate in frequency. The output signal of the integrator 16 is fed to the input of the rationing device 17, to another input of which the output signal of the device b is fed, which is a signal of the overall vibration level at the control / point of the system. In device 17, the ratio of the output signal of the integrator to the overall vibration level of the system at the reference point is measured. Then the output signal of the device 17 serves on the input of the recording device 18 and receive a fraction of vibration. The advantage of the proposed method, as well as the known ones, is an increase in the TOXTH point and the elimination of errors in the determination of the vibroactivity of vibration sources due to the inclusion of cross-links between statically dependent vibration sources through the transient (admittances) of the mechanical system. Cross-links and possible Me iam-iiecKaH links between sources are learned by measuring the complex transfer coefficients of the reverse link. Method of the invention: determining the fraction of vibration from each vibration source in a complex oscillating system, which consists in measuring the vibrations and mutual energy spectra of the system vibration processes using vibration sensors that are located at the attachment points of the vibration sources to the system and at the level control points} 1 vibrations and process the received data, characterized in that, in order to improve the accuracy of determining the vibroactivity of sources, an external force is applied, varying according to a predetermined For example, according to harmonics, consistently at all points of attachment of vibration sources, the complex transmission coefficients of vibration at attachment points relative to vibration at the point of application of force are measured, and the own energy spectra of each vibration source are determined by processing the obtained data, then multiplying these spectra by squares of the modules of the corresponding measured vibration transmission coefficients from the vibration source under investigation to the system control point, after which the field is integrated the frequency spectra are scientifically and normalize the output signals of the integrators, measure the ratio of the integrator's output signal to the total system vibration of the system at the control point and get the vibration share. Sources of information taken into account in the examination: 1. I ASA volj27.1955, p. 236-246. 2. Genkin Mod., Application of the code method to the calculation of the dynamic characteristics of mechanical systems under conditions of their normal operation. - Sat. Vibroacoustic activity of me; kanizm with gears, 1971, p.205-pro1-type,