Conversion method for equipment vibration parameters in different installation states

Abstract

The invention provides a conversion method for equipment vibration parameters in different installation states, and relates to the technical field of equipment vibration noise test and analysis. The conversion method comprises the following steps: acquiring machine foot admittance of equipment; the original point admittance of the input end of each vibration isolator, the original point admittance of the output end of each vibration isolator, the transmission admittance of the input end of each vibration isolator and the transmission admittance of the output end of each vibration isolator are obtained; obtaining the free vibration velocity of the equipment; the actual installation base admittance is obtained; according to the free vibration velocity, the machine foot admittance, the original point admittance of the input end of the vibration isolator, the original point admittance of the output end of the vibration isolator, the transmission admittance of the input end of the vibration isolator, the transmission admittance of the output end of the vibration isolator and the admittance of the actual installation base, vibration parameters of the equipment installed on the actual installation base are calculated. According to the method, the invariance of the free vibration velocity of the equipment installed in different environments is considered, the conversion relation of the exciting force of the equipment on different bases is established, the required result is calculated, and accurate prediction of the excitation characteristics of the equipment in different installation environments is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of equipment vibration noise testing and analysis, and in particular to a method for converting equipment vibration parameters under different installation states. Background Art

[0002] Mechanical equipment is an important source of vibration and noise in engineering projects. Its vibration will have adverse effects on the surrounding environment, such as reducing system operation stability and personnel comfort. Therefore, many engineering projects have put forward control requirements for the vibration of mechanical equipment.

[0003] At present, the evaluation of mechanical equipment vibration is mainly carried out on the standard equipment bench at the factory stage to obtain the vibration characteristics of the equipment. However, the vibration characteristics of mechanical equipment are closely related to its installation environment. Due to different boundary conditions in different installation environments, the vibration characteristics of mechanical equipment will also be different. Therefore, the factory vibration test results of mechanical equipment cannot directly reflect the vibration characteristics of the equipment after being installed in the actual operating environment, which may pose certain safety hazards.

[0004] Therefore, in order to accurately obtain the vibration characteristics of mechanical equipment in the actual installation environment, how to propose a method for converting the vibration parameters of equipment under different installation conditions has become a technical problem that needs to be solved urgently. Summary of the invention

[0005] In view of this, the present invention provides a measurement method capable of accurately obtaining the vibration characteristics of mechanical equipment in an actual installation environment.

[0006] Specifically, the present invention is achieved through the following technical solutions:

[0007] According to a first aspect of the present invention, there is provided a method for converting vibration parameters of a device under different installation states, comprising: placing the device in a free suspension state, arranging an acceleration sensor on each machine foot of the device, and tapping each machine foot in turn with an excitation hammer to obtain the machine foot admittance of the device; obtaining the origin admittance of each vibration isolator input end, the origin admittance of the vibration isolator output end, the transfer admittance of the vibration isolator input end, and the transfer admittance of the vibration isolator output end; obtaining the free vibration speed of the device; installing the device on an actual installation base, and arranging an acceleration sensor at each installation point of the actual installation base, and tapping each installation point of the actual installation base in turn with an excitation hammer to obtain the actual installation base admittance; calculating the vibration parameters of the device installed on the actual installation base according to the free vibration speed, the machine foot admittance, the origin admittance of the vibration isolator input end, the origin admittance of the vibration isolator output end, the transfer admittance of the vibration isolator input end, the transfer admittance of the vibration isolator output end, and the actual installation base admittance.

[0008] In some embodiments, the step of obtaining the free vibration velocity of the device includes: arranging an acceleration sensor at each mounting point of a standard base of a standard test bench, and tapping each mounting point of the standard base in turn with an excitation hammer to obtain the standard base admittance; installing the device on the standard base of the standard test bench; arranging a velocity sensor on each machine foot of the device, turning on the device, and obtaining the machine foot speed of the device on the standard test bench; and calculating the free vibration velocity of the device based on the standard base admittance, the machine foot speed, the origin admittance of the isolator input end, the origin admittance of the isolator output end, the transfer admittance of the isolator input end, the transfer admittance of the isolator output end, and the machine foot admittance.

[0009] In some embodiments, the free vibration velocity of the device is calculated based on the standard base admittance, the machine foot speed, the origin admittance of the isolator input end, the origin admittance of the isolator output end, the transfer admittance of the isolator input end, the transfer admittance of the isolator output end and the machine foot admittance, and the following formula is used for calculation:

[0010] K=(Y S +Y 11 )Y 21 -1 (Y R +Y 22 )-Y 12 ;

[0011] v0=K[Y 11 Y 21 -1 (Y R +Y 22 )-Y 12 ] -1 v1;

[0012] Where v0 represents the free vibration velocity of the equipment, Y 11 represents the origin admittance of the isolator input end, Y 22 represents the origin admittance of the isolator output end, Y 12 represents the transfer admittance at the input end of the isolator, Y 21 represents the transfer admittance at the output end of the vibration isolator, v1 represents the speed of the equipment on the standard stand, and Y R represents the standard base admittance, Y S represents the foot admittance of the equipment, and K represents the transfer admittance matrix when the equipment is installed on a standard base.

[0013] In some embodiments, the step of obtaining the free vibration velocity of the device includes: placing the device in a free hanging state, turning on the device, and directly measuring the free vibration velocity of the device.

[0014] In some embodiments, the step of obtaining the origin admittance of each isolator input end, the origin admittance of the isolator output end, the transfer admittance of the isolator input end, and the transfer admittance of the isolator output end includes: measuring the impedance parameters of the isolator; and using the impedance parameters to convert the origin admittance of the isolator input end, the origin admittance of the isolator output end, the transfer admittance of the isolator input end, and the transfer admittance of the isolator output end.

[0015] In some embodiments, the vibration parameters include at least one of a machine foot vibration velocity at the upper end of the vibration isolator on the actual mounting base, an excitation force at the upper end of the vibration isolator on the actual mounting base, a mounting point vibration velocity at the lower end of the vibration isolator on the actual mounting base, and an excitation force at the lower end of the vibration isolator on the actual mounting base.

[0016] In some embodiments, the vibration velocity of the machine foot at the upper end of the vibration isolator on the actual mounting base is calculated according to the free vibration velocity, the machine foot admittance, the origin admittance of the isolator input end, the origin admittance of the isolator output end, the transfer admittance of the isolator input end, the transfer admittance of the isolator output end and the actual mounting base admittance, and the following formula is used for calculation:

[0017] K′=(Y S +Y 11 )Y 21 -1 (Y′ R +Y 22 )-Y 12 ;

[0018] v′1=[Y 11 Y 21 -1 (Y′ R +Y 22 )-Y 12 ][K′] -1 v0;

[0019] Where K′ represents the transfer admittance matrix when the device is installed on the actual installation base, Y S Indicates the foot admittance of the equipment, Y 11 represents the origin admittance of the isolator input end, Y 22 represents the origin admittance of the isolator output end, Y 12 represents the transfer admittance at the input end of the isolator, Y 21 represents the transfer admittance at the output end of the vibration isolator, v0 represents the free vibration velocity of the equipment, and Y′ R represents the actual installation base admittance; v′1 represents the machine foot vibration velocity at the upper end of the vibration isolator on the actual installation base.

[0020] In some embodiments, the excitation force at the upper end of the vibration isolator on the actual mounting base is calculated based on the free vibration speed, the machine foot admittance, the origin admittance of the vibration isolator input end, the origin admittance of the vibration isolator output end, the transfer admittance of the vibration isolator input end, the transfer admittance of the vibration isolator output end and the actual mounting base admittance, and the following formula is used for calculation:

[0021] K′=(Y S +Y 11 )Y 21 -1 (Y′ R +Y 22 )-Y 12 ;

[0022] F′1=Y 21 -1 (Y′ R +Y 22 )[K′] -1 v0;

[0023] Where K′ represents the transfer admittance matrix when the device is installed on the actual installation base, Y S Indicates the foot admittance of the equipment, Y 11 represents the origin admittance of the isolator input end, Y 22 represents the origin admittance of the isolator output end, Y 12 represents the transfer admittance at the input end of the isolator, Y 21 represents the transfer admittance at the output end of the vibration isolator, v0 represents the free vibration velocity of the equipment, and Y′ R represents the actual installation base admittance; F′1 represents the excitation force at the upper end of the isolator on the actual installation base.

[0024] In some embodiments, the vibration velocity of the mounting point at the lower end of the vibration isolator on the actual mounting base is calculated based on the free vibration velocity, the machine foot admittance, the origin admittance of the vibration isolator input end, the origin admittance of the vibration isolator output end, the transfer admittance of the vibration isolator input end, the transfer admittance of the vibration isolator output end and the actual mounting base admittance, and the following formula is used for calculation:

[0025] K′=(Y S +Y 11 )Y 21 -1 (Y′ R +Y 22 )-Y 12 ;

[0026] v′2=Y′ R [K′] -1 v0;

[0027] Where K′ represents the transfer admittance matrix when the device is installed on the actual installation base, Y SIndicates the foot admittance of the equipment, Y 11 represents the origin admittance of the isolator input end, Y 22 represents the origin admittance of the isolator output end, Y 12 represents the transfer admittance at the input end of the isolator, Y 21 represents the transfer admittance at the output end of the vibration isolator, v0 represents the free vibration velocity of the equipment, and Y′ R represents the actual installation base admittance; v′2 represents the vibration velocity of the installation point at the lower end of the isolator on the actual installation base.

[0028] In some embodiments, the excitation force at the lower end of the vibration isolator on the actual mounting base is calculated based on the free vibration speed, the machine foot admittance, the origin admittance of the vibration isolator input end, the origin admittance of the vibration isolator output end, the transfer admittance of the vibration isolator input end, the transfer admittance of the vibration isolator output end and the actual mounting base admittance, and the following formula is used for calculation:

[0029] K′=(Y S +Y 11 )Y 21 -1 (Y′ R +Y 22 )-Y 12 ;

[0030] F′2=-[K′] -1 v0;

[0031] Where K′ represents the transfer admittance matrix when the device is installed on the actual installation base, Y S Indicates the foot admittance of the equipment, Y 11 represents the origin admittance of the isolator input end, Y 22 represents the origin admittance of the isolator output end, Y 12 represents the transfer admittance at the input end of the isolator, Y 21 represents the transfer admittance at the output end of the vibration isolator, v0 represents the free vibration velocity of the equipment, and Y′ R represents the actual installation base admittance; F′2 represents the excitation force at the lower end of the isolator on the actual installation base.

[0032] The technical solution provided by the present invention brings at least the following beneficial effects: In the solution of the present application, taking into account the invariance of the free vibration velocity of the equipment when it is installed in different environments, that is, when it is installed on different bases, a conversion relationship between the excitation force of the equipment on different bases, the vibration of the machine feet and the standard bench is established, which provides a relatively complete and feasible conversion scheme for the measurement of the vibration parameters of the equipment. Without directly measuring the vibration parameters of the equipment, the required results can be calculated with the help of relevant intermediate data, thereby realizing accurate prediction of the excitation characteristics (vibration parameters) of the mechanical equipment under different installation environments. At the same time, on the basis of the traditional standard bench test, only the free suspension test of the mechanical equipment and the admittance test of the actual installation base are added, so as to predict the vibration characteristics of the mechanical equipment in the actual installation environment, which is simple to operate and has good prediction effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or related technical descriptions are briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0035] Figure 1 One of the flow charts of the method for converting vibration parameters of equipment under different installation states provided by an embodiment of the present invention;

[0036] Figure 2 A second flow chart of a method for converting vibration parameters of equipment under different installation states provided by an embodiment of the present invention;

[0037] Figure 3 A schematic diagram of a mechanical equipment vibration isolation system provided by an embodiment of the present invention;

[0038] Figure 4 One of the comparison diagrams of the calculated value and the measured value of the free vibration velocity v0 provided in the embodiment of the present invention;

[0039] Figure 5 The second comparison diagram of the calculated value and the measured value (one-third octave band) of the free vibration velocity v0 provided in the embodiment of the present invention;

[0040] Figure 6 A comparison chart of the predicted value and the measured value of the excitation force F′1 at the upper end of the vibration isolator provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] See also Figure 1 The embodiment of the present invention provides a method for converting vibration parameters of equipment under different installation states, comprising the following steps:

[0043] S102, placing the device in a free hanging state, arranging an acceleration sensor on each foot of the device, and using an excitation hammer to strike each foot in turn to obtain the admittance of the foot of the device.

[0044] S104, obtaining the origin admittance of each vibration isolator input end, the origin admittance of the vibration isolator output end, the transfer admittance of the vibration isolator input end, and the transfer admittance of the vibration isolator output end.

[0045] S106. Obtain the free vibration velocity of the device.

[0046] S108, arranging an acceleration sensor at each installation point of the actual installation base, and using an excitation hammer to sequentially strike each installation point of the actual installation base to obtain the admittance of the actual installation base.

[0047] S110. Calculate vibration parameters of the device installed on the actual mounting base based on the free vibration speed, the machine foot admittance, the origin admittance of the isolator input end, the origin admittance of the isolator output end, the transfer admittance of the isolator input end, the transfer admittance of the isolator output end and the admittance of the actual mounting base.

[0048] According to a method for converting vibration parameters of equipment under different installation states provided by the present invention, the equipment includes mechanical equipment, and a common mechanical equipment vibration isolation system consists of three parts: mechanical equipment, vibration isolation device and base. The mechanical equipment is used as a vibration source, and the excitation generated is transmitted to the vibration isolation device through the contact point between the mechanical equipment and the vibration isolation device, and then transmitted to the base structure through the contact point between the vibration isolation device and the base, causing the base structure to vibrate. By obtaining the machine foot admittance of the equipment, various admittances of the vibration isolator, the free vibration velocity of the equipment, and the admittance of the actual installation base, the vibration parameters of the equipment can be finally calculated based on these acquired data. In the scheme of the present application, considering the invariance of the free vibration velocity of the equipment when it is installed in different environments, that is, when it is installed on different bases, a conversion relationship between the excitation force of the equipment on different bases and the standard bench is established, which provides a relatively complete and feasible conversion scheme for the measurement of the vibration parameters of the equipment. The required results can be calculated with the help of relevant intermediate data without directly measuring the vibration parameters of the equipment, thereby realizing the accurate prediction of the excitation characteristics (vibration parameters) of the mechanical equipment under different installation environments. At the same time, on the basis of the traditional standard bench test, only the free suspension test of the mechanical equipment and the admittance test of the actual installation base are added to predict the vibration characteristics of the mechanical equipment in the actual installation environment. The operation is simple and the prediction effect is good.

[0049] In some embodiments, Figure 2 As shown, step S106, the step of obtaining the free vibration velocity of the device, includes:

[0050] S202, arranging an acceleration sensor at each installation point of a standard base of the standard test bench, and using an excitation hammer to knock each installation point of the standard base in turn to obtain the admittance of the standard base.

[0051] S204. Install the equipment on a standard base of a standard stand.

[0052] S206: Arrange a speed sensor on each machine foot of the device, turn on the device, and obtain the machine foot speed of the device on the standard stand.

[0053] S208. Calculate the free vibration speed of the equipment according to the standard base admittance, the machine foot speed, the origin admittance of the vibration isolator input end, the origin admittance of the vibration isolator output end, the transfer admittance of the vibration isolator input end, the transfer admittance of the vibration isolator output end and the machine foot admittance.

[0054] In this embodiment, by arranging an acceleration sensor at each installation point of the standard base, and then using an excitation hammer to knock on each installation point of the standard base in turn, the standard base admittance can be obtained. Next, the device is installed on the standard base of the standard bench. The standard bench refers to the standard platform used by the manufacturer to test the device at the factory stage. By arranging a speed sensor on each foot of the device, the speed of the foot of the device on the standard bench can be obtained when the device is turned on. Then, based on these data, the free vibration velocity of the device is calculated according to a specific formula, making the process of obtaining the free vibration velocity more specific and operational, improving the accuracy and repeatability of measuring the free vibration velocity, and laying a more reliable foundation for the subsequent accurate calculation of the vibration parameters of the equipment.

[0055] In some embodiments, the free vibration velocity of the device is calculated based on the standard base admittance, the machine foot speed, the origin admittance of the isolator input end, the origin admittance of the isolator output end, the transfer admittance of the isolator input end, the transfer admittance of the isolator output end and the machine foot admittance, and the following formula is used for calculation:

[0056] K=(Y S +Y 11 )Y 21 -1 (Y R +Y 22 )-Y 12 ;

[0057] v0=K[Y 11 Y 21 - 1 (Y R +Y 22 )-Y 12 ] -1 v1;

[0058] Where v0 represents the free vibration velocity of the equipment, Y 11 represents the origin admittance of the isolator input end, Y 22 represents the origin admittance of the isolator output end, Y 12 represents the transfer admittance at the input end of the isolator, Y 21 represents the transfer admittance at the output end of the vibration isolator, v1 represents the speed of the equipment on the standard stand, and Y R represents the standard base admittance, Y S represents the foot admittance of the equipment, and K represents the transfer admittance matrix when the equipment is installed on a standard base.

[0059] In some embodiments, the step of obtaining the free vibration velocity of the device includes: placing the device in a free hanging state, turning on the device, and directly measuring the free vibration velocity of the device.

[0060] In this embodiment, a method for obtaining the free vibration velocity of the device is provided. The device can be a small device. When the small device is in a free hanging state, the device is directly turned on for direct measurement. An accelerometer can be used to measure the acceleration of the device vibration, and then the velocity signal is obtained by integration. A laser Doppler vibrometer can also be used for direct measurement. The present application increases the flexibility and applicability of the method for measuring the free vibration velocity of the device so as to better adapt to various mechanical devices and measurement scenarios.

[0061] In some embodiments, the step of obtaining the origin admittance of each isolator input end, the origin admittance of the isolator output end, the transfer admittance of the isolator input end, and the transfer admittance of the isolator output end includes: measuring the impedance parameters of the isolator; and using the impedance parameters to convert the origin admittance of the isolator input end, the origin admittance of the isolator output end, the transfer admittance of the isolator input end, and the transfer admittance of the isolator output end.

[0062] In this embodiment, the input end of the vibration isolator refers to the end where the vibration is transmitted to the vibration isolator, and the origin admittance refers to a relationship between the response (output vibration condition) and the excitation at the excitation (input vibration) point. The input end of the vibration isolator refers to the end that transmits the vibration, that is, the end that inputs the vibration. The transfer admittance of the input end of the vibration isolator refers to the physical quantity that measures the relationship between the input excitation force and the vibration response at the output position of the vibration isolator at the input position of the vibration isolator. The transfer admittance of the output end of the vibration isolator refers to the relationship between the output vibration response (such as displacement, velocity or acceleration) and the excitation force applied to the input end of the vibration isolator on the output side of the vibration isolator. By measuring the impedance parameters of the vibration isolator and using them to convert them to obtain the required admittance, the way to obtain the relevant admittance of the vibration isolator is clearer and clearer, providing an accurate data source for the subsequent calculation of the vibration parameters of the equipment based on these admittance data, ensuring the data integrity and accuracy of the entire conversion method.

[0063] In some embodiments, the vibration parameters include at least one of a machine foot vibration velocity at the upper end of the vibration isolator on the actual mounting base, an excitation force at the upper end of the vibration isolator on the actual mounting base, a mounting point vibration velocity at the lower end of the vibration isolator on the actual mounting base, and an excitation force at the lower end of the vibration isolator on the actual mounting base.

[0064] In this embodiment, the upper end of the vibration isolator on the actual mounting base is that end close to the equipment, and the lower end of the vibration isolator on the mounting base is that end close to the actual mounting base. The vibration velocity of the machine foot at the upper end of the vibration isolator on the actual mounting base is that of the machine foot of the equipment, and the vibration velocity of the installation point at the lower end of the vibration isolator on the actual mounting base is that of the installation point of the vibration isolator.

[0065] In some embodiments, the vibration velocity of the machine foot at the upper end of the vibration isolator on the actual mounting base is calculated according to the free vibration velocity, the machine foot admittance, the origin admittance of the isolator input end, the origin admittance of the isolator output end, the transfer admittance of the isolator input end, the transfer admittance of the isolator output end and the actual mounting base admittance, and the following formula is used for calculation:

[0066] K′=(Y S +Y 11 )Y 21 -1 (Y′ R +Y 22 )-Y 12 ;

[0067] v′1=[Y 11 Y 21 -1 (Y′ R +Y 22 )-Y 12 ][K′] -1 v0;

[0068] Where K′ represents the transfer admittance matrix when the device is installed on the actual installation base, Y S Indicates the foot admittance of the equipment, Y 11 represents the origin admittance of the isolator input end, Y 22 represents the origin admittance of the isolator output end, Y 12 represents the transfer admittance at the input end of the isolator, Y 21 represents the transfer admittance at the output end of the vibration isolator, v0 represents the free vibration velocity of the equipment, and Y′ R represents the actual installation base admittance; v′1 represents the machine foot vibration velocity at the upper end of the vibration isolator on the actual installation base.

[0069] In some embodiments, the excitation force at the upper end of the vibration isolator on the actual mounting base is calculated based on the free vibration speed, the machine foot admittance, the origin admittance of the vibration isolator input end, the origin admittance of the vibration isolator output end, the transfer admittance of the vibration isolator input end, the transfer admittance of the vibration isolator output end and the actual mounting base admittance, and the following formula is used for calculation:

[0070] K′=(Y S +Y 11 )Y 21 -1 (Y′ R +Y 22 )-Y 12 ;

[0071] F′1=Y 21 -1 (Y′ R +Y 22 )[K′]-1 v0;

[0072] Where K′ represents the transfer admittance matrix when the device is installed on the actual installation base, Y S Indicates the foot admittance of the equipment, Y 11 represents the origin admittance of the isolator input end, Y 22 represents the origin admittance of the isolator output end, Y 12 represents the transfer admittance at the input end of the isolator, Y 21 represents the transfer admittance at the output end of the vibration isolator, v0 represents the free vibration velocity of the equipment, and Y′ R represents the actual installation base admittance; F′1 represents the excitation force at the upper end of the isolator on the actual installation base.

[0073] In some embodiments, the vibration velocity of the mounting point at the lower end of the vibration isolator on the actual mounting base is calculated based on the free vibration velocity, the machine foot admittance, the origin admittance of the vibration isolator input end, the origin admittance of the vibration isolator output end, the transfer admittance of the vibration isolator input end, the transfer admittance of the vibration isolator output end and the actual mounting base admittance, and the following formula is used for calculation:

[0074] K′=(Y S +Y 11 )Y 21 -1 (Y′ R +Y 22 )-Y 12 ;

[0075] v′2=Y′ R [K′] -1 v0;

[0076] Where K′ represents the transfer admittance matrix when the device is installed on the actual installation base, Y S Indicates the foot admittance of the equipment, Y 11 represents the origin admittance of the isolator input end, Y 22 represents the origin admittance of the isolator output end, Y 12 represents the transfer admittance at the input end of the isolator, Y 21 represents the transfer admittance at the output end of the vibration isolator, v0 represents the free vibration velocity of the equipment, and Y′ R represents the actual installation base admittance; v′2 represents the vibration velocity of the installation point at the lower end of the isolator on the actual installation base.

[0077] In some embodiments, the excitation force at the lower end of the vibration isolator on the actual mounting base is calculated based on the free vibration speed, the machine foot admittance, the origin admittance of the vibration isolator input end, the origin admittance of the vibration isolator output end, the transfer admittance of the vibration isolator input end, the transfer admittance of the vibration isolator output end and the actual mounting base admittance, and the following formula is used for calculation:

[0078] K′=(Y S +Y 11 )Y 21 -1 (Y′ R +Y 22 )-Y 12 ;

[0079] F2′=-[K′] -1 v0;

[0080] Where K′ represents the transfer admittance matrix when the device is installed on the actual installation base, Y S Indicates the foot admittance of the equipment, Y 11 represents the origin admittance of the isolator input end, Y 22 represents the origin admittance of the isolator output end, Y 12 represents the transfer admittance at the input end of the isolator, Y 21 represents the transfer admittance at the output end of the vibration isolator, v0 represents the free vibration velocity of the equipment, and Y′ R represents the actual installation base admittance; F′2 represents the excitation force at the lower end of the isolator on the actual installation base.

[0081] The following is a specific example to further introduce the method for converting vibration parameters of equipment under different installation states in the present application.

[0082] Mechanical equipment is an important source of vibration and noise in engineering projects. Its vibration will have adverse effects on the surrounding environment, such as reducing system operation stability and personnel comfort. Therefore, many engineering projects have put forward control requirements for the vibration of mechanical equipment.

[0083] At present, the evaluation of mechanical equipment vibration is mainly carried out on the standard bench at the stage of equipment leaving the factory to obtain the vibration characteristics of the equipment. However, the vibration characteristics of mechanical equipment are closely related to its installation environment. Due to different boundary conditions in different installation environments, the vibration characteristics of mechanical equipment will also be different. Therefore, the factory vibration test results of mechanical equipment cannot directly reflect the vibration characteristics of the equipment after it is installed in the actual operating environment. Instead, it is necessary to convert the test results of the standard bench to the actual bench installation state through certain theoretical conversions to obtain the vibration state data after the equipment is installed in place, so as to timely discover vibration problems and eliminate hidden dangers.

[0084] The common mechanical equipment vibration isolation system consists of three parts: mechanical equipment, vibration isolation device and base. The mechanical equipment is used as a vibration source, and the excitation generated is transmitted to the vibration isolation device through the contact point between the mechanical equipment and the vibration isolation device, and then transmitted to the base structure through the contact point between the vibration isolation device and the base, causing the base structure to vibrate.

[0085] At present, there are few studies on the conversion methods of mechanical equipment excitation characteristics. Traditional methods often use the substructure method based on frequency response function to predict the vibration response of mechanical equipment vibration isolation system. The basic principle is to use the frequency response function of a single uncoupled component to form the total system response through impedance or admittance equations. However, due to the lack of modeling of mechanical equipment, it is difficult to predict the excitation characteristics of mechanical equipment under different installation environments.

[0086] In addition, there are usually multiple contact points between mechanical equipment, vibration isolators, and bases. In traditional modeling methods, the coupling between the contact points is generally ignored, which will lead to a decrease in high-frequency prediction accuracy.

[0087] The technical problem to be solved by this application;

[0088] The main technical problem solved by this intellectual achievement is to form a universal method for converting the excitation characteristics of mechanical equipment considering multi-point coupling, which can accurately predict the vibration characteristics of mechanical equipment in different installation environments, including:

[0089] (1) The traditional substructure method lacks modeling of mechanical equipment, resulting in incomplete modeling of the vibration isolation system, lack of versatility, and inability to predict the excitation characteristics of mechanical equipment under different installation environments. How to describe the excitation characteristics of mechanical equipment in the model and predict its changes in different installation environments is one of the key technical issues to be solved in this intellectual achievement.

[0090] (2) In the existing modeling of vibration isolation systems for mechanical equipment, the coupling effect between multiple installation points is ignored, resulting in a decrease in the accuracy of high-frequency prediction. This work considers the influence of multi-point coupling by testing the cross-point transfer function between multiple points in the model.

[0091] Technical points of this application:

[0092] (1) Conversion test conditions

[0093] 1) Point contact assumption. A typical mechanical equipment vibration isolation system consists of mechanical equipment, vibration isolators, and a base, such as Figure 3 As shown in the figure, the number of machine feet of the mechanical equipment is n, which are installed on the base through n vibration isolators. The maximum size of the contact area between the equipment, vibration isolators and base structure is much smaller than the vibration wavelength, so the joints (support points) between the vibration isolators and the equipment and base can be treated as point contacts below 1kHz.

[0094] 2) Before and after conversion, ensure that the equipment operating conditions are consistent so that the conversion is effective.

[0095] 3) This conversion method is applicable to elastically mounted or elastically suspended equipment.

[0096] 4) For equipment with pipelines, the inlet and outlet of the equipment generally have interference pipes, and the influence of the pipelines can be ignored; for pipelines that cannot be ignored, the pipelines can be considered as additional impedances and the impedance of the pipelines can be incorporated into the impedance of the vibration isolator.

[0097] (2) Conversion relationship between equipment excitation force and vibration velocity

[0098] 1) Equipment incentive model

[0099] According to the electromechanical analogy, the response speed v1 of the mechanical equipment foot is expressed as:

[0100] v1=v0-Y S F1; (1)

[0101] Where v1, v0 and F1 are n×1 vectors.

[0102] v1 is the device foot response speed:

[0103] v0 is the free vibration speed of the equipment feet:

[0104] F1 is the force exerted by the equipment feet on the vibration isolator:

[0105] Y S is the equipment foot admittance matrix, and its expression is as follows:

[0106] 2) Base response model

[0107] The base mounting point velocity is expressed as:

[0108] v2=-Y R F2; (2)

[0109] Among them, v2 and F2 are vectors, v2 is the response speed of the base, and F2 is the force exerted by the vibration isolator on the base.

[0110]

[0111] Among them, Y R is the base admittance matrix:

[0112]

[0113] 3) Isolator transfer model

[0114] Generally, the vibration isolators of the equipment are of the same model, and the speeds at the upper and lower ends of the vibration isolators can be expressed as:

[0115] v1=Y 11 F1+Y 12 F2; (3)

[0116] v2=Y 21 F1+Y 22 F2; (4)

[0117] where Y 11 , Y 12 , Y 21 and Y 22 is a diagonal matrix, Y 11 It is expressed as follows:

[0118]

[0119] Among them, Y1 i 1 represents the origin admittance of the input end of the ith isolator. For example: It is the origin admittance of the input end of the nth isolator.

[0120] Similarly, represents the origin admittance at the output end of the ith isolator; Represents the transfer admittance between the input and output ends of the i-th vibration isolator.

[0121] 4) Conversion relationship between excitation force and speed

[0122] The above formula can be used to deduce the relationship between the equipment foot response speed v1, the base response speed v2 and the equipment foot free vibration speed v0:

[0123] v1=[Y 11 Y 21 -1 (Y R +Y 22 )-Y 12 ]K -1 v0; (5)

[0124] v2=Y R K -1 v0; (6)

[0125] Where K = (Y S +Y 11 )Y 21 -1 (Y R +Y 22 )-Y 12 , which is equivalent to the transfer admittance matrix of the system.

[0126] According to formula (5), v0 can be calculated through the device foot response speed v1, and v0 can be used as a bridge for relationship conversion:

[0127] v0=K[Y 11 Y 21-1 (Y R +Y 22 )-Y 12 ] -1 v1; (7)

[0128] When the equipment is installed on other bases, the upper and lower end velocities and forces of the vibration isolator on the base can be calculated accordingly through the invariance of the free vibration velocity v0. The formula is as follows:

[0129]

[0130] Where K′=(Y S +Y 11 )Y 21 -1 (Y′ R +Y 22 )-Y 12 , Y′ R is the installation base admittance matrix. The superscripts represent the parameters on the new installation base, and the others are similar.

[0131] At this point, the conversion relationship between excitation force and speed in different installation environments of equipment that can be applied to actual engineering projects has been established.

[0132] The following is a detailed introduction to the conversion test and prediction method:

[0133] Conversion test and prediction method 1:

[0134] 1) Use ropes to suspend the mechanical equipment. When the mechanical equipment is in a free hanging state, place an acceleration sensor on each machine foot, and then use a hammer to hit each machine foot in turn to obtain the equipment foot admittance Y S .

[0135] 2) Arrange acceleration sensors at each installation point of the base of the mechanical equipment standard bench, and use a hammer to hit each base installation point in turn to obtain the bench base admittance Y R .

[0136] 3) Measure the impedance parameters of the vibration isolator and convert them to obtain the origin admittance Y of the vibration isolator 11 , Y 22 and transfer admittance Y 12 , Y 21 .

[0137] 4) Install the mechanical equipment on the base of the standard bench through a vibration isolator, turn on the equipment, and measure the machine foot speed v1 of the mechanical equipment.

[0138] 5) Arrange acceleration sensors at each installation point of the actual installation base of the mechanical equipment, and use a hammer to hit each installation point of the base in turn to obtain the actual installation base admittance Y′ R .

[0139] 6) Using the formula (7) of this patent, the free vibration speed v0 of the mechanical equipment is calculated using the machine foot speed v1 measured on the standard test bench.

[0140] 7) Using the formula (8) of this patent, the free vibration velocity v0 and the measured equipment foot admittance Y S , isolator admittance Y 11 , Y 22 , Y 12 , Y 21 , actual installation base admittance Y′ R The vibration velocity v′2, excitation force F′2 and other data of the base installation point under the actual installation environment are calculated.

[0141] Conversion test and prediction method 2:

[0142] 1) Use ropes to suspend the mechanical equipment. When the mechanical equipment is in a free hanging state, place an acceleration sensor on each machine foot, and then use a hammer to hit each machine foot in turn to obtain the equipment foot admittance Y S .

[0143] 2) Keep the mechanical equipment in a freely suspended state, turn on the equipment, and measure the free vibration velocity v0 of the mechanical equipment.

[0144] 3) Measure the impedance parameters of the vibration isolator and convert them to obtain the origin admittance Y of the vibration isolator 11 , Y 22 and transfer admittance Y 12 , Y 21 .

[0145] 4) Arrange acceleration sensors at each installation point of the actual installation base of the mechanical equipment, and use a hammer to hit each installation point of the base in turn to obtain the actual installation base admittance Y′ R .

[0146] 5) Using formula (8) of this application, with the measured free vibration velocity v0 and the measured equipment foot admittance Y S , isolator admittance Y 11 , Y 22 , Y 12 , Y 21 , actual installation base admittance Y′ R The vibration velocity v′2, excitation force F′2 and other data of the base installation point under the actual installation environment are calculated.

[0147] By adopting step 6) of the conversion test and prediction method 1, the calculated value of the equipment free vibration velocity v0 can be obtained; by adopting step 2) of the conversion test and prediction method 2, the calculated value of the equipment free vibration velocity v0 can be obtained. The comparison of v0 obtained by the two methods is shown in Table 1. It can be seen that the error of estimating the equipment free vibration velocity by the method of this application is only 0.5dB. And, as shown in the attached Figure 4 and attached Figure 5 As shown, the comparison results of the calculated value of the free vibration velocity v0 and the measured value show that the two values ​​are almost the same, which further demonstrates the accuracy of the calculated value of the equipment free vibration velocity v0 obtained by using step 6) of the prediction method 1 of this application.

[0148] Table 1 Comparison of the total level of free vibration speed of the machine foot (10~1kHz)

[0149]

[0150] Using method 1, step 7), the free vibration velocity v0 is used to calculate the excitation force on the upper and lower ends of the isolator when the device is installed on the actual base. The comparison with the measured data is shown in Table 2, Table 3 and Appendix. Figure 6 It can be seen that the error of estimating the excitation characteristics of the device in the actual installation environment by using the method of the present application is within 1.4dB.

[0151] Table 2 Comparison of total level of excitation force F′1 at the upper end of the vibration isolator (200Hz~1kHz)

[0152]

[0153] Table 3 Comparison of total level of excitation force F′2 at the lower end of the vibration isolator after conversion (200Hz~1kHz)

[0154]

[0155] 3. Beneficial effects.

[0156] (1) A complete vibration isolation system model of mechanical equipment was established. The free vibration velocity of the mechanical equipment was used to describe the characteristics of the equipment excitation source. The relationship between the free vibration velocity of the equipment and the vibration velocity and excitation force in the installed state was established. Compared with the traditional substructure model, it has better versatility and can realize the prediction of the excitation characteristics of mechanical equipment under different installation environments.

[0157] (2) Two testing and prediction methods for the conversion of mechanical equipment excitation characteristics considering multi-point coupling have been developed. On the basis of the traditional standard bench test, only the free suspension test of the mechanical equipment and the admittance test of the actual installation base are added to predict the vibration characteristics of the mechanical equipment in the actual installation environment. The operation is simple and the prediction effect is good.

[0158] In the embodiments of the present invention, the term "plurality" refers to two or more than two, unless otherwise clearly defined. The terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present invention can be understood according to the specific circumstances.

[0159] In addition, although each operation is described in a specific order, this should be understood as requiring such operation to be performed in a specific order or in a sequential order, or requiring that all illustrated operations should be performed to obtain desired results. Under certain circumstances, multitasking and parallel processing may be advantageous. Similarly, although some specific implementation details are included in the above discussion, these should not be interpreted as limiting the scope of the present invention. Some features described in the context of a separate embodiment can also be implemented in a single implementation in combination. On the contrary, the various features described in the context of a single implementation can also be implemented in multiple implementations individually or in any suitable sub-combination mode.

[0160] Although the subject matter has been described in the language of specific structural features and / or method logical actions, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or actions described above. On the contrary, the specific features and actions described above are merely example forms of implementing the claims.

[0161] The above are only preferred embodiments according to the embodiments of the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various modifications and changes may be made according to the embodiments of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the embodiments of the present invention shall be included in the protection scope of the embodiments of the present invention.

Claims

1. A method for converting vibration parameters of equipment under different installation conditions, characterized in that: include: The device is placed in a free hanging state, an acceleration sensor is arranged on each foot of the device, and each foot is hit in turn with an excitation hammer to obtain the admittance of the foot of the device; Obtaining the origin admittance of each vibration isolator input end, the origin admittance of the vibration isolator output end, the transfer admittance of the vibration isolator input end, and the transfer admittance of the vibration isolator output end; obtaining the free vibration velocity of the device; Arranging an acceleration sensor at each mounting point of the actual mounting base, and using an excitation hammer to sequentially strike each mounting point of the actual mounting base to obtain the admittance of the actual mounting base; The vibration parameters of the device installed on the actual installation base are calculated based on the free vibration velocity, the machine foot admittance, the origin admittance of the isolator input end, the origin admittance of the isolator output end, the transfer admittance of the isolator input end, the transfer admittance of the isolator output end and the actual installation base admittance.

2. The method for converting equipment vibration parameters under different installation states according to claim 1, characterized in that: The step of obtaining the free vibration velocity of the device comprises: Arrange an acceleration sensor at each mounting point of a standard base of a standard test bench, and use an excitation hammer to knock each mounting point of the standard base in turn to obtain the standard base admittance; Mounting the device on a standard base of the standard stand; Arrange a speed sensor on each machine foot of the device, turn on the device, and obtain the machine foot speed of the device on the standard stand; The free vibration speed of the equipment is calculated according to the standard base admittance, the machine foot speed, the origin admittance of the isolator input end, the origin admittance of the isolator output end, the transfer admittance of the isolator input end, the transfer admittance of the isolator output end and the machine foot admittance.

3. The method for converting equipment vibration parameters under different installation states according to claim 2, characterized in that: The free vibration speed of the equipment is calculated according to the standard base admittance, the machine foot speed, the origin admittance of the isolator input end, the origin admittance of the isolator output end, the transfer admittance of the isolator input end, the transfer admittance of the isolator output end and the machine foot admittance, using the following formula: K=(Y S +Y 11 )AND 21 -1 (AND R +Y 22 )-AND 12 ; v0=KY 11 Y 21 -1 (Y R +Y 22 )-Y 12 ] -1 v1; Wherein, v0 represents the free vibration velocity of the device, Y 11 represents the origin admittance of the isolator input end, Y 22 represents the origin admittance of the output end of the isolator, Y 12 represents the transfer admittance at the input end of the isolator, Y 21 represents the transfer admittance of the output end of the vibration isolator, v1 represents the foot speed of the equipment on the standard stand, and Y R represents the standard pedestal admittance, Y S represents the foot admittance of the device, and K represents the transfer admittance matrix when the device is installed on the standard base.

4. The method for converting equipment vibration parameters under different installation states according to claim 1, characterized in that: The step of obtaining the free vibration velocity of the device comprises: The device is placed in a free hanging state, and the device is turned on to directly measure the free vibration velocity of the device.

5. The method for converting equipment vibration parameters under different installation states according to claim 1, characterized in that: The step of obtaining the origin admittance of each vibration isolator input end, the origin admittance of the vibration isolator output end, the transfer admittance of the vibration isolator input end, and the transfer admittance of the vibration isolator output end comprises: measuring impedance parameters of the vibration isolator; The impedance parameter conversion is used to obtain the origin admittance of the isolator input end, the origin admittance of the isolator output end, the transfer admittance of the isolator input end and the transfer admittance of the isolator output end.

6. The method for converting equipment vibration parameters under different installation states according to any one of claims 1 to 5, characterized in that: The vibration parameters include at least one of the machine foot vibration velocity at the upper end of the vibration isolator on the actual mounting base, the excitation force at the upper end of the vibration isolator, the mounting point vibration velocity at the lower end of the vibration isolator, and the excitation force at the lower end of the vibration isolator.

7. The method for converting equipment vibration parameters under different installation states according to claim 6, characterized in that: The vibration velocity of the machine foot at the upper end of the vibration isolator on the actual mounting base is calculated according to the free vibration velocity, the machine foot admittance, the origin admittance of the isolator input end, the origin admittance of the isolator output end, the transfer admittance of the isolator input end, the transfer admittance of the isolator output end and the actual mounting base admittance, and the following formula is used for calculation: K′=(Y S +Y 11 )AND 21 -1 (AND' R +Y 22 )-AND 12 ; v′1=[Y 11 AND 21 -1 (AND' R +Y 22 )-AND 12 ][K′] -1 v0; Wherein, K′ represents the transfer admittance matrix when the device is installed on the actual installation base, Y S represents the foot admittance of the device, Y 11 represents the origin admittance of the isolator input end, Y 22 represents the origin admittance of the output end of the isolator, Y 12 represents the transfer admittance at the input end of the isolator, Y 21 represents the transfer admittance of the output end of the vibration isolator, v0 represents the free vibration velocity of the device, Y′ R represents the admittance of the actual mounting base; V′1 represents the vibration velocity of the machine foot at the upper end of the vibration isolator on the actual mounting base.

8. The method for converting equipment vibration parameters under different installation states according to claim 6, characterized in that: According to the free vibration speed, the machine foot admittance, the origin admittance of the isolator input end, the origin admittance of the isolator output end, the transfer admittance of the isolator input end, the transfer admittance of the isolator output end and the actual installation base admittance, the excitation force at the upper end of the isolator on the actual installation base is calculated using the following formula: K′=(Y S +Y 11 )AND 21 -1 (AND' R +Y 22 )-AND 12 ; F′1=Y 21 -1 (Y′ R +Y 22 )[K′] -1 v0; Wherein, K′ represents the transfer admittance matrix when the device is installed on the actual installation base, Y S represents the foot admittance of the device, Y 11 represents the origin admittance of the isolator input end, Y 22 represents the origin admittance of the output end of the isolator, Y 12 represents the transfer admittance at the input end of the isolator, Y 21 represents the transfer admittance of the output end of the vibration isolator, v0 represents the free vibration velocity of the device, Y′ R represents the admittance of the actual mounting base; F′1 represents the excitation force at the upper end of the vibration isolator on the actual mounting base.

9. The method for converting equipment vibration parameters under different installation states according to claim 6, characterized in that: According to the free vibration velocity, the machine foot admittance, the origin admittance of the isolator input end, the origin admittance of the isolator output end, the transfer admittance of the isolator input end, the transfer admittance of the isolator output end and the actual installation base admittance, the installation point vibration velocity of the lower end of the isolator on the actual installation base is calculated, and the following formula is used for calculation: K′=(Y S +Y 11 )AND 21 -1 (AND' R +Y 22 )-AND 12 ; v′2=Y′ R [K′] -1 v0; Wherein, K′ represents the transfer admittance matrix when the device is installed on the actual installation base, Y S represents the foot admittance of the device, Y 11 represents the origin admittance of the isolator input end, Y 22 represents the origin admittance of the output end of the isolator, Y 12 represents the transfer admittance at the input end of the isolator, Y 21 represents the transfer admittance of the output end of the vibration isolator, v0 represents the free vibration velocity of the device, Y′ R represents the admittance of the actual mounting base; v′2 represents the vibration velocity of the mounting point at the lower end of the isolator on the actual mounting base.

10. The method for converting equipment vibration parameters under different installation states according to claim 6, characterized in that: According to the free vibration speed, the machine foot admittance, the origin admittance of the isolator input end, the origin admittance of the isolator output end, the transfer admittance of the isolator input end, the transfer admittance of the isolator output end and the actual installation base admittance, the excitation force at the lower end of the isolator on the actual installation base is calculated by the following formula: K′=(Y S +Y 11 )AND 21 -1 (AND' R +Y 22 )-AND 12 ; F′2=-[K′] -1 v0; Wherein, K′ represents the transfer admittance matrix when the device is installed on the actual installation base, Y S represents the foot admittance of the device, Y 11 represents the origin admittance of the isolator input end, Y 22 represents the origin admittance of the output end of the isolator, Y 12 represents the transfer admittance at the input end of the isolator, Y 21 represents the transfer admittance of the output end of the vibration isolator, v0 represents the free vibration velocity of the device, Y′ R represents the admittance of the actual mounting base; F′2 represents the excitation force at the lower end of the isolator on the actual mounting base.

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