Torsional vibration envelope analysis method, device, equipment, medium and product

Abstract

The invention discloses a torsional vibration envelope analysis method, device and equipment, a medium and a product, and relates to the field of dynamic performance testing. The method comprises the following steps: constructing a torsional vibration dynamical model; determining a torsional vibration inherent frequency based on the torsional vibration dynamical model; determining a torsional vibration characteristic influence curve; based on the torsional vibration characteristic influence curve, according to the torsional vibration inherent frequency and the torsional excitation frequency, an isolation margin is determined through an enveloping principle; and determining the range of kinetic parameters of the test piece rotor system according to the isolation margin. According to the invention, whether the designed test piece can carry out an effective test bench performance test experiment or not can be ensured, and the method is of great significance in ensuring the safety of the test bench and preventing major safety production accidents.

Description

Technical Field

[0001] The present application relates to the field of dynamic performance testing, and in particular to a torsional vibration envelope analysis method, device, equipment, medium and product. Background Art

[0002] The rotor is the core component of rotating machinery and equipment, especially large rotating machinery. The rotor test bench and test piece are a complex rotor system with high power and high speed. They are also important experimental equipment for studying the dynamic characteristics, fault diagnosis, performance testing, etc. of the rotor. Rotor torsional vibration (abbreviated as torsional vibration) refers to the vibration phenomenon caused by the torsional torque generated by the rotor in the rotating machinery during operation. Rotor torsional vibration can cause fatigue damage and fracture of mechanical parts. Excessive vibration will cause stress concentration of parts, thereby reducing their life and safety of use. The dynamic envelope of the torsional vibration of the test piece on the test bench is of great significance. The result determines whether the designed test piece can carry out effective test bench performance test experiments. Therefore, the test bench rotor is required to have a certain torsional vibration envelope of the test piece.

[0003] At present, most of the research on the torsional vibration of the rotor test bench is about the detection and control of the torsional vibration of the rotor, and there is very little research on the torsional vibration envelope of the rotor test piece on the rotor test bench.

[0004] The conventional method for evaluating the dynamic envelope of the test bench rotor to the torsional vibration of the test piece rotor is to directly combine the test piece with the test bench rotor to obtain the dynamic performance indicators of the overall shaft system, and then evaluate whether the test piece can meet the dynamic requirements of the overall shaft system. If it cannot meet the requirements, the test piece needs to be redesigned for combined calculation. However, the process of this method of dynamic design of the test piece rotor is very cumbersome. Summary of the invention

[0005] The purpose of this application is to provide a torsional vibration envelope analysis method, device, equipment, medium and product, which can ensure whether the designed test piece can carry out effective test bench performance test experiments, which is of great significance to ensuring the safety of the test bench and preventing the occurrence of major production safety accidents.

[0006] To achieve the above objectives, this application provides the following solutions:

[0007] In a first aspect, the present application provides a torsional vibration envelope analysis method, which is applied to a shaft-rotor system; the shaft-rotor system comprises: a test bench rotor system and a test piece rotor system; the torsional vibration envelope analysis method comprises:

[0008] Constructing a torsional vibration dynamics model; the torsional vibration dynamics model is a physical simulation model constructed based on the elastic damping characteristics of the test bench rotor system to characterize the dynamic characteristics of the rotating machinery;

[0009] Determine the torsional vibration natural frequency based on the torsional vibration dynamics model; the torsional vibration natural frequency includes the torsional vibration natural frequencies of each order of the test bench rotor system;

[0010] Determine a torsional vibration characteristic influence curve; the torsional vibration characteristic influence curve is determined by applying different torsional vibration acceleration admittances at the interface, according to the variation trend of the torsional vibration natural frequency with the torsional vibration acceleration admittance; the interface is the connection between the test bench rotor system and the test piece rotor system;

[0011] Based on the torsional vibration characteristic influence curve, according to the torsional vibration natural frequency and the torsional excitation frequency, the isolation margin is determined by the envelope principle; the torsional excitation frequency includes: a constant frequency and a variable frequency; the constant frequency includes: an electrical circuit frequency and an electrical circuit frequency; the variable frequency includes: a variable frequency electric drive harmonic frequency and a synchronous motor asynchronous starting frequency;

[0012] The range of dynamic parameters of the rotor system of the test piece is determined according to the isolation margin; the dynamic parameters include: rotation frequency, motor end excitation frequency and synchronous excitation frequency.

[0013] Optionally, a transfer matrix method is used to determine the torsional vibration natural frequency according to the torsional vibration dynamics model.

[0014] Optionally, a transfer matrix method is used to determine the torsional vibration natural frequency according to the torsional vibration dynamics model, specifically including:

[0015] Using a transfer matrix method, determining the state variables of the torsional vibration dynamics model;

[0016] determining a transfer relationship according to the state variable;

[0017] Determine the torsional vibration frequency equation based on the boundary conditions at both ends and the transfer relationship;

[0018] The torsional vibration natural frequency is determined according to the torsional vibration frequency equation using a nonlinear least square method.

[0019] Optionally, the expression of the transfer relationship is:

[0020]

[0021] Where T is the section torque in the state variable; α is the section rotation angle in the state variable; K α is the torsional stiffness coefficient; J pis the lumped moment of inertia at the node; s is the complex frequency of torsional vibration; Γ is the transfer matrix between the two sections; i is the node number.

[0022] Optionally, the boundary conditions at both ends specifically include:

[0023] T1=T N+1 =0,α1≠0;

[0024] The expression of the torsional vibration frequency equation is:

[0025] U 12 =0;

[0026] Where T1 is the transfer matrix on the first section; T N+1 is the transfer matrix on the N+1th section; α1 is the rotation angle on the first section; U 12 is the torsional vibration frequency equation.

[0027] Optionally, determining the range of the dynamic parameters of the test piece rotor system according to the isolation margin specifically includes:

[0028] If the isolation margin is greater than the set threshold value, it is in a global envelope state, and the corresponding numerical range on the torsional vibration characteristic influence curve is determined as the initial range of the dynamic parameters;

[0029] If the isolation threshold is not greater than the set threshold, then determine whether the modal kinetic energy ratio is greater than the set ratio to obtain a determination result;

[0030] If the judgment result is yes, the excitation phenomenon occurs, and the corresponding value on the torsional vibration characteristic influence curve is determined as the maximum value of the initial range interval to obtain the adjustment range;

[0031] If the judgment result is no, the corresponding value on the torsional vibration characteristic influence curve is determined as the risk value; the risk value is a value that affects the dynamic performance of the shaft-rotor system;

[0032] The range of the kinetic parameter is determined according to the adjustment range and the risk value.

[0033] In a second aspect, the present application provides a torsional vibration envelope analysis device, comprising:

[0034] A model building module, used to build a torsional vibration dynamics model; the torsional vibration dynamics model is a physical simulation model built based on the elastic damping characteristics of the test bench rotor system to characterize the dynamic characteristics of the rotating machinery;

[0035] A torsional vibration natural frequency determination module, used to determine the torsional vibration natural frequency based on the torsional vibration dynamics model; the torsional vibration natural frequency includes the torsional vibration natural frequencies of each order of the test bench rotor system;

[0036] a torsional vibration characteristic influence curve determination module, used to determine the torsional vibration characteristic influence curve; the torsional vibration characteristic influence curve is determined by applying different torsional vibration acceleration admittances at the interface, according to the variation trend of the torsional vibration natural frequency with the torsional vibration acceleration admittance; the interface is the connection between the test bench rotor system and the test piece rotor system;

[0037] An isolation margin determination module is used to determine the isolation margin based on the torsional vibration characteristic influence curve, according to the torsional vibration natural frequency and the torsional excitation frequency, through the envelope principle; the torsional excitation frequency includes: a constant frequency and a variable frequency; the constant frequency includes: an electrical circuit frequency and an electrical circuit frequency; the variable frequency includes: a variable frequency electric drive harmonic frequency and a synchronous motor asynchronous starting frequency;

[0038] A determination module is used to determine the range of dynamic parameters of the test piece rotor system according to the isolation margin; the dynamic parameters include: rotation frequency, motor end excitation frequency and synchronous excitation frequency.

[0039] In a third aspect, the present application provides a computer device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the above-mentioned torsional vibration envelope analysis method.

[0040] In a fourth aspect, the present application provides a computer-readable storage medium having a computer program stored thereon, which implements the above-mentioned torsional vibration envelope analysis method when executed by a processor.

[0041] In a fifth aspect, the present application provides a computer program product, including a computer program, which implements the above-mentioned torsional vibration envelope analysis method when executed by a processor.

[0042] According to the specific embodiments provided in this application, this application discloses the following technical effects:

[0043] The present application provides a method, device, equipment, medium and product for torsional vibration envelope analysis. Through the torsional vibration envelope analysis of the test piece rotor by the test bench rotor, the dynamic parameter range of the test piece rotor that meets the torsional vibration index requirements of the test bench rotor is determined. When designing a new test piece, as long as its dynamic parameters are within this feasible range, the torsional vibration of the test bench rotor will not exceed the standard. Therefore, it is no longer necessary to repeatedly calculate the test bench rotor and the test piece rotor to evaluate whether the dynamic performance of the overall shaft system meets the standard. Therefore, the present application can ensure whether the designed test piece can carry out effective test bench performance test experiments, which is of great significance to ensuring the safety of the test bench and preventing the occurrence of major production safety accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 A flow chart of a torsional vibration envelope analysis method provided in an embodiment of the present application;

[0046] Figure 2 This is the overall shafting diagram of the compressor test bench;

[0047] Figure 3 It is the schematic diagram of the mechanical model for shaft torsional vibration analysis;

[0048] Figure 4 It is a schematic diagram of the interface between the compressor test bench rotor and the test piece rotor;

[0049] Figure 5 This is the torsional vibration envelope diagram of the compressor test bench rotor's various torsional vibration natural frequencies changing with the additional acceleration admittance of the interface;

[0050] Figure 6 This is the torsional vibration envelope diagram of the 1st to 4th order torsional vibration natural frequency of the compressor test bench rotor changing with the additional acceleration admittance of the interface;

[0051] Figure 7 A schematic diagram of the structure of a computer device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0052] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0053] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0054] This application divides the overall shaft system composed of the test bench rotor and the test piece rotor into two subsystems: the test bench rotor system and the test piece rotor system. The test piece rotor system is regarded as a "gray box", and its transverse vibration dynamic characteristics are described by its impedance or admittance characteristics at the interface between the two subsystems. The impedance matching principle (impedance synthesis method) is used to determine the mutual influence of the dynamic characteristics of the two subsystems, and further obtain the torsional vibration envelope diagram of the test bench rotor to the test piece rotor. The proposed torsional vibration envelope analysis method specifically refers to the torsional vibration modal envelope of the test bench rotor to the test piece rotor. According to the corresponding envelope diagram, the feasible range of the interface impedance characteristics of the test piece rotor can be clearly defined.

[0055] In summary, analyzing the envelope of the test bench's torsional vibration of the test piece is of great significance for reducing the wear of the test bench parts, ensuring the dynamic characteristics of the rotor, ensuring the safety of the test bench, and preventing major production safety accidents.

[0056] An embodiment of the present application provides a torsional vibration envelope analysis method, which is applied to a shaft-rotor system; the shaft-rotor system includes: a test bench rotor system and a test piece rotor system.

[0057] like Figure 1 As shown in Figure 2, the torsional vibration envelope analysis method includes:

[0058] Step 100: Construct a torsional vibration dynamics model. The torsional vibration dynamics model is a physical simulation model constructed based on the elastic damping characteristics of the test bench rotor system to characterize the dynamic characteristics of the rotating machinery.

[0059] Step 200: Determine the torsional vibration natural frequency based on the torsional vibration dynamics model. The torsional vibration natural frequency includes the torsional vibration natural frequencies of each order of the test bench rotor system.

[0060] Step 300: Determine the torsional vibration characteristic influence curve. The torsional vibration characteristic influence curve is determined by applying different torsional vibration acceleration admittances at the interface, according to the variation trend of the torsional vibration natural frequency with the torsional vibration acceleration admittance; the interface is the connection between the test bench rotor system and the test piece rotor system.

[0061] Step 400: Based on the torsional vibration characteristic influence curve, according to the torsional vibration natural frequency and the torsional excitation frequency, the isolation margin is determined by the envelope principle. The torsional excitation frequency includes: constant frequency and variable frequency; the constant frequency includes: electrical circuit frequency and electrical circuit frequency; the variable frequency includes: variable frequency electric drive harmonic frequency and synchronous motor asynchronous starting frequency.

[0062] Step 500: Determine the range of dynamic parameters of the test piece rotor system according to the isolation margin. The dynamic parameters include: rotation frequency, motor end excitation frequency and synchronous excitation frequency.

[0063] In one embodiment, a transfer matrix method is used to determine the torsional vibration natural frequency according to a torsional vibration dynamics model.

[0064] Among them, the transfer matrix method is used to determine the torsional vibration natural frequency according to the torsional vibration dynamics model, which specifically includes:

[0065] The transfer matrix method is used to determine the state variables of the torsional vibration dynamics model; the transfer relationship is determined based on the state variables; the torsional vibration frequency equation is determined based on the boundary conditions at both ends and the transfer relationship; the nonlinear least squares method is used to determine the torsional vibration natural frequency based on the torsional vibration frequency equation.

[0066] The expression of the transitive relation is:

[0067]

[0068] Where T is the section torque in the state variable; α is the section rotation angle in the state variable; K α is the torsional stiffness coefficient; J p is the lumped moment of inertia at the node; s is the complex frequency of torsional vibration; Γ i is the transfer matrix between the two sections, and its elements can be obtained by analyzing the forces and deformations on the components; i is the node number.

[0069] The boundary conditions at both ends include:

[0070] T1=T N+1 =0,α1≠0;

[0071] The expression of the torsional vibration frequency equation is:

[0072] U 12 =0;

[0073] Where T1 is the transfer matrix on the first section; T N+1 is the transfer matrix on the N+1th section; α1 is the rotation angle on the first section. 12 is the torsional vibration frequency equation.

[0074] In one embodiment, determining the range of the dynamic parameters of the test piece rotor system according to the isolation margin specifically includes:

[0075] If the isolation margin is greater than the set threshold value, it is in the global envelope state, and the corresponding numerical range on the torsional vibration characteristic influence curve is determined as the initial range of the dynamic parameters.

[0076] If the isolation threshold is not greater than the set threshold, it is determined whether the modal kinetic energy ratio is greater than the set ratio to obtain a judgment result; if the judgment result is yes, excitation occurs, and the corresponding value on the torsional vibration characteristic influence curve is determined as the maximum value of the initial range interval to obtain the adjustment range.

[0077] If the judgment result is no, the corresponding value on the torsional vibration characteristic influence curve is determined as the risk value; the risk value is a value that affects the dynamic performance of the shaft-rotor system.

[0078] Based on the adjustment range and risk value, the range of kinetic parameters is determined.

[0079] The solution in practical application is as follows:

[0080] 1. Establish the torsional vibration dynamics model of the test bench rotor system: including but not limited to the finite element method and transfer matrix method, to establish the torsional vibration dynamics model of the test bench rotor system.

[0081] 2. Define the interface: Determine the interface between the test bench rotor system and the test piece rotor system.

[0082] 3. Analyze the undamped torsional vibration natural frequency of the test bench rotor system: obtain the undamped torsional vibration natural frequency of the test bench rotor system at each stage.

[0083] 4. Analyze the influence of different torsional impedances on the torsional vibration characteristics of the test bench rotor: Apply different torsional vibration acceleration admittances at the interface, and analyze the changes of each order of torsional vibration natural frequency of the test bench rotor with torsional acceleration admittance.

[0084] 5. Analyze the torsional excitation frequency existing in the test bench: Usually the torsional excitation frequency of the test bench rotor includes constant (such as electrical line frequency and twice electrical line frequency) and variable (such as harmonics of variable frequency power drive or asynchronous starting of synchronous motor).

[0085] 6. Analyze the isolation margin between torsional excitation and torsional natural frequency: The isolation margin between the natural frequency of each order of torsional vibration of the shaft system that may be excited by the torque excitation of the shaft system and the corresponding excitation frequency should reach more than 10%;

[0086] 7. Analyze the proportion of modal kinetic energy: If the isolation margin is less than 10%, but in the torsional vibration mode corresponding to a component in the test bench subsystem, its modal kinetic energy accounts for less than 1%, it is considered that the mode will not be significantly excited by the excitation, and there is no need to have an avoidance rate requirement with the torsional vibration excitation frequency; if the modal kinetic energy accounts for more than 1%, it is considered that the mode will be excited and is not within the envelope range.

[0087] This application models the dynamic characteristics of the unknown test piece rotor as the mechanical impedance at the interface between the test bench rotor and the test piece rotor, and uses the impedance matching principle of the mechanical impedance synthesis method at the interface to determine the influence of the test piece rotor on the torsional vibration of the test bench rotor, thereby deriving the design limit range of the unknown test piece.

[0088] Taking a compressor rotor test bench as an example, the torsional vibration envelope of the test bench rotor on the test piece rotor is analyzed. The specific implementation steps are as follows:

[0089] A compressor is a component that uses high-speed rotating blades to compress and heat air to generate high-pressure gas. Its working process is: first, air is sucked in from the outside atmosphere, then the blades work to increase the air pressure, and finally the air is sent into the combustion chamber to mix with the fuel for combustion.

[0090] The compressor test bench overall shaft system consists of a synchronous motor shaft rotor, a low-speed gear sleeve coupling, a gearbox, a high-speed shaft rotor (including 3 sets of identical high-speed diaphragm couplings) and a test piece rotor, such as Figure 2 As shown. The rotor of the compressor test piece in the shaft system is radially supported by two sets of oil film bearings, and the rotor of the high-speed shaft is supported by two sets of rolling bearings. The output power of the synchronous motor is transmitted to the pinion on the high-speed shaft through the coupling and the speed increase gearbox, and then drives the rotor of the compressor test piece to rotate through the high-speed shaft. The design continuous operating speed range of the compressor test piece rotor is 3800rpm~10320rpm, that is, 63.3Hz~172Hz. The corresponding continuous rotation frequency of the motor shaft is 9.2Hz~25Hz. It is assumed that the stiffness of the support of each bearing in the test bench rotor system is much greater than the bearing stiffness, that is, the bearing seat is considered to be non-vibration-parallel, and each bearing is modeled as an elastic-damping element. The overall shaft system of the compressor test bench is supported by three pairs of bearings.

[0091] 1. Establish the torsional vibration dynamics model of the test bench rotor system.

[0092] The actual rotor is an elastic system with continuous mass distribution and infinite degrees of freedom. This application uses the Riccati transfer matrix method as an example but is not limited to the transfer matrix method to establish its torsional vibration motion equation. The transfer matrix method discretizes a continuous simple rotor system into a mechanical model with finite degrees of freedom. This model can reflect the dynamic characteristics of the original rotating machinery and is easy to analyze and calculate.

[0093] (1) Set nodes according to the shape and size of the shaft system. Generally, nodes are set at important locations such as bearing supports, before and after flexible couplings, impellers, and shaft ends. Figure 4 As shown in the blue hollow circle.

[0094] (2) The mass and moment of inertia of several subsystems are aggregated to several nodes, and the parameters are aggregated. After the parameters are aggregated, the rotor can be obtained into a disk-shaft dynamic model consisting of N rigid thin disks (nodes) with concentrated mass and moment of inertia, N massless elastic shaft segments, and N elastic damping supports. Figure 3 As shown, the rotor is discretized into a circular-axis unit consisting of n rigid thin disks and massless elastic shaft segments. The polar rotational inertia of the shaft segments is concentrated to the ends of the shaft segments according to the lumped parameter method.

[0095] The torsional displacement impedance of the test piece on the interface A is expressed as K αA Define the state variable as X = [Tα] T , then under the action of external torque excitation δT, the transfer relationship of the state variables at the left ends of two adjacent disks is:

[0096]

[0097] K α is the torsional stiffness coefficient; J p is the lumped moment of inertia at the node; s is the complex frequency of torsional vibration, K e and C e are the external torsional stiffness coefficient and viscous torsional damping coefficient on the node, j is the jth node, and δT is the external excitation. α =GI p / L (L is the length of the shaft segment, GI p For the coupling, the moment of inertia is also lumped to both ends of the coupling. The torsional stiffness coefficient K of the coupling is α Calculated by finite element model. Φ j is the transfer matrix.

[0098] When the system is not excited, the relationship between the state variables of the last disk and the first disk can be written as:

[0099] X n+1 =T n T n-1 ...T1X1=UX1

[0100] Using the boundary conditions at both ends T1 = T N+1 =0,α1≠0, the frequency equation of torsional vibration U 12 = 0, which is a 2n-order polynomial equation about the complex frequency s of torsional vibration. Solving it can obtain the natural frequencies of torsional vibrations of each order of the system. Among them, X n+1 is the state variable on the n+1th section, T n+1 is the transfer matrix on the n+1th section, and U is the expression of the torsional vibration frequency equation.

[0101] When there is an external simple harmonic excitation on the system disk, according to the first boundary condition T1 = 0, α1 is taken as the unknown quantity, and by iterating α1, the terminal boundary condition T n+1 =0, the torsional vibration stability response of the system can be obtained.

[0102] 2. Define the interface.

[0103] Since the structure and parameters of the test piece rotor system are unknown before the design is completed, the dynamic influence of the test piece rotor on the test bench rotor is realized through the mechanical impedance (dynamic stiffness) at the interface. Therefore, when analyzing the dynamic characteristics of the test bench rotor system, the torsional vibration characteristics of the test piece are characterized by its torsional mechanical impedance or admittance at the interface. The interface refers to the connection between the test bench subsystem and the test piece subsystem, such as Figure 4 shown.

[0104] 3. Analyze the undamped torsional natural frequency of the test bench subsystem

[0105] The undamped torsional vibration analysis process is to determine the undamped torsional natural frequencies and mode shapes of the shafting based on the torsional vibration dynamics model established in step 1. The purpose is to plot these together with all relevant excitation sources in the system on a Campbell diagram to determine in step 6 whether there are any crossover points within the operating speed range of the shafting or what the separation margin of the relevant excitation frequencies is.

[0106] The undamped torsional natural frequency of the test bench rotor is solved by the transfer matrix method, but is not limited to this method:

[0107] Since the torsional vibration analysis mechanical model has no support, the stiffness and damping of the support part do not exist and are directly recorded as 0 in the transfer matrix. At the same time, consider the state variable X = [Tα] T , we can get the transfer relationship of the state variables at the left ends of two adjacent disks as follows:

[0108]

[0109] in

[0110]

[0111] According to the idea of ​​transfer matrix method, the relationship between the state variables of the last disk and the state variables of the first disk is:

[0112] X n+1 =Γ n Γ n-1 ...Γ1X1=UX1

[0113] Using the boundary conditions at both ends T1 = T N+1 =0,α1≠0, the frequency equation of torsional vibration U12 =0, which is a 2n-order polynomial equation about the torsional vibration complex frequency s. The nonlinear least squares method can be used to solve it to obtain the natural frequencies of each order of torsional vibration of the system.

[0114] 4. Analyze the influence of different torsional impedance (acceleration admittance) on the torsional vibration characteristics of the test bench rotor.

[0115] (1) Apply different torsional vibration acceleration admittances on the interface nodes, and analyze the changes of the natural frequencies of each order of torsional vibration of the test bench rotor with torsional acceleration admittance. The torsional vibration acceleration impedance (also called "apparent moment of inertia") of the test piece rotor on the interface is defined as J eA =-K αA / ω 2 , where ω is the rotor torsional vibration circular frequency, K αA is the torsional displacement impedance of the test piece on the interface A, J eA The reciprocal of is the torsional acceleration admittance.

[0116] (2) According to step 3, solve the change of each order torsional vibration natural frequency of the test bench subsystem with the additional admittance of the interface.

[0117] Table 1 gives the additional acceleration admittance 1 / J of several interfaces. eA Under the condition of the compressor test bench subsystem, the change of the torsional vibration natural frequency below 1200Hz (the maximum rotation frequency of the 48X motor) is shown.

[0118] Table 1 Changes of natural frequencies of various torsional vibrations of compressor test bench subsystem with additional acceleration admittance of interface

[0119]

[0120] Tables 2 and 3 show the changes in the modal kinetic energy ratio RVM of the motor shaft and the modal kinetic energy ratio RVT of the test piece for each torsional vibration mode of the test bench subsystem under different additional acceleration admittances.

[0121] Table 2 Changes in the modal kinetic energy ratio RVM of the motor shaft and the modal kinetic energy ratio RVT of the test piece in each torsional vibration mode of the compressor test bench

[0122]

[0123]

[0124] Table 3 Changes in the modal kinetic energy ratio RVM of the motor shaft and the modal kinetic energy ratio RVT of the test piece in each torsional vibration mode of the compressor test bench

[0125]

[0126] 5. Analyze the torsional excitation frequency present in the test bench.

[0127] Analyze the torsional excitation frequency of the test bench rotor and find out the significant frequency components.

[0128] (1) Analyze the electrical excitation frequency. In this application, the electromagnetic torque of the synchronous drive motor of the compressor test bench contains a large number of frequency components. According to the design data, the dynamic electromagnetic torque components of 1×fm, 6×fm, 12×fm and 24×fm (fm is the motor rotation frequency) are relatively significant, and the torque components of other frequency components are very small. Therefore, when performing envelope analysis in this case, the torque excitation of the motor only considers these more significant frequency components.

[0129] (2) Analyze the excitation frequency on the test piece. There may also be dynamic torque excitation of gas on the test piece, and its frequency is a multiple of the rotation frequency of the test piece. Generally, only the torque excitation of 1 multiple is significant, and the torque excitation force amplitude of other multiples is very small. Therefore, only the torque excitation of 1 multiple on the test piece is considered in this application. In addition, there is no obvious dynamic torque excitation on other parts of the compressor test bench shaft system, so it is not considered.

[0130] 6. Analyze the isolation margin between torsional excitation and torsional natural frequency.

[0131] Figure 5 The additional torsional acceleration admittance 1 / J on the interface is given eA When the test bench subsystem changes, the natural frequencies of each mode change. According to the principle of envelope, if the isolation margin between the natural frequencies of each order of torsional vibration of the shaft system that may be excited by the torque excitation of the shaft system and the corresponding excitation frequency reaches more than 10%, the whole domain can be enveloped, and no modal kinetic energy proportion analysis is required.

[0132] exist Figure 4 The middle dotted line is the torsional vibration acceleration admittance curve of the existing test piece subsystem on the interface, and its intersection with the natural frequency line of the test bench subsystem is the torsional vibration natural frequency of the overall system. From md1 to md5, the realizations of different colors represent the changes of the natural frequencies under different torsional vibration modes with the torsional vibration acceleration admittance of the test piece interface. The test bench design has a continuous rotation frequency range of 63.3Hz to 172Hz, corresponding to a motor rotation frequency of 9.2Hz to 25Hz. It can be seen from the figure that modes 5 to 8 are risk-free for all possible test piece designs, that is, they can be fully enveloped.

[0133] 7. Analyze the proportion of modal kinetic energy.

[0134] If the isolation margin is less than 10%, and the proportion of modal kinetic energy in the torsional vibration mode corresponding to a component in the test bench subsystem is less than 1%, it is considered that the mode will not be significantly excited by the excitation and does not need to meet the avoidance rate requirement; if the proportion of modal kinetic energy is greater than 1%, it is considered that the modal kinetic energy will be excited by the excitation and is not within the envelope range.

[0135] According to the calculation results of step 4 and Figure 5 It can be seen that the motor end modal kinetic energy ratio RVM of mode 5 to mode 8 is less than 0.1%, and there is no risk on the motor end. In addition, the natural frequencies of these modes are all higher than 189Hz, and there is no risk on the test piece end, that is, these modes will not be excited by the torsional excitation that may exist in the system or the avoidance rate of their natural frequencies and possible test continuous rotation frequencies exceeds 10%. Modes 1 to 4 are risky for specific test frequencies or for test pieces with specific interface acceleration admittance characteristics, so Modes 1 to 4 are analyzed in detail.

[0136] from Figure 6 It can be concluded that as 1 / J eA The frequency variation range of mode 1 is 0~42.8Hz, and its highest frequency is less than 0.9 times of the minimum continuous rotation frequency ft_min of the test piece (i.e. 57Hz), and also less than 0.9 times of the minimum rotation frequency 6*fm_min of the 6X motor (i.e. 49.7Hz). Therefore, mode 1 has no risk to the synchronous torsional excitation frequency ft on the test piece and the motor end excitation frequency of 6*fm and above. However, under a certain 1 / J eA Within the range, the frequency of mode 1 does not have enough avoidance rate with the rotation frequency fm of the motor, that is, mode 1 is risky for synchronous torsional excitation at the motor end. If the full-domain envelope test piece is required to design a rotation frequency range of 63.3Hz to 172Hz, then the acceleration admittance characteristic of mode 1 on the test piece at the interface is 1 / J eA There are certain restrictions, namely 1 / J eA >0.135kg -1 ·m -2 or 1 / J eA <0.0033kg -1 ·m -2 .

[0137] With 1 / J eA The frequency range of mode 2 is 42.8Hz~94.9Hz. eA <0.394kg -1 ·m -2The frequency of mode 2 is less than 0.9×ft_min (i.e. 57Hz), and mode 2 poses no risk to the test piece. The frequency of mode 2 is also significantly higher than 1.1×fm_max (i.e. 27.5Hz), and poses no risk to the synchronous excitation frequency at the motor end, but at a specific 1 / J eA The frequency of mode 2 in the range does not have enough avoidance rate with the excitation frequency of 6×fm, but when the frequency of mode 2 is greater than 70.4Hz, the modal kinetic energy ratio RVM at the motor end will be less than 1%. Therefore, when the motor rotation frequency is greater than 13Hz, mode 2 poses no risk to the motor end. When 1 / J eA <0.123kg -1 ·m -2 When the frequency of mode 2 is less than 0.9 times of 6*fm_min (ie 49.7Hz), mode 2 has no restriction on the test frequency of the continuous rotation frequency range of 63.3Hz to 172Hz, that is, it covers the entire range of rotation frequencies.

[0138] With 1 / J eA The frequency variation range of mode 3 is 94.9Hz~183Hz. The proportion of torsional vibration energy at the motor end of mode 3 is less than 1% in the natural frequency range of 94.9Hz~182Hz. When the excitation frequency at the motor end is less than 165Hz, there is no risk at the motor end. The frequency of mode 3 does not have enough avoidance rate with the possible continuous rotation frequency of the test piece, so there is a risk at the test piece end.

[0139] With 1 / J eA The frequency variation range of mode 4 is 183Hz~194Hz. The torsional vibration energy of the motor end of mode 4 accounts for more than 1% of the natural frequency interval, and there is a risk on the motor end. To eliminate the risk on the motor end, the excitation frequency of the motor end must be less than 166Hz; the torsional vibration energy of the test piece of this mode accounts for more than 1% in some natural frequency intervals, and there is a risk on the test piece end. To eliminate the risk on the test piece end, the synchronous excitation frequency of the test piece must be less than 165Hz. If it is required that this mode is risk-free to the test piece end within the full speed range of 3800rpm~10320rpm, then 1 / J is required. eA >41kg -1 ·m -2 .

[0140] Based on the same inventive concept, the embodiment of the present application also provides a torsional vibration envelope analysis device for implementing the torsional vibration envelope analysis method involved above. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme recorded in the above method, so the specific limitations in one or more torsional vibration envelope analysis device embodiments provided below can refer to the limitations of the torsional vibration envelope analysis method above, and will not be repeated here.

[0141] In an exemplary embodiment, a torsional vibration envelope analysis device is provided, comprising:

[0142] The model building module is used to build a torsional vibration dynamics model; the torsional vibration dynamics model is a physical simulation model built based on the elastic damping characteristics of the test bench rotor system to characterize the dynamic characteristics of the rotating machinery.

[0143] The torsional vibration natural frequency determination module is used to determine the torsional vibration natural frequency based on the torsional vibration dynamics model; the torsional vibration natural frequency includes the torsional vibration natural frequencies of each order of the test bench rotor system.

[0144] The torsional vibration characteristic influence curve determination module is used to determine the torsional vibration characteristic influence curve; the torsional vibration characteristic influence curve is determined by applying different torsional vibration acceleration admittances at the interface, according to the variation trend of the torsional vibration natural frequency with the torsional vibration acceleration admittance; the interface is the connection between the test bench rotor system and the test piece rotor system.

[0145] The isolation margin determination module is used to determine the isolation margin based on the torsional vibration characteristic influence curve, according to the torsional vibration natural frequency and the torsional excitation frequency, through the envelope principle; the torsional excitation frequency includes: constant frequency and variable frequency; the constant frequency includes: electrical line frequency and electrical line frequency; the variable frequency includes: variable frequency power drive harmonic frequency and synchronous motor asynchronous starting frequency.

[0146] The determination module is used to determine the range of dynamic parameters of the test piece rotor system according to the isolation margin; the dynamic parameters include: rotation frequency, motor end excitation frequency and synchronous excitation frequency.

[0147] In an exemplary embodiment, a computer device is provided. The computer device may be a server or a terminal. The internal structure diagram thereof may be as follows: Figure 7 As shown. The computer device includes a processor, a memory, an input / output interface (Input / Output, referred to as I / O) and a communication interface. The processor, the memory and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a torsional vibration envelope analysis method is implemented.

[0148] Those skilled in the art will understand that Figure 7 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0149] In an exemplary embodiment, a computer device is further provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps in the above-mentioned method embodiments when executing the computer program.

[0150] In an exemplary embodiment, a computer-readable storage medium is provided, storing a computer program, and when the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0151] In an exemplary embodiment, a computer program product is provided, including a computer program, and when the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0152] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0153] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM may be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0154] The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. The non-relational database may include a distributed database based on blockchain, etc., but is not limited thereto. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but is not limited thereto.

[0155] The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0156] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A method for analyzing torsional vibration envelope, characterized in that: The torsional vibration envelope analysis method is applied to the shaft-rotor system; The shaft system rotor system includes: a test bench rotor system and a test piece rotor system; the torsional vibration envelope analysis method includes: Constructing a torsional vibration dynamics model; the torsional vibration dynamics model is a physical simulation model constructed based on the elastic damping characteristics of the test bench rotor system to characterize the dynamic characteristics of the rotating machinery; Determine the torsional vibration natural frequency based on the torsional vibration dynamics model; the torsional vibration natural frequency includes the torsional vibration natural frequencies of each order of the test bench rotor system; Determine a torsional vibration characteristic influence curve; the torsional vibration characteristic influence curve is determined by applying different torsional vibration acceleration admittances at the interface, according to the variation trend of the torsional vibration natural frequency with the torsional vibration acceleration admittance; the interface is the connection between the test bench rotor system and the test piece rotor system; Based on the torsional vibration characteristic influence curve, according to the torsional vibration natural frequency and the torsional excitation frequency, the isolation margin is determined by the envelope principle; the torsional excitation frequency includes: a constant frequency and a variable frequency; the constant frequency includes: an electrical circuit frequency and an electrical circuit frequency; the variable frequency includes: a variable frequency electric drive harmonic frequency and a synchronous motor asynchronous starting frequency; The range of dynamic parameters of the rotor system of the test piece is determined according to the isolation margin; the dynamic parameters include: rotation frequency, motor end excitation frequency and synchronous excitation frequency.

2. The torsional vibration envelope analysis method according to claim 1, characterized in that: The torsional vibration natural frequency is determined according to the torsional vibration dynamics model by using a transfer matrix method.

3. The torsional vibration envelope analysis method according to claim 2, characterized in that: The transfer matrix method is used to determine the torsional vibration natural frequency according to the torsional vibration dynamics model, specifically including: Using a transfer matrix method, determining the state variables of the torsional vibration dynamics model; determining a transfer relationship according to the state variable; Determine the torsional vibration frequency equation based on the boundary conditions at both ends and the transfer relationship; The torsional vibration natural frequency is determined according to the torsional vibration frequency equation using a nonlinear least square method.

4. The torsional vibration envelope analysis method according to claim 3, characterized in that: The expression of the transfer relationship is: Where T is the section torque in the state variable; α is the section rotation angle in the state variable; K α is the torsional stiffness coefficient; J p is the lumped moment of inertia at the node; s is the complex frequency of torsional vibration; Γ i is the transfer matrix between two sections; i is the node number.

5. The torsional vibration envelope analysis method according to claim 3, characterized in that: The boundary conditions at both ends specifically include: T1=T N+1 =0,α1≠0; The torsional vibration frequency equation is expressed as: U 12 ＝0； Where T1 is the transfer matrix on the first section; T N+1 is the transfer matrix on the N+1th section; α1 is the rotation angle on the first section; U 12 is the torsional vibration frequency equation.

6. The torsional vibration envelope analysis method according to claim 1, characterized in that: Determining the range of dynamic parameters of the test piece rotor system according to the isolation margin specifically includes: If the isolation margin is greater than the set threshold value, it is in a global envelope state, and the corresponding numerical range on the torsional vibration characteristic influence curve is determined as the initial range of the dynamic parameters; If the isolation threshold is not greater than the set threshold, then determine whether the modal kinetic energy ratio is greater than the set ratio to obtain a determination result; If the judgment result is yes, the excitation phenomenon occurs, and the corresponding value on the torsional vibration characteristic influence curve is determined as the maximum value of the initial range interval to obtain the adjustment range; If the judgment result is no, the corresponding value on the torsional vibration characteristic influence curve is determined as the risk value; the risk value is a value that affects the dynamic performance of the shaft-rotor system; The range of the kinetic parameter is determined according to the adjustment range and the risk value.

7. A torsional vibration envelope analysis device, characterized in that: The torsional vibration envelope analysis device comprises: A model building module, used to build a torsional vibration dynamics model; the torsional vibration dynamics model is a physical simulation model built based on the elastic damping characteristics of the test bench rotor system to characterize the dynamic characteristics of the rotating machinery; A torsional vibration natural frequency determination module, used to determine the torsional vibration natural frequency based on the torsional vibration dynamics model; the torsional vibration natural frequency includes the torsional vibration natural frequencies of each order of the test bench rotor system; a torsional vibration characteristic influence curve determination module, used to determine the torsional vibration characteristic influence curve; the torsional vibration characteristic influence curve is determined by applying different torsional vibration acceleration admittances at the interface, according to the variation trend of the torsional vibration natural frequency with the torsional vibration acceleration admittance; the interface is the connection between the test bench rotor system and the test piece rotor system; An isolation margin determination module is used to determine the isolation margin based on the torsional vibration characteristic influence curve, according to the torsional vibration natural frequency and the torsional excitation frequency, through the envelope principle; the torsional excitation frequency includes: a constant frequency and a variable frequency; the constant frequency includes: an electrical circuit frequency and an electrical circuit frequency; the variable frequency includes: a variable frequency electric drive harmonic frequency and a synchronous motor asynchronous starting frequency; The determination module is used to determine the range of dynamic parameters of the test piece rotor system according to the isolation margin; the dynamic parameters include: rotation frequency, motor end excitation frequency and synchronous excitation frequency.

8. A computer device comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the torsional vibration envelope analysis method according to any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the torsional vibration envelope analysis method described in any one of claims 1 to 6 is implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the torsional vibration envelope analysis method described in any one of claims 1 to 6 is implemented.

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