Method and device for calculating circumferential contact stiffness of aero-engine flange-stop structure

Abstract

The present application relates to the technical field of mechanical engineering, specifically to a kind of aero-engine flange-cuff structure ring contact stiffness calculation method and device, the method combines fractal contact theory, boundary element algorithm and discrete Iwan model, establishes the ring contact stiffness calculation model of flange-cuff connection structure, the uniform pressure of each sub-region of contact interface is obtained by the way of combining finite element method and thick-walled cylinder theory. After obtaining the contact state of each sub-region using fractal contact theory and boundary element algorithm, the ring contact stiffness of the entire cuff-bolt structure is calculated by combining discrete Iwan model. The actual stress distribution of flange-cuff connection structure in aero-engine rotor and the rough surface topography of mating interface are fully considered, and the problem of difficult theoretical modeling of ring contact stiffness of flange-cuff connection structure in aero-engine rotor is solved.

Description

Technical Field

[0001] This invention relates to the field of mechanical engineering technology, and in particular to a method and apparatus for calculating the circumferential contact stiffness of an aero-engine flange-stop structure. Background Technology

[0002] As the heart of an aircraft, the aero-engine is hailed as the "crown jewel of industry" and a typical representative of high-performance electromechanical equipment. Assembly is a crucial step in the aero-engine development process; however, sudden vibration changes in the aero-engine rotor during engine testing have become a bottleneck restricting the assembly pass rate. Studying the dynamic behavior of the aero-engine rotor under the influence of assembly form and force factors is a prerequisite for optimizing and controlling high-performance assembly processes. The basic contact characteristic parameters of the aero-engine rotor, such as connection stiffness and damping, have a significant impact on the system's dynamic response, and the interface contact stiffness accounts for 50%-75% of the total stiffness of the aero-engine. Therefore, considering the influence of the rough surface morphology of the mating interface and the actual stress distribution, accurately calculating the circumferential contact stiffness of the aero-engine rotor's stop-bolt connection structure is crucial for predicting the dynamic behavior of the aero-engine rotor during service. Summary of the Invention

[0003] To address the aforementioned issues, embodiments of the present invention provide a method and apparatus for calculating the circumferential contact stiffness of an aero-engine flange-stop structure.

[0004] One aspect of this invention provides a method for calculating the circumferential contact stiffness of an aero-engine flange-stop structure, comprising:

[0005] The pressure distribution on the flange end face and the pressure distribution on the interference surface of the engine rotor are obtained. Based on the obtained pressure distribution, the flange end face and the interference surface are divided into multiple sub-regions, and the normal contact pressure of each sub-region is obtained.

[0006] Calculate the dimensionless actual contact area of ​​each sub-region, and then use the normal contact pressure and the dimensionless actual contact area to calculate the normal contact force and tangential contact stiffness of each sub-region.

[0007] Each sub-region is equivalent to a Jenkins element in the discrete Iwan model. The normal contact force of the sub-region is used as the normal pressure of the Jenkins element, and the tangential contact stiffness of the sub-region is used as the stiffness of the spring of the Jenkins element. A predetermined circumferential excitation displacement is input into the discrete Iwan model to obtain the tangential response force of the discrete Iwan model. The circumferential contact stiffness of the flange-stop structure is obtained by differentiating the tangential response force with respect to the circumferential excitation displacement.

[0008] Optionally, the process of obtaining the pressure distribution on the flange end face includes: using the finite element analysis method to obtain the pressure distribution on the flange end face.

[0009] Optionally, the process of obtaining the pressure distribution of the interference surface of the stop includes: obtaining the root clearance of the stop through the finite element analysis method, and obtaining the pressure distribution of the interference surface of the stop based on the thick-walled cylinder theory using the root clearance of the stop.

[0010] Optionally, the process of calculating the dimensionless actual contact area of ​​each sub-region includes:

[0011] Fractal theory is used to describe the random roughness characteristics of the surface of a sub-region, and the surface morphology of the sub-region, including fractal dimension and fractal roughness, is obtained.

[0012] Obtain the material parameters of the sub-region, including elastic modulus, Poisson's ratio, yield strength, and tangent modulus;

[0013] By inputting the surface morphology and material parameters into a semi-analytical algorithm based on the boundary element method, the dimensionless actual contact area of ​​the sub-region is obtained.

[0014] Optionally, the process of calculating the normal contact force and tangential contact stiffness of each sub-region using the normal contact pressure and the dimensionless actual contact area includes:

[0015] Construct an island distribution function using the dimensionless actual contact area of ​​the sub-region;

[0016] Hertzian contact theory was used to calculate the elastoplastic contact force and deformation of a single micro-protrusion in a sub-region. Based on the different heights of the micro-protrusions, the contact states of the micro-protrusions were classified into pure elastic deformation, elastoplastic deformation, and pure plastic deformation.

[0017] The distribution functions of micro-protrusions and islands under the same contact state are integrated simultaneously, and the integral results corresponding to micro-protrusions under different contact states are added together to obtain the normal contact force and tangential contact stiffness of the sub-region.

[0018] Optionally, the discrete Iwan model consists of several parallel Jenkins units, each with different stiffness and critical sliding force.

[0019] Another aspect of this invention provides a device for calculating the circumferential contact stiffness of an aero-engine flange-stop structure, comprising:

[0020] The sub-region pressure distribution module is used to obtain the pressure distribution of the flange end face and the pressure distribution of the interference surface of the stop in the aero-engine rotor. Based on the obtained pressure distribution, the flange end face and the interference surface of the stop are divided into multiple sub-regions, and the normal contact pressure of each sub-region is obtained.

[0021] The sub-region contact state module is used to calculate the dimensionless actual contact area of ​​each sub-region, and then use the normal contact pressure and the dimensionless actual contact area to calculate the normal contact force and tangential contact stiffness of each sub-region.

[0022] The flange-stop structure contact stiffness module is used to represent each sub-region as an equivalent Jenkins element in a discrete Iwan model. The normal contact force of the sub-region is used as the normal pressure of the Jenkins element, and the tangential contact stiffness of the sub-region is used as the spring stiffness of the Jenkins element. A predetermined circumferential excitation displacement is input into the discrete Iwan model to obtain the tangential response force of the discrete Iwan model. The circumferential contact stiffness of the flange-stop structure is obtained by differentiating the tangential response force with respect to the circumferential excitation displacement.

[0023] In another aspect of the present invention, an electronic device is also provided, including a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus;

[0024] Memory is used to store processor-executable instructions;

[0025] The processor, when executing instructions stored in memory, implements the above-mentioned method for calculating the circumferential contact stiffness of the aero-engine flange-stop structure.

[0026] Compared with existing technologies, the advantages of this invention are as follows: By combining fractal contact theory, boundary element algorithm, and discrete Iwan model, a calculation model for the circumferential contact stiffness of the flange-stop connection structure is established. By combining the finite element method and thick-walled cylinder theory, the uniformly distributed pressure of each sub-region of the contact interface is obtained. After obtaining the contact state of each sub-region using fractal contact theory and boundary element algorithm, the circumferential contact stiffness of the entire stop-bolt structure is calculated by combining the discrete Iwan model. The invention fully considers the actual stress distribution of the flange-stop connection structure in the aero-engine rotor and the rough surface morphology of the mating interface, thus solving the problem of theoretically modeling the circumferential contact stiffness of the flange-stop connection structure in the aero-engine rotor. Attached Figure Description

[0027] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, are not intended to limit the scope of the invention. In the drawings:

[0028] Figure 1 The flowchart shows the overall process for calculating the circumferential contact stiffness of the aero-engine flange-stop structure provided in this embodiment of the invention.

[0029] Figure 2 A simplified diagram of the aero-engine rotor structure provided in an embodiment of the present invention;

[0030] Figure 3 This is a schematic diagram of the circumferential contact stiffness calculation device for the aero-engine flange-stop structure provided in an embodiment of the present invention.

[0031] Figure 4 This is a schematic diagram of the electronic device structure provided in an embodiment of the present invention. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the embodiments and accompanying drawings. Here, the illustrative embodiments and descriptions of this invention are used to explain the invention, but are not intended to limit the invention.

[0033] See Figure 1 The method for calculating the circumferential contact stiffness of an aero-engine flange-stop structure provided in this embodiment of the invention includes:

[0034] S1. Obtain the pressure distribution of the flange end face and the pressure distribution of the interference fit surface in the aero-engine rotor. Based on the obtained pressure distribution, divide the flange end face and the interference fit surface into multiple sub-regions and obtain the normal contact pressure of each sub-region.

[0035] See Figure 2 This invention simplifies the structure of the aero-engine rotor by modeling and analyzing only the flange end face and the interference fit surface of the stop within the single bolt sector area. The contact force and contact stiffness of the rough surface are calculated using fractal contact theory. However, the contact pressure of the flange end face and the interference fit surface exhibits obvious non-uniform characteristics. Therefore, this invention uses a combination of finite element simulation and thick-walled cylinder theory to obtain the mathematical expression of the interface contact pressure and divides the region into sub-regions to calculate the uniformly distributed pressure. That is, the normal contact force is considered to be uniform in each sub-region.

[0036] During implementation, the pressure distribution on the flange end face is obtained using the finite element analysis method.

[0037] For interference fit pressure at the stop, the thick-walled cylinder theory is often used to calculate the interference fit force between the shaft and the hub. Due to the axial symmetry of the shaft and hub structure and the distribution of contact pressure, the interference fit can be simplified to a plane strain problem. Furthermore, since the interference is much smaller than the part size, the plane strain problem can be further considered as a non-uniform load acting on the straight boundary of a semi-infinite plate.

[0038] However, the interference fit of the stop is different from the interference fit between the shaft and the hub. Due to the effect of the bolt preload, the interference fit of the stop has a non-ideal root clearance. This invention considers the influence of the root clearance on the interference force of the stop, uses the finite element method to extract the value of the root clearance, and then substitutes it into the theoretical formula of the thick-walled cylinder to obtain the pressure distribution of the entire interference surface of the stop, and divides the interference surface of the stop into sub-regions accordingly.

[0039] S2. Calculate the dimensionless actual contact area of ​​each sub-region, and then use the normal contact pressure and the dimensionless actual contact area to calculate the normal contact force and tangential contact stiffness of each sub-region.

[0040] In practice, when calculating the contact state of each sub-region using fractal contact theory, the dimensionless actual contact area of ​​the sub-region is required as input. Numerical calculation methods are often used to solve such microscopic contact problems. This invention chooses to use the boundary element method to calculate the dimensionless actual contact area of ​​each sub-region. The boundary element method is a relatively common numerical calculation method for contact mechanics. The boundary element method has excellent computational efficiency and high computational accuracy, but it is mainly applicable to purely elastic contact problems. For the calculation of elastoplastic contact on rough surfaces, a semi-analytical algorithm based on the boundary element method is a suitable choice to balance computational efficiency and accuracy.

[0041] The semi-analytical algorithm first equates the contact problem of two elastoplastic rough surfaces to the contact problem of an elastoplastic rough surface and a rigid plane, and then performs elastoplastic calculations. The inputs of the semi-analytical algorithm include surface morphology and material parameters, and the output dimensionless actual contact area is the percentage of the contact points out of the total number of points.

[0042] Considering the multi-scale nature of the surface morphology of aero-engine rotors, this invention chooses to use fractal theory to describe the random roughness features of the sub-region surface, where the Weierstrass-Mandelbrot (WM) function can accurately describe the topographic features of the random rough surface.

[0043] Based on the above analysis, the process of calculating the dimensionless actual contact area of ​​each sub-region in this invention includes: using fractal theory to describe the random roughness characteristics of the surface of the sub-region, and obtaining the surface morphology of the sub-region, including fractal dimension and fractal roughness;

[0044] Obtain the material parameters of the sub-region, including elastic modulus, Poisson's ratio, yield strength, and tangent modulus;

[0045] By inputting the surface morphology and material parameters into a semi-analytical algorithm based on the boundary element method, the dimensionless actual contact area of ​​the sub-region is obtained.

[0046] In practice, the process of calculating the normal contact force and tangential contact stiffness of each sub-region using the normal contact pressure and the dimensionless actual contact area includes:

[0047] Construct an island distribution function using the dimensionless actual contact area of ​​the sub-region;

[0048] Hertzian contact theory was used to calculate the elastoplastic contact force and deformation of a single micro-protrusion in a sub-region. Based on the different heights of the micro-protrusions, the contact states of the micro-protrusions were classified into pure elastic deformation, elastoplastic deformation, and pure plastic deformation.

[0049] The distribution functions of micro-protrusions and islands under the same contact state are integrated simultaneously, and the integral results corresponding to micro-protrusions under different contact states are added together to obtain the normal contact force and tangential contact stiffness of the sub-region.

[0050] S3. Each sub-region is equivalent to a Jenkins element in the discrete Iwan model. The normal contact force of the sub-region is used as the normal pressure of the Jenkins element, and the tangential contact stiffness of the sub-region is used as the stiffness of the spring of the Jenkins element. The predetermined circumferential excitation displacement is input into the discrete Iwan model to obtain the tangential response force of the discrete Iwan model. The circumferential contact stiffness of the flange-stop structure is obtained by differentiating the tangential response force with respect to the circumferential excitation displacement.

[0051] In implementation, to comprehensively consider the non-uniform contact pressure distribution and surface roughness characteristics of the interface, a discrete Iwan model is chosen to calculate the torsional stiffness of the structure. In the traditional Iwan model, each Jenkins element consists of a series of linear springs and a Coulomb slider. This invention discretizes the traditional Iwan model to extend the contact model from a single sub-region to the entire mating surface. Unlike the original Iwan model, the discrete Iwan model consists of several parallel Jenkins elements, each with different stiffness and critical sliding force.

[0052] The solution provided by this invention fully considers the actual stress distribution of the flange-stop connection structure in the aero-engine rotor and the rough surface morphology of the mating interface, thus solving the problem of the difficulty in theoretically modeling the circumferential contact stiffness of the flange-stop connection structure in the aero-engine rotor.

[0053] See Figure 3 In another aspect of this invention, a device for calculating the circumferential contact stiffness of an aero-engine flange-stop structure is also provided, comprising:

[0054] The sub-region pressure distribution module 300 is used to obtain the pressure distribution of the flange end face and the pressure distribution of the stop interference surface in the aero-engine rotor. Based on the obtained pressure distribution, the flange end face and the stop interference surface are divided into multiple sub-regions, and the normal contact pressure of each sub-region is obtained.

[0055] The sub-region contact state module 310 is used to calculate the dimensionless actual contact area of ​​each sub-region, and then use the normal contact pressure and the dimensionless actual contact area to calculate the normal contact force and tangential contact stiffness of each sub-region.

[0056] The flange-stop structure contact stiffness module 320 is used to represent each sub-region as a Jenkins element in a discrete Iwan model. The normal contact force of the sub-region is used as the normal pressure of the Jenkins element, and the tangential contact stiffness of the sub-region is used as the spring stiffness of the Jenkins element. A predetermined circumferential excitation displacement is input into the discrete Iwan model to obtain the tangential response force of the discrete Iwan model. The circumferential contact stiffness of the flange-stop structure is obtained by differentiating the tangential response force with respect to the circumferential excitation displacement.

[0057] This invention also provides an electronic device, such as... Figure 4 As shown, it includes a processor 001, a communication interface 002, a memory 003, and a communication bus 004. The processor 001, communication interface 002, and memory 003 communicate with each other via the communication bus 004.

[0058] Memory 003 is used to store computer programs;

[0059] Processor 001, when executing the program stored in memory 003, implements the above-mentioned method for calculating the circumferential contact stiffness of the aero-engine flange-stop structure, including:

[0060] The pressure distribution on the flange end face and the pressure distribution on the interference surface of the engine rotor are obtained. Based on the obtained pressure distribution, the flange end face and the interference surface are divided into multiple sub-regions, and the normal contact pressure of each sub-region is obtained.

[0061] Calculate the dimensionless actual contact area of ​​each sub-region, and then use the normal contact pressure and the dimensionless actual contact area to calculate the normal contact force and tangential contact stiffness of each sub-region.

[0062] Each sub-region is equivalent to a Jenkins element in the discrete Iwan model. The normal contact force of the sub-region is used as the normal pressure of the Jenkins element, and the tangential contact stiffness of the sub-region is used as the stiffness of the spring of the Jenkins element. A predetermined circumferential excitation displacement is input into the discrete Iwan model to obtain the tangential response force of the discrete Iwan model. The circumferential contact stiffness of the flange-stop structure is obtained by differentiating the tangential response force with respect to the circumferential excitation displacement.

[0063] By applying the solution provided by this invention, the actual stress distribution of the flange-stop connection structure in the aero-engine rotor and the rough surface morphology of the mating interface are fully considered, thus solving the problem of the difficulty in theoretically modeling the circumferential contact stiffness of the flange-stop connection structure in the aero-engine rotor.

[0064] The communication bus mentioned in the above electronic devices can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. This communication bus can be divided into address bus, data bus, control bus, etc. For ease of illustration, only one thick line is used to represent it in the diagram, but this does not mean that there is only one bus or one type of bus.

[0065] The communication interface is used for communication between the aforementioned electronic devices and other devices.

[0066] The memory may include random access memory (RAM) or non-volatile memory (NVM), such as at least one disk storage device. Optionally, the memory may also be at least one storage device located remotely from the aforementioned processor.

[0067] The processors mentioned above can be general-purpose processors, including central processing units (CPUs), network processors (NPs), etc.; they can also be digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0068] In the above embodiments, implementation can be achieved entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of the present invention are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid state disk (SSD)).

[0069] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0070] The various embodiments in this specification are described in a related manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the device and electronic device embodiments are basically similar to the method embodiments, so the descriptions are relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0071] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A method for calculating the circumferential contact stiffness of an aero-engine flange-stop structure, characterized in that, include: The pressure distribution on the flange end face and the pressure distribution on the interference surface of the engine rotor are obtained. Based on the obtained pressure distribution, the flange end face and the interference surface are divided into multiple sub-regions, and the normal contact pressure of each sub-region is obtained. Calculate the dimensionless actual contact area of ​​each sub-region, and then use the normal contact pressure and the dimensionless actual contact area to calculate the normal contact force and tangential contact stiffness of each sub-region. Each sub-region is equivalent to a Jenkins element in the discrete Iwan model. The normal contact force of the sub-region is used as the normal pressure of the Jenkins element, and the tangential contact stiffness of the sub-region is used as the stiffness of the spring of the Jenkins element. A predetermined circumferential excitation displacement is input into the discrete Iwan model to obtain the tangential response force of the discrete Iwan model. The circumferential contact stiffness of the flange-stop structure is obtained by differentiating the tangential response force with respect to the circumferential excitation displacement. The process of calculating the dimensionless actual contact area of ​​each sub-region includes: Fractal theory is used to describe the random roughness characteristics of the surface of a sub-region, and the surface morphology of the sub-region, including fractal dimension and fractal roughness, is obtained. Obtain the material parameters of the sub-region, including elastic modulus, Poisson's ratio, yield strength, and tangent modulus; By inputting the surface morphology and material parameters into a semi-analytical algorithm based on the boundary element method, the dimensionless actual contact area of ​​the sub-region is obtained.

2. The method for calculating the circumferential contact stiffness of the aero-engine flange-stop structure as described in claim 1, characterized in that, The process of obtaining the pressure distribution on the flange end face includes: using the finite element analysis method to obtain the pressure distribution on the flange end face.

3. The method for calculating the circumferential contact stiffness of the aero-engine flange-stop structure as described in claim 1, characterized in that, The process of obtaining the pressure distribution of the interference surface of the stop includes: obtaining the root clearance of the stop through the finite element analysis method, and using the root clearance of the stop to obtain the pressure distribution of the interference surface of the stop based on the thick-walled cylinder theory.

4. The method for calculating the circumferential contact stiffness of the aero-engine flange-stop structure as described in claim 1, characterized in that, The process of calculating the normal contact force and tangential contact stiffness of each sub-region using normal contact pressure and dimensionless actual contact area includes: Construct an island distribution function using the dimensionless actual contact area of ​​the sub-region; Hertzian contact theory was used to calculate the elastoplastic contact force and deformation of a single micro-protrusion in a sub-region. Based on the different heights of the micro-protrusions, the contact states of the micro-protrusions were classified into pure elastic deformation, elastoplastic deformation and pure plastic deformation. The distribution functions of micro-protrusions and islands under the same contact state are integrated simultaneously, and the integral results corresponding to micro-protrusions under different contact states are added together to obtain the normal contact force and tangential contact stiffness of the sub-region.

5. The method for calculating the circumferential contact stiffness of the aero-engine flange-stop structure as described in claim 1, characterized in that, The discrete Iwan model consists of several parallel Jenkins units, each with different stiffness and critical sliding force.

6. A device for calculating the circumferential contact stiffness of an aero-engine flange-stop structure, characterized in that, include: The sub-region pressure distribution module is used to obtain the pressure distribution of the flange end face and the pressure distribution of the stop interference surface in the aero-engine rotor. Based on the obtained pressure distribution, the flange end face and the stop interference surface are divided into multiple sub-regions, and the normal contact pressure of each sub-region is obtained. The sub-region contact state module is used to calculate the dimensionless actual contact area of ​​each sub-region, and then use the normal contact pressure and the dimensionless actual contact area to calculate the normal contact force and tangential contact stiffness of each sub-region. The process of calculating the dimensionless actual contact area of ​​each sub-region includes: Fractal theory is used to describe the random roughness characteristics of the surface of a sub-region, and the surface morphology of the sub-region, including fractal dimension and fractal roughness, is obtained. Obtain the material parameters of the sub-region, including elastic modulus, Poisson's ratio, yield strength, and tangent modulus; The surface morphology and material parameters are input into a semi-analytical algorithm based on the boundary element method to obtain the dimensionless actual contact area of ​​the sub-region; The flange-stop structure contact stiffness module is used to represent each sub-region as an equivalent Jenkins element in a discrete Iwan model. The normal contact force of the sub-region is used as the normal pressure of the Jenkins element, and the tangential contact stiffness of the sub-region is used as the spring stiffness of the Jenkins element. A predetermined circumferential excitation displacement is input into the discrete Iwan model to obtain the tangential response force of the discrete Iwan model. The circumferential contact stiffness of the flange-stop structure is obtained by differentiating the tangential response force with respect to the circumferential excitation displacement.

7. An electronic device, characterized in that, It includes a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; Memory is used to store processor-executable instructions; A processor, when executing instructions stored in memory, implements the steps of the method described in any one of claims 1-5.

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