CN115575121B - Construction method of rolling bearing dynamic model - Google Patents
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- CN115575121B CN115575121B CN202211171884.8A CN202211171884A CN115575121B CN 115575121 B CN115575121 B CN 115575121B CN 202211171884 A CN202211171884 A CN 202211171884A CN 115575121 B CN115575121 B CN 115575121B
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- G01M13/00—Testing of machine parts
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Abstract
The invention belongs to the technical field of dynamic modeling, in particular to a method for constructing a rolling bearing dynamic model, which comprises the following steps: step one: collecting data information of the rolling bearing, and detecting defects of the rolling bearing by utilizing an ultrasonic flaw detection technology; step two: analyzing the movement resistance of the rolling bearing according to the data information of the rolling bearing; step three: according to the defects and the motion resistance of the rolling bearing, introducing corresponding displacement excitation into a two-degree-of-freedom dynamic model, and establishing a rolling bearing periodic dynamic model; step four: according to the rolling bearing periodic dynamics model, a amplitude-frequency response curve of system variable compliance vibration is obtained, the influence of defects and resistance of the rolling bearing on the rolling bearing dynamics characteristics is analyzed, difference data are obtained, the difference data are combined with the rolling bearing periodic dynamics model, a new mechanical model is obtained, the influence of the defects and resistance of the rolling bearing on the bearing mechanical model can be effectively analyzed, and actual mechanical model data are obtained.
Description
Technical Field
The invention relates to the technical field of dynamic modeling, in particular to a method for constructing a rolling bearing dynamic model.
Background
Rolling bearings (Rolling bearings) are a precision mechanical element that changes sliding friction between an operating shaft and a shaft seat into Rolling friction, thereby reducing friction losses. The rolling bearing generally consists of four parts, namely an inner ring, an outer ring, rolling bodies and a retainer, wherein the inner ring is matched with the shaft and rotates together with the shaft; the outer ring is matched with the bearing seat to play a supporting role; the rolling bodies uniformly transfer external load between the inner ring and the outer ring by means of the retainer, and the shape, the size and the number of the rolling bodies directly influence the service performance and the service life of the rolling bearing; the retainer can uniformly distribute the rolling bodies along the rollaway nest and guide the rolling bodies to roll, and part of the retainer can also play a role in lubrication; the bearing dynamics modeling is a convenient and effective means for predicting and simulating the performance of the bearing system such as vibration acceleration response, and compared with the traditional experimental method, the bearing dynamics modeling has the advantage of short period, and meanwhile, the experimental cost can be greatly saved.
At present, when a mechanical model is modeled on a rolling bearing, the influence of cracks and movement resistance of the rolling bearing on the rolling bearing is not brought, the obtained data is only theoretical data, and the actual mechanical model data cannot be obtained.
Disclosure of Invention
This section is intended to outline some aspects of embodiments of the invention and to briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section as well as in the description summary and in the title of the application, to avoid obscuring the purpose of this section, the description summary and the title of the invention, which should not be used to limit the scope of the invention.
The present invention has been made in view of the above and/or problems occurring in the construction of dynamic models of existing rolling bearings.
Therefore, the invention aims to provide a method for constructing a rolling bearing dynamic model, which is characterized in that before a mechanical model is constructed, defects and movement resistance of a rolling bearing are analyzed, then a rolling bearing periodic dynamic model is established according to data information of the rolling bearing, influences of the defects and the resistance of the rolling bearing on dynamic characteristics of the rolling bearing are analyzed to obtain difference data, the difference data is combined with the rolling bearing periodic dynamic model to obtain a new mechanical model, and the influence of the self resistance of the rolling bearing on the mechanical model can be effectively analyzed to obtain actual mechanical model data.
In order to solve the technical problems, according to one aspect of the present invention, the following technical solutions are provided:
the construction method of the rolling bearing dynamic model comprises the following steps:
step one: collecting data information of the rolling bearing, and detecting defects of the rolling bearing by utilizing an ultrasonic flaw detection technology;
step two: analyzing the movement resistance of the rolling bearing according to the data information of the rolling bearing;
step three: according to the defects and the motion resistance of the rolling bearing, introducing corresponding displacement excitation into a two-degree-of-freedom dynamic model, and establishing a rolling bearing periodic dynamic model;
step four: according to the periodic dynamic model of the rolling bearing, an amplitude-frequency response curve of the system variable compliance vibration is obtained;
step five: substituting the defects and the resistance of the rolling bearing into a rolling bearing periodic dynamics model, analyzing the influence of the defects and the resistance of the rolling bearing on the dynamic characteristics of the rolling bearing, and obtaining difference data;
step six: and combining the difference data with the rolling bearing periodic dynamics model to obtain a new mechanical model.
As a preferred embodiment of the method for constructing a dynamic model of a rolling bearing according to the present invention, there is provided: in the first step, the data information of the rolling bearing comprises the geometric dimensions of the inner and outer ring raceways, the size and the number of the rolling bodies, the toughness, the rigidity and the equivalent damping of the material.
As a preferred embodiment of the method for constructing a dynamic model of a rolling bearing according to the present invention, there is provided: in the first step, crack detection is carried out on the inner and outer ring raceways of the rolling bearing by an ultrasonic flaw detector.
As a preferred embodiment of the method for constructing a dynamic model of a rolling bearing according to the present invention, there is provided: in the second step, the movement resistance is derived from the friction resistance of the rolling bodies during movement, the damping between materials and the blocking force of the raceway cracks on the movement of the rolling bodies.
As a preferred embodiment of the method for constructing a dynamic model of a rolling bearing according to the present invention, there is provided: in the third step, data of the rolling bearing is input into a two-degree-of-freedom rolling bearing variable compliance vibration equation, and a radial variable compliance vibration dynamics model of the rolling bearing system is established.
As a preferred embodiment of the method for constructing a dynamic model of a rolling bearing according to the present invention, there is provided: in the fourth step, a mechanical model of the rolling bearing is obtained by adopting a harmonic balance-frequency/time conversion method, so as to obtain a variable-flexibility vibration main resonance amplitude-frequency response curve.
As a preferred embodiment of the method for constructing a dynamic model of a rolling bearing according to the present invention, there is provided: and fifthly, analyzing the defects and the resistance of the rolling bearing, and obtaining a mechanical resistance curve of the bearing according to the defects and the resistance parameters of the bearing.
As a preferred embodiment of the method for constructing a dynamic model of a rolling bearing according to the present invention, there is provided: in the sixth step, the new mechanical model is the actual kinematic mechanical model obtained by subtracting the difference value caused by the defects and the resistance in the motion from the theoretical mechanical data of the rolling bearing.
Compared with the prior art: according to the invention, before a mechanical model is constructed, the defects and the movement resistance of the rolling bearing are analyzed, then a rolling bearing periodic dynamics model is established according to the data information of the rolling bearing, the influence of the defects and the resistance of the rolling bearing on the dynamic characteristics of the rolling bearing is analyzed, difference data are obtained, the difference data are combined with the rolling bearing periodic dynamics model to obtain a new mechanical model, the influence of the defects and the resistance of the rolling bearing on the bearing mechanical model can be effectively analyzed, and actual mechanical model data are obtained.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following detailed description of the embodiments of the present invention will be given with reference to the accompanying drawings, which are to be understood as merely some embodiments of the present invention, and from which other drawings can be obtained by those skilled in the art without inventive faculty. Wherein:
FIG. 1 is a schematic diagram of the flow structure of the steps of the present invention.
Detailed Description
In order that the above objects, features and advantages of the invention will be readily understood, a more particular description of the invention will be rendered by reference to the appended drawings.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways other than those described herein, and persons skilled in the art will readily appreciate that the present invention is not limited to the specific embodiments disclosed below.
Next, the present invention will be described in detail with reference to the drawings, wherein the sectional view of the device structure is not partially enlarged to general scale for the convenience of description, and the drawings are only examples, which should not limit the scope of the present invention. In addition, the three-dimensional dimensions of length, width and depth should be included in actual fabrication.
For the purpose of making the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.
The invention provides a method for constructing a rolling bearing dynamic model, which comprises the steps of analyzing defects and motion resistance of a rolling bearing before constructing a mechanical model, then establishing a rolling bearing periodic dynamic model according to data information of the rolling bearing, analyzing the influence of the defects and the resistance of the rolling bearing on dynamic characteristics of the rolling bearing to obtain difference data, combining the difference data with the rolling bearing periodic dynamic model to obtain a new mechanical model, and effectively analyzing the influence of the defects and the resistance of the rolling bearing on the bearing mechanical model to obtain actual mechanical model data, wherein the method comprises the following steps of referring to FIG. 1:
step one: data information of the rolling bearing is collected, and defects of the rolling bearing are detected by utilizing an ultrasonic flaw detection technology.
Step two: the motion resistance of the rolling bearing is analyzed according to the data information of the rolling bearing, and the influence of surface cracks on the tribological performance of the rolling bearing is studied through commercial software ANSYS based on the fluid-solid coupling technology. And respectively establishing a fluid-solid coupling finite element model of the sliding bearing with cracks of different section types, different distribution positions and different opening directions, and analyzing the influence of surface cracks on the maximum oil film pressure, bearing capacity, friction force and friction coefficient of the sliding bearing. The research results show that: the presence of surface cracks results in a reduction of the maximum oil film pressure of the sliding bearing; and the bearing capacity and the friction coefficient of the sliding bearing are obviously influenced, and the influence degree of the bearing capacity and the friction coefficient are closely related to the crack section type, the distribution position and the opening direction.
Step three: according to the defects and the motion resistance of the rolling bearing, corresponding displacement excitation is introduced into a two-degree-of-freedom dynamic model, a rolling bearing periodic dynamic model is built, the rolling bearing dynamic model is researched and subjected to three stages of hydrostatic analysis quasi-dynamic analysis and dynamic analysis, and the quasi-dynamic analysis model can solve the analysis of the motion parameters of the bearing and basically meet engineering requirements.
Step four: according to the periodic dynamic model of the rolling bearing, an amplitude-frequency response curve of the system variable compliance vibration is obtained; the curve drawn by the ratio of various different signals is called an amplitude-frequency response curve, the phase difference between the phase of the output signal after the signal passes through the system and the phase value of the signal when the output signal is input is called phase-frequency response, a signal amplifier is often used in the process of processing the input signal, the amplitude and the phase of the output signal of an amplifying circuit can change along with the change of the frequency of the signal, and generally, the amplitude of the signal is reduced and a certain phase shift is generated in the low frequency band, the high frequency band and the medium frequency band of the amplifying circuit. The frequency characteristic of the amplifying circuit is divided into amplitude-frequency characteristic and phase-frequency characteristic, wherein the amplitude-frequency characteristic is a law of describing that the amplitude of an input signal is fixed and the amplitude of an output signal changes along with the change of frequency, namely, au (j omega) =v0Viej phi=Au (omega) ej phi (omega) in the formula, au (omega) represents the relation between the magnitude of voltage amplification factor and the frequency, and the amplitude-frequency characteristic is called.
Step five: substituting the defects and the resistance of the rolling bearing into a rolling bearing periodic dynamics model, analyzing the influence of the defects and the resistance of the rolling bearing on the dynamic characteristics of the rolling bearing, and obtaining difference data;
step six: and combining the difference data with the rolling bearing periodic dynamics model to obtain a new mechanical model.
In the first step, the data information of the rolling bearing comprises the geometric dimensions of the inner and outer ring raceways, the number of rolling bodies, the toughness, the rigidity and the equivalent damping of the material.
In the first step, crack detection is carried out on the inner and outer ring raceways of the rolling bearing by an ultrasonic flaw detector.
In the second step, the movement resistance is derived from the friction resistance of the rolling elements during movement, the damping between materials and the blocking force of the raceway cracks on the movement of the rolling elements.
And thirdly, inputting data of the rolling bearing into a two-degree-of-freedom rolling bearing variable compliance vibration equation, and establishing a radial variable compliance vibration dynamics model of the rolling bearing system.
And step four, adopting a mechanical model of the rolling bearing by a harmonic balance-frequency/time conversion method to obtain a variable-flexibility vibration main resonance amplitude-frequency response curve.
And fifthly, analyzing the defects and the resistance of the rolling bearing, and obtaining a mechanical resistance curve of the bearing according to the defects and the resistance parameters of the bearing.
And step six, the new mechanical model is the actual kinematic mechanical model obtained by subtracting the difference value caused by the defects and the resistance in the motion from the theoretical mechanical data of the rolling bearing.
According to the steps one to six, the influences of the defects and the resistance of the rolling bearing on the dynamic characteristics of the rolling bearing are analyzed to obtain difference data, the difference data are combined with the periodic dynamic model of the rolling bearing to obtain a new mechanical model, and the influences of the defects and the resistance of the rolling bearing on the mechanical model of the rolling bearing can be effectively analyzed to obtain actual mechanical model data.
Although the invention has been described hereinabove with reference to embodiments, various modifications thereof may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In particular, the features of the disclosed embodiments may be combined with each other in any manner as long as there is no structural conflict, and the exhaustive description of these combinations is not given in this specification merely for the sake of omitting the descriptions and saving resources. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.
Claims (8)
1. The construction method of the rolling bearing dynamic model is characterized by comprising the following steps of:
step one: collecting data information of the rolling bearing, and detecting defects of the rolling bearing by utilizing an ultrasonic flaw detection technology;
step two: analyzing the movement resistance of the rolling bearing according to the data information of the rolling bearing;
step three: according to the defects and the motion resistance of the rolling bearing, introducing corresponding displacement excitation into a two-degree-of-freedom dynamic model, and establishing a rolling bearing periodic dynamic model;
step four: according to the periodic dynamic model of the rolling bearing, an amplitude-frequency response curve of the system variable compliance vibration is obtained;
step five: substituting the defects and the motion resistance of the rolling bearing into a rolling bearing periodic dynamics model, analyzing the influence of the defects and the motion resistance of the rolling bearing on the dynamic characteristics of the rolling bearing, and obtaining difference data;
step six: and combining the difference data with the rolling bearing periodic dynamics model to obtain a new mechanical model.
2. The method of claim 1, wherein in the first step, the data information of the rolling bearing includes geometry of inner and outer race tracks, size and number of rolling elements, toughness of material, rigidity and equivalent damping.
3. The method of claim 1, wherein in the first step, crack detection is performed on the inner and outer race tracks of the rolling bearing by using an ultrasonic flaw detector.
4. The method of claim 1, wherein in the second step, the motion resistance is derived from frictional resistance during the movement of the rolling elements, damping between materials, and a resistance of the raceway crack to the movement of the rolling elements.
5. The method for constructing a dynamic model of a rolling bearing according to claim 1, wherein in the third step, data of the rolling bearing is input into a two-degree-of-freedom rolling bearing variable compliance vibration equation, and a radial variable compliance vibration dynamic model of the rolling bearing system is established.
6. The method for constructing a dynamic model of a rolling bearing according to claim 1, wherein in the fourth step, a dynamic model of the rolling bearing by a harmonic balance-frequency/time conversion method is adopted to obtain a variable compliance vibration main resonance amplitude-frequency response curve.
7. The method for constructing a dynamic model of a rolling bearing according to claim 1, wherein in the fifth step, defects and movement resistance of the rolling bearing are analyzed, and a mechanical resistance curve of the bearing is obtained according to the defects and movement resistance parameters of the bearing.
8. The method according to claim 1, wherein in the sixth step, the new mechanical model is a theoretical mechanical data of the rolling bearing subtracted by a difference value caused by a defect and a resistance during movement to obtain an actual kinetic mechanical model.
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| CN103712785B (en) * | 2013-09-12 | 2017-01-04 | 西安交通大学 | A kind of rolling bearing rotor-support-foundation system damage vibratory response quantitative calculation method |
| CN106126850A (en) * | 2016-07-04 | 2016-11-16 | 湖南科技大学 | A kind of rolling bearing surface damage faulty power modeling method |
| CN109946077B (en) * | 2019-02-15 | 2021-04-20 | 南昌航空大学 | Method for establishing fractional order damping rolling bearing fault dynamics gradual model |
| CN113092115B (en) * | 2021-04-09 | 2022-10-11 | 重庆大学 | Digital twin model construction method of digital-analog combined drive full-life rolling bearing |
| CN113567132B (en) * | 2021-09-01 | 2022-10-21 | 郑州轻工业大学 | Motor rolling bearing fault model construction method based on digital twinning technology |
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