Turboshaft engine external piping vibration assessment method, system, equipment and medium

Abstract

The present invention discloses a method and system, equipment, and medium for evaluating the vibration of the external piping of a turboshaft engine. The method first performs finite element calculation and analysis on the external piping, and corrects the connection stiffness through a knocking frequency test. The influence of the connection stiffness is considered, and the finite element calculation model is corrected so that the calculated resonance frequency is consistent with the knocking resonance frequency, thereby obtaining accurate pipeline vibration characteristics, which is beneficial to improving the accuracy of pipeline risk assessment, and only requires simple test comparison frequency results to verify and correct the finite element calculation model, without the need for complex modal tests. Then, by combining finite element calculation with the maximum unbalance test of the whole machine, based on accurate finite element calculation results combined with the installation of the whole machine, the vibration of the external piping can be simulated more accurately, which is beneficial to further improving the accuracy of pipeline risk assessment.

Description

Technical Field

[0001] The present invention relates to the technical field of pipeline vibration assessment, and in particular, to a turboshaft engine external pipeline vibration assessment method and system, electronic equipment, and a computer-readable storage medium. Background Art

[0002] The pipeline is called the "meridian" of the turboshaft engine. It is mainly divided into fuel pipes, lubricating oil pipes, air pipes, etc., which have the functions of providing fuel delivery, lubricating oil inlet / outlet, air bleed, and leakage removal for the turboshaft engine. Figure 1 As shown in the figure, common external pipelines are generally composed of pipe bodies and adapters welded together, and the two ends are connected to the casing through adapters and outer sleeve nuts respectively. A clamp is often connected in the middle section for enhanced fixation. It is subjected to vibration stress during the operation of the engine. However, due to the relatively weak points such as welds, adapters, and processing defects, cracks are prone to occur. In severe cases, it will lead to oil leakage / gas leakage and other consequences that endanger the safety of the engine. Therefore, it is necessary to conduct vibration risk assessment on external pipelines. Existing vibration assessment methods include finite element calculation method and vibration table component test method. Among them, the finite element calculation method is to judge whether the pipeline has resonance risk by comparing the margin between the calculated natural frequency of the pipeline and the excitation frequency of the engine rotor, while the vibration table component test method is to directly connect the pipeline to the adapter section, and then fix it on the table of the vibration table, and evaluate the vibration risk of the pipeline through strain / stress testing.

[0003] However, the boundary conditions of the existing finite element calculation method are usually designed as fixed connection, without considering the connection stiffness between the adapter and the casing, the connection stiffness between the outer nut and the casing, and the connection stiffness between the clamp and the casing. It is impossible to accurately calculate the pipeline vibration characteristics, resulting in poor accuracy of the vibration risk assessment results. In addition, there are large differences between the vibration table component test and the actual installation of the whole machine. Specifically, Figure 2 As shown, the aircraft engine can be understood as a simple cylinder. The pipeline is installed on the cylindrical surface. The two ends of the pipeline are connected to the cylindrical surface through joints. Some of the longer pipelines have clamps in the middle, one end of the pipeline is clamped and the other end is also connected to the cylindrical surface, that is, the joints and clamps at both ends of the pipeline (i.e. Figure 2 The block in the figure is installed on the cylindrical surface. The vibration of the engine is caused by the rotation of the rotor inside. Therefore, its external vibration is from the center of the circle to the surrounding area, that is, radial. Therefore, the vibration of the external pipeline is also radial vibration. The vibration direction of the vibration table is unidirectional, either vertically or horizontally. Figure 3As shown, the external pipeline is subjected to unidirectional vibration, which is inconsistent with the actual vibration direction installed on the engine. In addition, since the pipeline adapter cannot be directly installed on the vibration table, it needs to be installed on the vibration table through a complex and bulky adapter section. It is also impossible to accurately obtain the pipeline vibration characteristics, resulting in poor accuracy of the vibration risk assessment results. In addition, the existing vibration assessment methods do not consider the vibration risks of weak locations such as welds, which greatly reduces the reliability of pipeline design. In summary, the existing vibration assessment methods are relatively rough and cannot accurately identify vibration risks. There are problems such as inadequate consideration and insufficient component test verification. Summary of the invention

[0004] The present invention provides a method and system for evaluating the vibration of an external pipeline of a turboshaft engine, electronic equipment, and a computer-readable storage medium, which can improve the accuracy of risk evaluation of the external pipeline.

[0005] According to one aspect of the present invention, a method for evaluating vibration of an external piping of a turboshaft engine is provided, comprising the following contents:

[0006] Finite element analysis was performed on the external piping of the turboshaft engine, and the connection stiffness was corrected through a knocking frequency test so that the calculated resonance frequency was consistent with the knocking resonance frequency, and the resonance frequency, vibration mode and vibration stress distribution of the external piping were obtained;

[0007] Based on the vibration mode and vibration stress distribution of the external pipeline, after pasting the strain gauge at the point with maximum vibration stress in the direction of vibration stress, the maximum unbalance test of the whole machine is carried out, and the pipeline vibration risk is evaluated according to the test results.

[0008] Furthermore, the process of correcting the connection stiffness by the knocking frequency test includes the following contents:

[0009] The knocking resonance frequency is obtained by knocking on the external pipe entity in the installed state, and then the connection stiffness between the adapter and the casing, the connection stiffness between the outer sleeve nut and the casing, and the connection stiffness between the clamp and the casing are changed during the finite element calculation, so that the calculated resonance frequency is consistent with the knocking resonance frequency, thereby correcting the finite element calculation model.

[0010] Furthermore, if the strain gauge cannot be pasted at the location where the vibration stress is maximum, the strain gauge is pasted in the adjacent area where the vibration stress is maximum, and the vibration stress value at the location where the vibration stress is maximum is calculated by proportional conversion based on the vibration stress value and vibration stress distribution measured in the adjacent area.

[0011] Furthermore, the following contents are also included:

[0012] For external pipelines and weak locations where strain gauges cannot be attached, pipeline fatigue test pieces with the same vibration shape, vibration stress distribution, resonance frequency and installation structure as the original pipeline are designed according to the resonance frequency, vibration shape and vibration stress distribution of the external pipeline, and a resonance residence test is carried out.

[0013] Furthermore, the pipeline fatigue test piece adopts a straight tube structure with one end fixed and the other end suspended, and the vibration mode, vibration stress distribution and resonance frequency of the test piece are adjusted by changing the length of the straight tube.

[0014] Furthermore, the resonance dwell time threshold is calculated based on the following formula:

[0015]

[0016] Wherein, T represents the resonance dwell time, ω represents the dwell frequency, and if the resonance dwell time exceeds the time threshold and the test piece does not produce crack damage, it is determined that the high cycle fatigue life requirement is met.

[0017] In addition, the present invention also provides a turboshaft engine external piping vibration assessment system, comprising:

[0018] Finite element calculation and correction module, used to carry out finite element calculation and analysis on the external piping of the turboshaft engine, and correct the connection stiffness through knocking frequency test, so that the calculated resonance frequency is consistent with the knocking resonance frequency, and the resonance frequency, vibration mode and vibration stress distribution of the external piping are obtained;

[0019] The pipeline vibration risk assessment module is used to conduct a maximum unbalance test of the whole machine based on the vibration mode and vibration stress distribution of the external pipeline, after pasting the strain gauge in the direction of the vibration stress at the point with the maximum vibration stress, and evaluate the pipeline vibration risk according to the test results.

[0020] Furthermore, it also includes:

[0021] The high-cycle fatigue life assessment module is used for external pipelines and weak locations where strain gauges cannot be attached. According to the resonance frequency, vibration mode and vibration stress distribution of the external pipeline, the pipeline fatigue test piece with the same vibration mode, vibration stress distribution, resonance frequency and installation structure as the original pipeline is designed, and a resonance residence test is performed.

[0022] In addition, the present invention also provides an electronic device, including a processor and a memory, wherein the memory stores a computer program, and the processor executes the steps of the above method by calling the computer program stored in the memory.

[0023] In addition, the present invention also provides a computer-readable storage medium for storing a computer program for performing vibration evaluation on an external piping of a turboshaft engine, wherein the computer program executes the steps of the method described above when running on a computer.

[0024] The present invention has the following beneficial effects:

[0025] The method for evaluating the vibration of the external pipeline of a turboshaft engine of the present invention first carries out finite element calculation and analysis on the external pipeline, and corrects the connection stiffness through a knocking frequency test, taking into account the influence of the connection stiffness, corrects the finite element calculation model, makes the calculated resonance frequency consistent with the knocking resonance frequency, and obtains the finite element calculation results verified by the experiment, so that accurate pipeline vibration characteristics can be obtained, which is beneficial to improving the accuracy of pipeline risk assessment, and only requires simple test comparison frequency results to verify and correct the finite element calculation model, without the need for complex modal tests. Then, based on the vibration mode and vibration stress distribution calculated by the corrected finite element model, after the strain gauge is pasted in the direction of the vibration stress at the maximum vibration stress, the maximum unbalance test of the whole machine is carried out, and the pipeline vibration risk is evaluated according to the test results. By adopting a combination of finite element calculation and the maximum unbalance test of the whole machine, based on accurate finite element calculation results combined with the installation of the whole machine, the vibration of the external pipeline can be simulated more accurately, which is beneficial to further improve the accuracy of pipeline risk assessment.

[0026] In addition, the turboshaft engine external piping vibration assessment system of the present invention also has the above advantages.

[0027] In addition to the above-described purposes, features and advantages, the present invention has other purposes, features and advantages. The present invention will be further described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0029] Figure 1 This is a schematic diagram of the common external piping structure;

[0030] Figure 2 It is a simplified schematic diagram of the external piping installed on an aircraft engine;

[0031] Figure 3 It is a simplified schematic diagram of the external piping installed on the vibration table;

[0032] Figure 4 It is a flow chart of a method for evaluating vibration of an external pipeline of a turboshaft engine according to a preferred embodiment of the present application;

[0033] Figure 5 It is a schematic diagram of the pipeline vibration mode at the first-order resonance frequency obtained by performing pipeline finite element calculation and analysis in the preferred embodiment of the present application;

[0034] Figure 6 It is a schematic diagram of pipeline vibration stress distribution at the first-order resonance frequency obtained by performing pipeline finite element calculation and analysis in the preferred embodiment of the present application;

[0035] Figure 7 It is a schematic diagram of the principle of performing finite element calculation of pipelines in the preferred embodiment of the present application;

[0036] Figure 8 It is another schematic flow chart of the method for evaluating the vibration of the external piping of a turboshaft engine according to a preferred embodiment of the present application;

[0037] Fig. 9 is a schematic diagram of a pipeline weld in a preferred embodiment of the present application;

[0038] Fig.10 It is a schematic diagram of the weld end vibration mode of the original pipeline in the preferred embodiment of the present application;

[0039] Fig.11 It is a schematic diagram of the weld end vibration mode of the pipeline fatigue test piece designed in the preferred embodiment of the present application;

[0040] Fig.12 It is a schematic diagram of the vibration stress distribution at the original pipeline weld in the preferred embodiment of the present application;

[0041] Fig.13 It is a schematic diagram of the vibration stress distribution at the weld of the pipeline fatigue test piece designed in the preferred embodiment of the present application;

[0042] Fig.14 It is a schematic diagram of pasting an acceleration sensor on a transition section in a preferred embodiment of the present application;

[0043] Fig.15 It is a schematic diagram of the module structure of a turboshaft engine external piping vibration assessment system according to another embodiment of the present application. DETAILED DESCRIPTION

[0044] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0045] Reference Figure 4 The preferred embodiment of the present application provides a method for evaluating the vibration of an external piping of a turboshaft engine, comprising the following contents:

[0046] Step S1: performing finite element calculation and analysis on the external pipeline of the turboshaft engine, and correcting the connection stiffness through a knocking frequency test so that the calculated resonance frequency is consistent with the knocking resonance frequency, and obtaining the resonance frequency, vibration mode and vibration stress distribution of the external pipeline;

[0047] Step S2: Based on the vibration mode and vibration stress distribution of the external pipeline, after pasting the strain gauge at the point where the vibration stress is maximum in the direction of the vibration stress, carry out the maximum unbalance test of the whole machine, and evaluate the pipeline vibration risk based on the test results.

[0048] It can be understood that the external pipeline vibration assessment method of the turboshaft engine of this embodiment first carries out finite element calculation and analysis on the external pipeline, and corrects the connection stiffness through the knocking frequency test, taking into account the influence of the connection stiffness, corrects the finite element calculation model, makes the calculated resonance frequency consistent with the knocking resonance frequency, and obtains the finite element calculation results verified by the experiment, so that accurate pipeline vibration characteristics can be obtained, which is conducive to improving the accuracy of pipeline risk assessment, and only needs to conduct simple test comparison frequency results to verify and correct the finite element calculation model, without the need for complex modal tests. Then, based on the vibration mode and vibration stress distribution calculated by the modified finite element model, the maximum unbalance test of the whole machine is carried out after the strain gauge is pasted in the direction of the vibration stress at the maximum vibration stress point, and the pipeline vibration risk is evaluated according to the test results. The combination of finite element calculation and the maximum unbalance test of the whole machine is adopted, based on the accurate finite element calculation results combined with the installation of the whole machine, the vibration of the external pipeline can be more accurately simulated, which is conducive to further improving the accuracy of pipeline risk assessment.

[0049] It can be understood that in the step S1, the finite element calculation analysis is carried out on the external pipeline of the turboshaft engine, and the pipeline vibration shape diagram and the pipeline vibration stress distribution diagram at the first-order resonance frequency are obtained as follows: Figure 5 and Figure 6 As shown, in the finite element calculation process, the influence of the connection stiffness on the finite element calculation model is taken into account, and the connection stiffness is corrected by the knocking frequency test so that the calculated resonance frequency is consistent with the knocking resonance frequency, so that the resonance frequency, vibration mode and vibration stress distribution of the external pipeline can be accurately obtained. Among them, the process of correcting the connection stiffness by the knocking frequency test includes the following contents:

[0050] The knocking resonance frequency is obtained by knocking on the external pipe entity in the installed state, and then the connection stiffness between the adapter and the casing, the connection stiffness between the outer sleeve nut and the casing, and the connection stiffness between the clamp and the casing are changed during the finite element calculation, so that the calculated resonance frequency is consistent with the knocking resonance frequency, thereby correcting the finite element calculation model.

[0051] It is understandable that Figure 7As shown in the figure, the main conditions for pipeline finite element calculation include pipeline material data and constraint boundary conditions, wherein the pipeline material data include elastic modulus, mass, Poisson's ratio, etc., and the constraint boundary conditions include the connection stiffness between the adapter and the casing, the connection stiffness between the outer sleeve nut and the casing, and the connection stiffness between the clamp and the casing. When performing pipeline finite element calculation, different modal calculation results, i.e., resonance frequency and vibration mode, can be obtained by changing the connection stiffness of the joint / clamp. The knock frequency test directly obtains the knock resonance frequency by knocking the pipeline entity in the installed state of the whole machine. Therefore, by changing the connection stiffness of the joint / clamp input during the pipeline finite element calculation, the calculated resonance frequency obtained by the finite element calculation can be consistent with the knock frequency resonance frequency, so that the finite element calculation model can be corrected to obtain the calculation results verified by the experiment, and then, the vibration stress distribution and vibration mode of the external pipeline at the resonance frequency can be calculated according to the corrected finite element calculation model.

[0052] It can be understood that the present invention corrects the connection stiffness through the knocking frequency test, takes into account the influence of the connection stiffness, corrects the finite element calculation model, makes the calculated resonance frequency consistent with the knocking resonance frequency, and obtains the finite element calculation results verified by the experiment, so that accurate pipeline vibration characteristics can be obtained, which is conducive to improving the accuracy of pipeline risk assessment, and only requires simple test comparison frequency results to verify and correct the finite element calculation model, without the need for complex modal tests. Compared with the existing finite element calculation method that uses a fixed connection to calculate pipeline vibration characteristics, the accuracy of vibration risk assessment results is greatly improved.

[0053] It can be understood that in step S2, according to the vibration mode and vibration stress distribution calculated by the finite element calculation model modified in step S1, the strain gauge is pasted in the direction of the vibration stress at the point where the vibration stress is maximum, and verification is carried out along with the maximum unbalance test of the whole machine. Under the excitation condition of the maximum unbalance of the rotor, if the maximum vibration stress is less than the fatigue limit stress, it is determined that the external pipeline meets the design requirements, otherwise it is determined that there is a vibration risk in the external pipeline.

[0054] It can be understood that the present invention adopts a combination of finite element calculation and whole machine maximum unbalance test. Based on accurate finite element calculation results combined with the whole machine installation situation, it can more accurately simulate the vibration of the external pipeline, and take into account the impact of changes in the engine rotor exciting force on the pipeline vibration, which is conducive to further improving the accuracy of pipeline risk assessment.

[0055] In addition, if the strain gauge cannot be pasted at the point where the vibration stress is the largest, the strain gauge is pasted in the adjacent area where the vibration stress is the largest, and the vibration stress value at the point where the vibration stress is the largest is calculated based on the vibration stress value and the vibration stress distribution measured in the adjacent area. It can be understood that the vibration stress distribution obtained by the finite element calculation in step S1 is a cloud map, which can show the magnitude and direction of the vibration stress at different positions on the external pipeline, but the displayed vibration stress magnitude is only a relative value, not an absolute value. For example, the stress calculation at A is shown as 100MPa and at B is 50MPa, which only means that the vibration stress ratio at A and B is 2:1 at this time. The actual vibration stress magnitude is uncertain and can only be obtained by pasting the strain gauge for actual measurement. Therefore, if the strain gauge cannot be pasted at the point where the vibration stress is the largest, the strain gauge can be pasted in the adjacent area to measure the absolute value of the vibration stress, and then the proportional conversion is performed based on the proportional relationship in the vibration stress distribution cloud map to calculate the vibration stress value at the point where the vibration stress is the largest.

[0056] It can be understood that the present invention can directly measure the maximum vibration stress in the case where it is impossible to stick a strain gauge at the maximum vibration stress location, and can perform proportional conversion based on the vibration stress measurement results of the adjacent areas combined with the accurate vibration stress distribution results. Since the vibration stress distribution results are obtained based on finite element calculations, and the finite element calculation model is verified by knocking frequency test comparison, the accuracy of the vibration stress distribution results is guaranteed, so the accurate maximum vibration stress value can still be obtained, thereby improving adaptability.

[0057] In addition, if Figure 8 As shown, the turboshaft engine external piping vibration assessment method also includes the following contents:

[0058] Step S3: For external pipelines and weak locations of pipelines where strain gauges cannot be attached, a pipeline fatigue test piece with the same vibration shape, vibration stress distribution, resonance frequency and installation structure as the original pipeline is designed according to the resonance frequency, vibration shape and vibration stress distribution of the external pipeline, and a resonance residence test is performed.

[0059] Specifically, if the external pipeline is limited by its own structural design or the installation space of the external pipeline in the whole machine, for the pipeline where the strain gauge cannot be pasted, and the weak positions of the pipeline, such as welds, transitions, processing defects, etc., it is necessary to design a pipeline fatigue test piece for vibration retention test, and the vibration mode, vibration stress distribution, resonance frequency and installation structure of the pipeline fatigue test piece are consistent with the original external pipeline. For example, according to Figure 6The pipeline vibration stress distribution under the first-order resonance frequency can be found that relatively large stress appears near the joint and the clamp, so it is necessary to design a test piece whose local (i.e., near the joint and the clamp) vibration mode and stress distribution are consistent with the original pipeline under the same resonance frequency. In addition, for the convenience of design and processing, the pipeline fatigue test piece adopts a straight pipe structure with one end fixed and one end suspended, and the vibration mode, vibration stress distribution and resonance frequency of the test piece are adjusted by changing the length of the straight pipe. Wherein, since the constraint boundary conditions and pipeline material data have been determined in step S1, in order to ensure that the local (near the joint and the clamp) vibration mode and vibration stress distribution are consistent with the original pipeline when the test piece resonates, it can only be achieved by changing the test piece length, that is, controlling the length variable, so that the resonance frequency and vibration mode calculation results are consistent, and other conditions remain unchanged, such as the joint, pipeline radius, material, joint connection stiffness, etc. must be consistent. Moreover, since the pipeline fatigue test piece is a straight pipe, not a curved pipe, the circumferential angle of the pipeline can be easily adjusted during the subsequent test on the vibration table to make the vibration direction consistent with the excitation direction, so as to accurately simulate the location where the maximum vibration stress occurs. Fig. 9 As shown, the vibration mode of the weld end in the original pipeline is as follows Fig.10 As shown in the figure, the vibration mode of the weld end of the designed pipeline fatigue test piece is as follows Fig.11 As shown in the figure, the vibration stress distribution at the weld of the original pipeline is as follows Fig.12 As shown in Figure 2, the vibration stress distribution at the weld of the pipeline fatigue test piece is as follows: Fig.13 In addition, the specific pipeline design process is obtained through finite element calculation and analysis, and the specific process belongs to the prior art and will not be repeated here.

[0060] After processing the pipeline fatigue test piece, the test piece is connected to the vibration table through the adapter section, and the excitation direction of the vibration table is consistent with the principal stress direction of the vibration stress distribution result, that is, the excitation direction is consistent with the vibration mode direction, and the excitation frequency is set to the resonance frequency corresponding to the vibration mode of the test piece. The test duration is compared with the resonance dwell time to evaluate the high-cycle fatigue performance of the external pipeline. In addition, the adapter section must have sufficient rigidity, the first-order resonance frequency is above 2000Hz, and it will not affect the vibration mode of the test piece after being connected to the test piece. Among them, the resonance dwell time threshold is calculated based on the following formula:

[0061]

[0062] Wherein, T represents the resonance dwell time, ω represents the dwell frequency, i.e., the resonance frequency. If the resonance dwell time exceeds the time threshold and the test piece does not produce crack damage, it is determined that the high cycle fatigue life requirement is met; otherwise, it is determined that the high cycle fatigue life requirement is not met.

[0063] It can be understood that pipelines are generally steel metal parts. The airworthiness requirements stipulate that if the test piece is subjected to 10 to the seventh power cyclic stress under resonance conditions without crack damage, it can be considered that its high cycle fatigue life under this condition meets the airworthiness requirements.

[0064] In addition, considering that the pipeline fatigue test piece is a component test, in order to further improve the accuracy, such as Fig.14 As shown, an acceleration sensor can also be attached to the adapter section of the pipeline test piece, and the acceleration sensor is compared with the acceleration sensor near the pipeline during the maximum unbalance test of the whole machine in step S2. By adjusting the exciting force of the vibration table, the acceleration values ​​of the two are kept consistent, thereby ensuring that the exciting force of the resonance is basically consistent, avoiding the influence of the exciting force of the vibration table, and verifying more fully. Pipeline vibration risk assessment is more accurate.

[0065] like Fig.15 As shown, another embodiment of the present invention further provides a turboshaft engine external piping vibration assessment system, preferably using the turboshaft engine external piping vibration assessment method as described above, comprising:

[0066] Finite element calculation and correction module, used to carry out finite element calculation and analysis on the external piping of the turboshaft engine, and correct the connection stiffness through knocking frequency test, so that the calculated resonance frequency is consistent with the knocking resonance frequency, and the resonance frequency, vibration mode and vibration stress distribution of the external piping are obtained;

[0067] The pipeline vibration risk assessment module is used to conduct a maximum unbalance test of the whole machine based on the vibration mode and vibration stress distribution of the external pipeline, after pasting the strain gauge in the direction of the vibration stress at the point with the maximum vibration stress, and evaluate the pipeline vibration risk according to the test results.

[0068] It can be understood that the external pipeline vibration assessment system of the turboshaft engine of this embodiment first carries out finite element calculation and analysis on the external pipeline, and corrects the connection stiffness through the knocking frequency test, taking into account the influence of the connection stiffness, corrects the finite element calculation model, makes the calculated resonance frequency consistent with the knocking resonance frequency, and obtains the finite element calculation results verified by the experiment, so that accurate pipeline vibration characteristics can be obtained, which is conducive to improving the accuracy of pipeline risk assessment, and only needs to conduct simple test comparison frequency results to verify and correct the finite element calculation model, without the need for complex modal tests. Then, based on the vibration mode and vibration stress distribution calculated by the modified finite element model, the maximum unbalance test of the whole machine is carried out after the strain gauge is pasted in the direction of the vibration stress at the maximum vibration stress point, and the pipeline vibration risk is evaluated according to the test results. The combination of finite element calculation and the maximum unbalance test of the whole machine is adopted, based on the accurate finite element calculation results combined with the installation of the whole machine, the vibration of the external pipeline can be simulated more accurately, which is conducive to further improving the accuracy of pipeline risk assessment.

[0069] In addition, the turboshaft engine external piping vibration assessment system further includes:

[0070] The high-cycle fatigue life assessment module is used for external pipelines and weak locations where strain gauges cannot be attached. According to the resonance frequency, vibration mode and vibration stress distribution of the external pipeline, the pipeline fatigue test piece with the same vibration mode, vibration stress distribution, resonance frequency and installation structure as the original pipeline is designed, and a resonance residence test is performed.

[0071] It can be understood that the various modules of the system embodiment correspond to the various steps of the above method embodiment, so the specific working principles of each module are not repeated here, and the corresponding references can be made to the various steps of the above method embodiment.

[0072] In addition, another embodiment of the present invention further provides an electronic device, including a processor and a memory, wherein the memory stores a computer program, and the processor executes the steps of the above method by calling the computer program stored in the memory.

[0073] In addition, another embodiment of the present invention further provides a computer-readable storage medium for storing a computer program for performing vibration assessment on external piping of a turboshaft engine, wherein the computer program executes the steps of the method described above when running on a computer.

[0074] The general form of computer readable storage media includes: floppy disk, flexible disk, hard disk, magnetic tape, any other magnetic medium, CD-ROM, any other optical medium, punch cards, paper tape, any other physical medium with a pattern of holes, random access memory (RAM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), flash erasable programmable read-only memory (FLASH-EPROM), any other memory chip or cartridge, or any other medium that can be read by a computer. The instructions can further be transmitted or received by a transmission medium. The term transmission medium can include any tangible or intangible medium that can be used to store, encode or carry instructions for execution by a machine, and includes digital or analog communication signals or other intangible media that facilitate the communication of the above instructions. Transmission media include coaxial cables, copper wires and optical fibers, which include the wires of a bus used to transmit a computer data signal.

[0075] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of complete hardware embodiments, complete software embodiments, or embodiments in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code. The scheme in the embodiments of the present application can be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0076] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0077] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 Process or multiple flows Program and / or Box Figure 1 Box or Functions specified in multiple boxes.

[0078] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0079] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0080] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

[0081] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for evaluating the vibration of an external pipeline of a turboshaft engine, characterized in that: Includes the following: Finite element analysis was performed on the external piping of the turboshaft engine, and the connection stiffness was corrected through a knocking frequency test so that the calculated resonance frequency was consistent with the knocking resonance frequency, and the resonance frequency, vibration mode and vibration stress distribution of the external piping were obtained; Based on the vibration mode and vibration stress distribution of the external pipeline, after pasting the strain gauge at the point with the maximum vibration stress in the direction of the vibration stress, the maximum unbalance test of the whole machine is carried out, and the pipeline vibration risk is evaluated based on the test results; The process of correcting the connection stiffness by the knock frequency test includes the following contents: The knocking resonance frequency is obtained by knocking on the external pipe entity in the installed state, and then the connection stiffness between the adapter and the casing, the connection stiffness between the outer sleeve nut and the casing, and the connection stiffness between the clamp and the casing are changed during the finite element calculation, so that the calculated resonance frequency is consistent with the knocking resonance frequency, thereby correcting the finite element calculation model.

2. The turboshaft engine external piping vibration assessment method according to claim 1, characterized in that: If the strain gauge cannot be pasted at the location where the vibration stress is maximum, the strain gauge shall be pasted in the adjacent area where the vibration stress is maximum, and the vibration stress value at the location where the vibration stress is maximum shall be calculated by proportional conversion based on the vibration stress value and vibration stress distribution measured in the adjacent area.

3. The turboshaft engine external piping vibration assessment method according to claim 1, characterized in that: Also included are the following: For external pipelines and weak locations where strain gauges cannot be attached, pipeline fatigue test pieces with the same vibration shape, vibration stress distribution, resonance frequency and installation structure as the original pipeline are designed according to the resonance frequency, vibration shape and vibration stress distribution of the external pipeline, and a resonance residence test is carried out.

4. The turboshaft engine external piping vibration assessment method according to claim 3, characterized in that: The pipeline fatigue test piece adopts a straight tube structure with one end fixed and the other end suspended, and the vibration mode, vibration stress distribution and resonance frequency of the test piece are adjusted by changing the length of the straight tube.

5. The turboshaft engine external piping vibration assessment method according to claim 3, characterized in that: The resonance dwell time threshold is calculated based on the following formula: Wherein, T represents the resonance dwell time, ω represents the dwell frequency, and if the resonance dwell time exceeds the time threshold and the test piece does not produce crack damage, it is determined that the high cycle fatigue life requirement is met.

6. A turboshaft engine external piping vibration assessment system, using the turboshaft engine external piping vibration assessment method according to any one of claims 1 to 5, characterized in that: include: Finite element calculation and correction module, used to carry out finite element calculation and analysis on the external piping of the turboshaft engine, and correct the connection stiffness through knocking frequency test, so that the calculated resonance frequency is consistent with the knocking resonance frequency, and the resonance frequency, vibration mode and vibration stress distribution of the external piping are obtained; The pipeline vibration risk assessment module is used to conduct a maximum unbalance test of the whole machine based on the vibration mode and vibration stress distribution of the external pipeline, after pasting the strain gauge in the direction of the vibration stress at the point with the maximum vibration stress, and evaluate the pipeline vibration risk according to the test results.

7. A turboshaft engine external piping vibration assessment system as claimed in claim 6, characterized in that: Also includes: The high-cycle fatigue life assessment module is used for external pipelines and weak locations where strain gauges cannot be attached. According to the resonance frequency, vibration mode and vibration stress distribution of the external pipeline, the pipeline fatigue test piece with the same vibration mode, vibration stress distribution, resonance frequency and installation structure as the original pipeline is designed, and a resonance residence test is performed.

8. An electronic device, characterized in that: The method comprises a processor and a memory, wherein the memory stores a computer program, and the processor executes the steps of the method according to any one of claims 1 to 5 by calling the computer program stored in the memory.

9. A computer-readable storage medium for storing a computer program for vibration assessment of an external piping of a turboshaft engine, characterized in that: When the computer program is run on a computer, the steps of the method according to any one of claims 1 to 5 are executed.

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