A quick strength analysis method applied to a rotor of an axial flow type rotating machine

Abstract

The application discloses a kind of fast strength analysis methods applied to rotor of axial flow type rotating machinery, S1, establishes rotor entity model;S2, carries out strength analysis to rotor entity model, wherein rotor disc has the geometric feature of n to be reserved, one is reserved and is taken as center to the rotor entity model along the circumferential 360° / n range sector domain of cutting, two circumferential sides of calculation domain are set periodic boundary condition;S3, finite element model is established to sector domain, corresponding load is applied with actual working condition, deformation and stress field result are obtained, and then strength analysis result is obtained.It can save the calculation time most under the premise of guaranteeing the accuracy of calculation, improve analysis efficiency, simplify the arrangement of entity modeling and finite element modeling, reduce the time of calculation and analysis;The detailed component structure of fault area is reserved, the necessary geometric feature is restored, and more accurate strength analysis result of fault component is obtained.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of strength analysis of rotating machinery, and relates to a quick strength analysis method applied to a rotor of an axial-flow rotating machinery. BACKGROUND

[0002] The axial-flow rotating machinery is a mechanical device for realizing functions through rotation of a rotor, and common examples include an aero-engine, a heavy-duty gas turbine and a compressor. The rotor, as a core component of the rotating machinery, is generally composed of a main shaft, a disk, a blade, a bolt and the like, has a complex structure and variable loads, and is a main source of faults of the rotating machinery. The rotor fault is often related to alternating stress borne by the rotor, and the rotor fault usually needs to be repaired after shutdown, which causes economic losses in varying degrees. Therefore, the strength analysis of the rotor of the rotating machinery has very important practical significance.

[0003] The traditional strength analysis program of the rotor of the axial-flow rotating machinery is complex, emphasizes accuracy of analysis data, and needs multiple means to verify each other. Even the numerical calculation method with high efficiency needs to consume a large amount of time to establish an entity model and a grid corresponding to the entity model to restore the complex geometric structure of the rotor of the rotating machinery. The more features are restored, the greater the grid encryption is, and the more the calculation time is consumed. The longer the strength analysis cycle is, the greater the economic loss caused by the rotor fault is. SUMMARY

[0004] The application aims at overcoming the defects of the prior art, and provides a quick strength analysis method applied to the rotor of the axial-flow rotating machinery, which reduces the time of calculation and analysis, can quickly complete fault qualitative analysis, and helps to reduce the loss caused by fault shutdown.

[0005] To achieve the above object, the application adopts the following technical scheme:

[0006] A quick strength analysis method applied to the rotor of the axial-flow rotating machinery comprises the following processes:

[0007] S1, an entity model of the rotor is established;

[0008] S2, strength analysis is performed on the entity model of the rotor, wherein the rotor disk has n geometric features to be retained, one of the geometric features is retained and taken as a center to cut a sector calculation domain of 360° / n range along a circumferential direction of the entity model of the rotor, and periodic boundary conditions are set on two circumferential sides of the sector calculation domain;

[0009] S3, a finite element model is established for the sector calculation domain, a load corresponding to an actual working condition is applied, deformation and stress field results are obtained, and then strength analysis results are obtained.

[0010] Preferably, in S1, the specific process of establishing the rotor entity model is: for the components in the fault area, the geometric features and the contact surfaces between adjacent geometric structures are retained; for the non-fault components, the contact surfaces between the components are ignored and the components are regarded as a continuous body; the continuous body and the individual entities of the fault area are combined into a complete rotor entity model according to the assembly relationship.

[0011] Preferably, before S1, the mass of the blade is equivalent to the corresponding disc by using the lumped mass method.

[0012] Preferably, in S2, n is 4-20.

[0013] Preferably, in S3, the load corresponding to the actual working condition is applied to the components in the fault area, and the deformation and stress field results of the bearing surface and the contact surface of the components in the fault area are obtained.

[0014] Preferably, in S3, the mesh of the components in the fault area whose geometric features are restored is encrypted, and the number of meshes of the entity model of other parts is reduced by 30-50%.

[0015] A fast strength analysis system applied to a rotor of an axial flow rotary machine, comprising:

[0016] An entity model establishing module, configured to establish a rotor entity model;

[0017] A sector calculation domain establishing module, configured to perform strength analysis on the rotor entity model, wherein the disc of the rotor has n geometric features to be retained, one of which is retained and taken as a center to cut a sector calculation domain of 360° / n range along the circumference of the rotor entity model, and periodic boundary conditions are set on the two circumferential sides of the calculation domain;

[0018] A strength analysis module, configured to establish a finite element model for the sector calculation domain, apply a load corresponding to an actual working condition, obtain deformation and stress field results, and then obtain strength analysis results.

[0019] A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the fast strength analysis method applied to the rotor of the axial flow rotary machine according to any one of the above.

[0020] A computer readable storage medium, which stores a computer program, wherein the computer program is executable by a processor to implement the steps of the fast strength analysis method applied to the rotor of the axial flow rotary machine according to any one of the above.

[0021] Compared with the prior art, the present application has the following beneficial effects:

[0022] The present application preserves one of the geometric features of the rotor wheel disc and takes it as the center to cut the rotor entity model along the circumferential direction to obtain a 360° / n range of sector calculation domains, and sets periodic boundary conditions on the two circumferential sides of the calculation domain, so that the calculation time can be saved to the maximum extent under the premise of ensuring the calculation accuracy, the analysis efficiency is improved, the arrangement of entity modeling and finite element modeling is simplified, and the calculation and analysis time is reduced; and the finite element model of the sector calculation domain is established to perform load stress analysis, the detailed component structure of the fault area is preserved, the necessary geometric features are restored, and the calculation accuracy is higher than that of the simplified continuum rotor modeling, and more accurate strength analysis results of the fault component can be obtained. The demand of shortening the analysis time in the engineering field is fully considered, and the necessary geometric features for strength analysis are preserved, so that the strength analysis results of the axial flow type rotating machinery rotor can be obtained quickly and accurately, and a method for improving the fault analysis efficiency is provided.

[0023] Further, the detailed geometric features and contact surfaces are preserved in the entity modeling of the components that need to be analyzed, so that the influence of the load on the stress distribution and deformation of the contact surface can be accurately simulated, and the entity model of the other components is combined as a whole, so that the accuracy and required time of deformation, stress field and other calculations can be better balanced, and the calculation resources can also be saved.

[0024] Further, the mass of the blade is equivalent to the corresponding disc by using the lumped mass method, so that the calculation amount can be reasonably reduced and the calculation time can be saved.

[0025] Further, the grid of the component whose geometric features are restored is encrypted, the grid size after encryption is 1% to 10% of the characteristic length of the component, the calculation focus is deviated to the fault area, and the calculation accuracy is improved. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 The flow chart of the flow type rotating machinery rotor fast strength analysis method of the present application;

[0027] Figure 2 The disc and shaft combined modeling schematic diagram of the present application;

[0028] Figure 3 The sector calculation domain schematic diagram of the present application;

[0029] Figure 4 The disc pull rod bolt hole position schematic diagram of the present application. DETAILED DESCRIPTION

[0030] The present application will be further described in detail below in combination with the drawings:

[0031] As Figure 1As shown, the application of the quick strength analysis method for the rotor of the axial flow rotary machine described in the application comprises the following processes:

[0032] Step 1, a large number of blades are arranged on the wheel disc of the axial flow rotary machine, such as compressor blades, turbine blades, etc., usually in order to prevent resonance, the number of these blades cannot be divided by the number of the geometric features of the wheel disc, for the geometric structure of the outer edge of the wheel disc, the mass concentration method is adopted to equivalently integrate the mass of the wheel disc to the blades, to provide conditions for the subsequent calculation of the sector domain and to improve the calculation speed.

[0033] Step 2, for non-fault components, such as wheel discs, pull rod bolts, nuts and other components away from the fault area, the combined entity modeling can be carried out, that is, the contact surfaces between these components are ignored and they are regarded as a continuum; for the components in the fault area, the detailed geometric features and the contact surfaces between the adjacent geometric structures are retained to accurately simulate the influence of the load on the stress distribution and deformation of the contact surface; in this way, the accuracy and the required time of the deformation, stress field and other calculations can be better balanced, and the calculation resources can also be saved. The simplified continuous component entity and the separate entity components in the fault area are combined into a complete rotor entity model according to the assembly relationship.

[0034] Step 3, since the wheel disc of the rotary machine often has n geometric features that need to be retained, n is generally 4-20, when the strength of the rotary machine rotor is analyzed, one or a group of them can be retained and taken as the center to cut the 360° / n range of the sector calculation domain from the rotor entity model obtained in step 2, and the periodic boundary conditions are set on the two circumferential sides of the calculation domain, this method can maximize the saving of calculation time and improve the analysis efficiency on the premise of ensuring the accuracy of the calculation.

[0035] Arrangement 4, the structured grid is made according to the geometric parameters of the sector calculation domain obtained in step 3 to establish the finite element model, the components with detailed restored geometric features in the fault area are appropriately encrypted, and the grid size after encryption is 1%-10% of the feature length of the component, and the grid making precision of the continuum model of other parts can be appropriately reduced, the load of the rotor finite element model is applied to obtain the deformation and stress distribution of the key positions such as the bearing surface and the contact surface of the components in the fault area, and the quantitative strength analysis is carried out accordingly.

[0036] The following examples are the specific strength analysis processes of the rotor of the axial flow rotary machine using the above method:

[0037] Step 1: The axial-flow rotating mechanical disk has a large number of blades, such as the compressor and turbine blades in the embodiment. The number of these blades cannot be divided by the number of bolt holes on the disk. In order to establish the subsequent sector-shaped calculation domain, the mass of these blades is concentrated and the mass of the whole is equivalent to the disk on which the blades are located.

[0038] Step 2, for non-faulty components, such as Figure 2 The non-fault-level rotor shown can be modeled as a single solid, ignoring the contact surfaces between its components and treating it as a continuum. For components in the fault region, such as the tie rod bolts in the embodiment, detailed geometric features and contact surfaces with adjacent geometries are retained. This approach better balances the accuracy and time required for calculations of deformation and stress fields, and also helps save computational resources. The simplified spindle solid and the tie rod bolt solid components in the fault region are combined according to their assembly relationships to form a complete rotor solid model.

[0039] Step 3: Since the rotor of rotating machinery often has n geometric features that need to be retained (12 tie rod bolt holes in this example), these structures exhibit sector symmetry with respect to the axis. When performing strength analysis on the rotor of the rotating machinery, other identical bolt holes can be omitted, retaining only one and using it as the center to circumferentially cut 360° / n from the rotor solid model obtained in Step 2. In this example, this is a sector-shaped computational domain within a range of 30°. Figure 3 As shown, periodic boundary conditions are set on the two circumferential sides of the computational domain to improve the efficiency of rotor strength analysis.

[0040] Arrangement 4: Based on the geometric parameters of the sector computational domain obtained in step 3, create a structured mesh to establish the finite element model, such as... Figure 4 As shown, the geometric features of the fault area are restored in detail and the mesh is appropriately densified. The mesh production accuracy of other parts can be reduced. The rotor finite element model is subjected to loads that conform to the actual working conditions to obtain the deformation and stress distribution of key positions such as the bearing surface and contact surface of the fault area component. Based on this, quantitative strength analysis is carried out.

[0041] The following are embodiments of the apparatus of the present invention, which can be used to execute embodiments of the method of the present invention. For details not omitted in the apparatus embodiments, please refer to the embodiments of the method of the present invention.

[0042] In another embodiment of the present invention, a rapid strength analysis system for axial-flow rotating machinery rotors is provided. This rapid strength analysis system for axial-flow rotating machinery rotors can be used to implement the aforementioned rapid strength analysis method for axial-flow rotating machinery rotors. Specifically, the rapid strength analysis for axial-flow rotating machinery rotors includes a solid model establishment module, a sector calculation domain establishment module, and a strength analysis module.

[0043] The entity model establishing module is configured to establish a rotor entity model; the sector calculation domain establishing module is configured to perform strength analysis on the rotor entity model, wherein the rotor disc has n geometric features to be reserved, one of which is reserved and taken as a center to cut a sector calculation domain of 360° / n range along the circumferential direction of the rotor entity model, and periodic boundary conditions are set for two circumferential sides of the calculation domain; and the strength analysis module is configured to establish a finite element model for the sector calculation domain, apply a load corresponding to an actual working condition, obtain deformation and stress field results, and further obtain a strength analysis result.

[0044] In another embodiment of the present application, a terminal device is provided, which comprises a processor and a memory, the memory is configured to store a computer program, the computer program comprises program instructions, and the processor is configured to execute the program instructions stored in the computer storage medium. The processor can be a central processing unit (CPU), and can also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, which is suitable for implementing one or more instructions, and is particularly suitable for loading and executing one or more instructions to implement a corresponding method flow or a corresponding function. The processor in the embodiment of the present application can be used for the operation of the fast strength analysis method of the axial flow type rotating machinery rotor, which comprises: S1: establishing a rotor entity model; S2: performing strength analysis on the rotor entity model, wherein the rotor disc has n geometric features to be reserved, one of which is reserved and taken as a center to cut a sector calculation domain of 360° / n range along the circumferential direction of the rotor entity model, and periodic boundary conditions are set for two circumferential sides of the calculation domain; S3: establishing a finite element model for the sector calculation domain, applying a load corresponding to an actual working condition, obtaining deformation and stress field results, and further obtaining a strength analysis result.

[0045] In another embodiment, the present application also provides a computer readable storage medium (Memory), which is a memory device in the terminal device, used for storing programs and data. It can be understood that the computer readable storage medium herein can include the built-in storage medium in the terminal device, and of course can also include the expansion storage medium supported by the terminal device. The computer readable storage medium provides a storage space, which stores the operating system of the terminal. Moreover, one or more instructions suitable for being loaded and executed by the processor are also stored in the storage space, and the instructions can be one or more computer programs (including program codes). It should be noted that the computer readable storage medium herein can be a high-speed RAM memory, or a non-volatile memory, such as at least one disk memory.

[0046] The one or more instructions stored in the computer readable storage medium can be loaded and executed by the processor to implement the corresponding steps of the above-mentioned embodiments related to the fast strength analysis method applied to the rotor of the axial flow rotary machine. The one or more instructions stored in the computer readable storage medium are loaded and executed by the processor to perform the following steps: S1: establishing a rotor entity model; S2: performing strength analysis on the rotor entity model, wherein the rotor disc has n geometric features to be retained, one of which is retained and taken as the center to cut the 360° / n range of the sector calculation domain along the circumferential direction of the rotor entity model, and the two circumferential sides of the calculation domain are provided with periodic boundary conditions; S3: establishing a finite element model for the sector calculation domain, applying a load corresponding to the actual working condition, obtaining the deformation and stress field results, and then obtaining the strength analysis results.

[0047] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can adopt a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. 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.) containing computer usable program codes.

[0048] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks. Figure 1 one or more flow or blocks Figure 1 one or more flow or blocks

[0049] These computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture including instructions which implement the function specified in the flowchart block or blocks. Figure 1 one or more flow or blocks Figure 1 one or more flow or blocks

[0050] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks. Figure 1 one or more flow or blocks Figure 1 one or more flow or blocks

[0051] Finally, it should be noted that the above-mentioned embodiments are merely intended to illustrate the technical solutions of the present application, but not to limit the present application. Although the present application has been described in detail with reference to the above-mentioned embodiments, those skilled in the art should understand that the technical solutions of the present application can still be modified or equivalent replaced without departing from the spirit and scope of the present application, and any modification or equivalent replacement should be covered within the protection scope of the claims of the present application.

Claims

1. A rapid strength analysis method for rotors of axial-flow rotating machinery, characterized in that, Includes the following processes: S1. The mass of the blades is equivalent to that of their corresponding disks using the lumped mass method to establish a rotor solid model. The specific process of establishing the rotor solid model is as follows: For the components in the fault area, retain the geometric features and the contact surfaces with adjacent geometric structures; for non-faulty components, ignore the contact surfaces between these components and treat them as a continuum; combine the continuum and the individual solids of the fault area according to the assembly relationship to form a complete rotor solid model; S2, perform strength analysis on the rotor solid model, where the rotor disk has n geometric features to be retained. One of them is retained and a fan-shaped computational domain of 360° / n is cut off along the circumference of the rotor solid model with it as the center. Periodic boundary conditions are set on the two circumferential sides of the computational domain. S3 establishes a finite element model for the sector-shaped computational domain, applies loads corresponding to the actual working conditions, obtains deformation and stress field results, and then obtains strength analysis results.

2. The rapid strength analysis method for axial-flow rotating machinery rotors according to claim 1, characterized in that, In S2, n ranges from 4 to 20.

3. The rapid strength analysis method for axial-flow rotating machinery rotors according to claim 1, characterized in that, In S3, loads corresponding to actual working conditions are applied to the components in the fault area to obtain the deformation and stress field results of the bearing surface and contact surface of the components in the fault area.

4. The rapid strength analysis method for axial-flow rotating machinery rotors according to claim 1, characterized in that, In S3, the mesh of the component whose geometric features of the fault area have been restored is refined, and the scale of the refined mesh is 1% to 10% of the feature length of the component.

5. A rapid strength analysis system for rotors of axial-flow rotating machinery, characterized in that, include: The solid model building module is used to establish a rotor solid model by using the lumped mass method to equate the mass of the blades to their corresponding disks. The specific process of establishing the rotor solid model is as follows: For the components in the fault area, retain the geometric features and the contact surfaces with adjacent geometric structures; for non-faulty components, ignore the contact surfaces between these components and treat them as a continuum; combine the continuum and the individual solids of the fault area according to the assembly relationship to form a complete rotor solid model; The sector computational domain establishment module is used to perform strength analysis on the rotor solid model. The rotor disk has n geometric features to be retained. One of them is retained and a sector computational domain of 360° / n range is extracted from the rotor solid model around it. Periodic boundary conditions are set on the two circumferential sides of the computational domain. The strength analysis module is used to establish a finite element model of the sector computational domain, apply loads corresponding to the actual working conditions, obtain deformation and stress field results, and then obtain strength analysis results.

6. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the rapid strength analysis method for axial-flow rotating machinery rotors as described in any one of claims 1 to 4.

7. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the rapid strength analysis method for axial-flow rotating machinery rotors as described in any one of claims 1 to 4.

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