Aero-engine disc drum bolted joint structure parameter optimization method based on digital twinning

Abstract

The present application relates to the technical field of aero-engine bolt optimization, in particular to a parameter optimization method for a disc-drum bolt connection structure of a digital twin aero-engine, comprising the following steps: S1, systematically modeling from the dimensions of geometry, physics, behavior and rules, and constructing a digital twin of the disc-drum bolt connection structure; S2, establishing a geometric model of the disc-drum bolt connection structure of the aero-engine, wherein the geometric model describes the geometric parameters of size and shape and assembly relationship. The present application establishes geometric, physical, behavioral and rule models, constitutes a digital twin of the disc-drum bolt connection structure, comprehensively considers the influence of each parameter of the disc-drum bolt connection structure on the connection performance, obtains the optimal parameter combination with the maximum connection stiffness, and the optimization result is accurate and reliable, which can provide a reference for the optimization design of the connection performance of the disc-drum bolt connection structure.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of aero-engine bolt optimization, and particularly relates to a parameter optimization method for a bolt connection structure of a digital twin aero-engine disk drum. BACKGROUND

[0002] Bolt connection is widely used in aero-engine structures due to its advantages such as convenient assembly and disassembly, flexible design, etc. With the continuous development of aero-engine technology, the requirements for bolt connection performance and stability are becoming higher and higher. Although the proportion of bolt connection in the whole structure is not high, it is crucial to the reliability of the whole structure. In the face of the challenges of engine modification and replacement, traditional design methods cannot meet the needs of modern high-performance engine bolt connection structures, and more efficient and accurate design and optimization methods for bolt connection need to be researched and established. The optimization design of aero-engine bolt connection structure involves multi-disciplinary and multi-objective problems, and multiple factors need to be considered comprehensively. At the same time, there may be mutual constraints between these factors, and multi-objective optimization must be performed during the design process to maximize the overall performance. However, traditional simulation analysis methods often use empirical models or simplified structural models as the basis, which cannot fully reflect the real characteristics of complex systems, and the design decisions obtained may cause significant differences between virtual products and actual products. Moreover, traditional design methods rely heavily on experience and trial-and-error methods, which often require a large amount of time and computational resources, and have problems such as low design efficiency, high cost, and imperfect auxiliary decision-making functions. SUMMARY

[0003] The purpose of the present application is to solve the problems existing in the prior art, and a parameter optimization method for a bolt connection structure of a digital twin aero-engine disk drum is proposed.

[0004] In order to achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0005] The parameter optimization method for the bolt connection structure of the digital twin aero-engine disk drum comprises the following steps:

[0006] S1, systematically modeling from the geometric, physical, behavioral, and rule dimensions to construct a digital twin of the disk drum bolt connection structure;

[0007] S2, describing the geometric parameters of size and shape, assembly relationship in the geometric model, and establishing a geometric model of the aero-engine disk drum bolt connection structure;

[0008] S3, analyzing the physical characteristics of structure stress, fatigue, and strain in the physical model, and further introducing related information of constraints on the basis of the geometric model, using commercial software Workbench 2023R1 to establish a finite element model of the disk drum bolt connection structure, and solving the physical properties of the model;

[0009] S4, the behavior model describes the external environment and interference of the physical entity at different granularities and different spatial scales, and the response and behavior triggered under the action of the internal operating mechanism, the contact stiffness is characterized by the thin layer unit method, the behavior model is established, and the mapping of the physical entity is truly realized;

[0010] S5, the rule model models the law or rule of the operation of the physical entity, including the law and rule related to historical data, the experience summarized from knowledge, etc., so that the digital twin has multiple functions such as prediction, evaluation, assessment and optimization, thereby guiding the physical space, determining the main structural parameters affecting the performance of the disc-drum bolt connection and the value range thereof, and based on the adaptive genetic algorithm of population dissimilarity, and coding transformation, an initial population is generated, and a rule model is established;

[0011] S6, a hierarchical structure model is established, the comprehensive optimization problem is divided into sub-targets, the weight of an element at a certain layer to an element at an upper layer is calculated by solving the characteristic vector of the judgment matrix, and finally the weight of the comprehensive optimization of the total target is obtained by weighting and summing;

[0012] S7, according to the disc-drum bolt connection structure digital twin, combined with the parameter weight obtained by the analytic hierarchy process, the bolt connection structure is comprehensively optimized, and the optimal parameter combination scheme is obtained.

[0013] Compared with the prior art, the geometry, physics, behavior and rule models are established, the disc-drum bolt connection structure digital twin is constituted, the influence of each parameter of the disc-drum bolt connection structure on the connection performance is comprehensively considered, the optimal parameter combination with the maximum connection stiffness is obtained, the optimization result is accurate and reliable, and the optimization result can provide a reference basis for the optimization design of the connection performance of the disc-drum bolt connection structure;

[0014] A geometry model of an aero-engine disc-drum bolt connection structure is established, a finite element model of the disc-drum bolt connection structure is established by using a commercial software Workbench2023R1, and the physical properties of the model are solved; the behavior model is established by using the thin layer unit method to characterize the contact stiffness, and the mapping of the physical entity is truly realized; the main structural parameters affecting the performance of the disc-drum bolt connection and the value range thereof are determined, and coding transformation is performed to obtain a test factor level coding table, an initial population is generated, adaptive crossover and mutation operations are performed according to the population dissimilarity to establish a rule model, so that the digital twin has an optimization function; finally, the minimum equivalent stress, the lightest structure mass and the maximum connection stiffness are taken as the optimization objectives, the digital twin is established, and the multi-objective structure optimization is performed by using the analytic hierarchy process.

[0015] Preferably, the disc-drum bolt connection structure parameters to be optimized include the installation edge thickness, the number of bolts, the installation edge height and the bolt pre-tightening force.

[0016] Further, the disc drum bolt connection structure parameters are accurately acquired to understand the disc drum bolt connection condition.

[0017] Preferably, the disc drum bolt connection structure geometric model is established according to the actual size of the aero-engine rotor; the Workbench 2023R1 software is utilized to perform meshing on the geometric model, the boundary condition and contact solution are set, the physical model is obtained; the thin layer element method is utilized to characterize the contact stiffness, the behavior model is established, the mapping to the physical entity is truly reflected, the contact stiffness on each grid node is calculated according to the size of the contact stress, and then the elastic modulus of the thin layer element is calculated through the average value of the contact stiffness on each grid node through the following formula, and then the complete model of the bolt connection structure using the thin layer element method is obtained.

[0018]

[0019] k=0.9933p 0.6736

[0020] The adaptive genetic algorithm based on population dissimilarity is utilized to establish the rule model; and the disc drum bolt connection structure digital twin is established.

[0021] Further, the rule model is fully established to effectively realize the establishment of the disc drum bolt connection structure digital twin, so as to optimize the aero-engine disc drum bolt connection parameters through the digital twin model.

[0022] Preferably, the adaptive genetic algorithm based on population dissimilarity in S5 adjusts the crossover and mutation probability through the population dissimilarity, and the dissimilarity between individuals and the overall dissimilarity of the population are expressed through the following formula:

[0023]

[0024] Wherein, d i，j represents the dissimilarity of individual x i and x j , x ik and x jk are the kth gene of individual x i and x j .

[0025] Further, the difference between the individual condition and the overall condition is understood under the condition of the adaptive genetic algorithm based on population dissimilarity.

[0026] The beneficial effects of the present application are:

[0027] 1. By establishing geometric, physical, behavioral, and rule models, a digital twin of the disc bolt connection structure was constructed. The influence of various parameters of the disc bolt connection structure on its connection performance was comprehensively considered, and the optimal parameter combination with the maximum connection stiffness was obtained. The optimization results are accurate and reliable, and can provide a reference for the optimization design of the connection performance of the disc bolt connection structure.

[0028] 2. By establishing a geometric model of the disc-drum bolt connection structure of an aero-engine, a finite element model of the disc-drum bolt connection structure was built using the commercial software Workbench 2023 R1, and the physical properties of the model were solved. The contact stiffness was characterized using the thin-layer element method, and a behavioral model was established to realistically reflect the mapping to the physical entity. The main structural parameters affecting the performance of the disc-drum bolt connection and their value ranges were determined, and coded transformations were performed to obtain an experimental factor level coding table. An initial population was generated, and a rule model was established based on the population dissimilarity, adaptive crossover, and mutation operations to enable the digital twin to have optimization functions. Finally, with the optimization objectives of minimizing equivalent stress, lightest structural mass, and maximum connection stiffness, a digital twin was established, and multi-objective structural optimization was performed using the analytic hierarchy process (AHP). Attached Figure Description

[0029] Figure 1 This is a flowchart of the present invention;

[0030] Figure 2 This is a schematic diagram of the digital twin of the disc-drum bolt connection structure of the present invention;

[0031] Figure 3 This is the geometric model of the disc-drum bolt connection structure of the present invention;

[0032] Figure 4 This is the physical model of the disc-drum bolt connection structure of the present invention;

[0033] Figure 5 This is the hierarchical structure model of the present invention;

[0034] Figure 6 This is a flowchart illustrating the optimization of the disc-drum bolt connection structure of the present invention. Detailed Implementation

[0035] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0036] A method for optimizing the structural parameters of the bolted connection structure of an aero-engine based on digital twins, such as... Figure 1 As shown, it includes the following steps:

[0037] S1, from the geometric, physical, behavior, rule dimension, the digital twin of the disc drum bolt connection structure is constructed;

[0038] S2, the geometric model describes the geometric parameters of size shape and assembly relationship, the geometric model of the disc drum bolt connection structure of the aero-engine is established, which contains the geometric parameters of size shape and assembly relationship of the research object such as Figure 3 As shown in the table 1, in the application, the disc drum bolt connection structure parameters are shown in the table 1;

[0039] Table 1 disc drum bolt connection structure geometric attribute

[0040] Item Size / Quantity Single-sided drum length (mm) 40 Center circle diameter (mm) 279 Drum inner diameter (mm) 327 Drum outer diameter (mm) 332 Drum thickness (mm) 2.5 Wheel disc thickness (mm) 10 Mounting edge thickness (mm) 6 Total height (mm) 21.8 Number of bolts 48 Bolt model M8

[0041] S3, the finite element model of the disc drum bolt connection structure is established by using the commercial software Workbench 2023R1, the circumferential cyclic symmetry is set for the model, the whole calculation is realized, the boundary conditions are set, the materials of the drum cylinder and the wheel disc are 45 steel, the material of the bolt is GH4169, the material characteristic parameters are shown in the table 2, and the physical properties of the model are solved;

[0042] Table 2 material characteristic parameters

[0043]

[0044] S4, the contact stiffness is characterized by using the thin layer element method, the behavior model is established, the mapping of the physical entity is truly reflected, the contact stiffness on each grid node is calculated according to the size of the contact stress, and then the elastic modulus of the thin layer element is calculated by the average value of the contact stiffness on each grid node through the following formula, and then the complete model of the bolt connection structure using the thin layer element method is obtained;

[0045]

[0046] k=0.9933p 0.6736

[0047] S5, the main structure parameters affecting the performance of the disc drum bolt connection and the value range thereof are determined, and coding transformation is carried out to generate an initial population, and a rule model is established; the optimization parameters include the installation edge thickness, the number of bolts, the installation edge height and the bolt pre-tightening force;

[0048] In the application, the installation edge structure parameters are selected as the installation edge thickness, the number of bolts, the installation edge height and the bolt pre-tightening force, and their change ranges are shown in the table 3;

[0049] Table 3 change range of optimization parameters

[0050]

[0051] A new population is generated by adaptive crossover and mutation, the crossover and mutation probability is changed by population diversity, the fitness value of individual is calculated, and the population diversity is calculated according to the following formula:

[0052]

[0053] Wherein, d i，j represents the diversity of individual x i and x j , x ik and x jk are the kth gene of individual x i and x j ;

[0054] S6, a hierarchical structure model is established, the comprehensive optimization problem is divided into sub-targets, the weight of an element at a certain layer to an element at an upper layer is calculated by solving the characteristic vector of a judgment matrix, and finally the weight of the comprehensive optimization of the total target is obtained by weighting and summing;

[0055] S7, according to the parameter weight obtained by the analytic hierarchy process, the digital twin of the disc-drum bolt connection structure is combined to comprehensively optimize the bolt connection structure and obtain the optimal parameter combination scheme; the optimal parameter combination scheme, the digital twin composition and the optimization process are shown in Figure 6 ; wherein Figure 4 , (a) is a grid diagram of the disc-drum bolt connection structure, (b) is a schematic diagram of the boundary conditions of the disc-drum bolt connection structure, and (c) is a stress diagram of the disc-drum bolt connection structure.

[0056] In this embodiment, the optimal scheme finally obtained is that the installation edge thickness is 6mm, the number of bolts is 44, the installation edge height is 10mm, and the bolt pre-tightening force is 9000N. The initial model bolt connection stiffness is 258.52x10 7 N / m, the equivalent stress is 3369.03MPa, the structure mass is 201.90kg, the installation edge structure under the optimal parameter combination is improved by 74.21% in connection stiffness, reduced by 115.67% in equivalent stress, and reduced by 7.25% in structure mass. According to the analytic hierarchy process, the weight of the disc-drum bolt connection structure parameters to the comprehensive optimization of the total target is w=[0.4737, 0.3233, 0.2030].

[0057] The above is only the preferred specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can make equivalent replacement or change according to the technical solution and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A method for optimizing the structural parameters of bolted connections on aero-engine discs based on digital twins, characterized in that: Includes the following steps: S1. Systematically model the structure from geometric, physical, behavioral, and rule dimensions to construct a digital twin of the disc drum bolt connection structure; S2. Geometric model describes the geometric parameters of size, shape, and assembly relationship, and establishes the geometric model of the disc drum bolt connection structure of the aero-engine; S3. The physical model analyzes the physical characteristics of structural stress, fatigue, and strain. Based on the geometric model, relevant constraint information is further introduced. The finite element model of the disc bolt connection structure is established using the commercial software Workbench 2023R1, and the physical properties of the model are solved. S4. The behavior model describes the external environment and disturbances of physical entities at different granularities and spatial scales, as well as the responses and behaviors caused by the internal operating mechanisms. The thin-layer element method is used to characterize the contact stiffness and establish a behavior model to truly reflect the mapping of the physical entity. S5. The rule model models the laws or rules of physical entity operation, including laws and rules related to historical data and experience summarized from knowledge, so that the digital twin has multiple functions such as prediction, evaluation, assessment and optimization, thereby guiding the physical space, determining the main structural parameters affecting the performance of disc drum bolt connection and their value range, and using an adaptive genetic algorithm based on population dissimilarity, and performing encoding transformation to generate an initial population and establish a rule model. S6. Establish a hierarchical structure model, break down the comprehensive optimization problem into sub-objectives, calculate the weight of a certain layer element to the upper layer element by solving the eigenvector of the judgment matrix, and finally perform a weighted sum to obtain the weight of the comprehensive optimization of the overall objective. S7. Based on the digital twin of the disc-drum bolt connection structure and the parameter weights obtained by the analytic hierarchy process, the bolt connection structure is comprehensively optimized to obtain the optimal parameter combination scheme.

2. The method for optimizing the structural parameters of the disc-drum bolt connection structure of an aero-engine based on digital twins according to claim 1, characterized in that: The structural parameters of the disc-drum bolt connection to be optimized include the mounting edge thickness, the number of bolts, the mounting edge height, and the bolt preload.

3. The method for optimizing the structural parameters of the disc-drum bolt connection structure of an aero-engine based on digital twins according to claim 1, characterized in that: A geometric model of the disc-drum bolted connection structure was established based on the actual dimensions of the aircraft engine rotor. The geometric model was meshed using Workbench 2023 R1 software, boundary conditions were set, and contact solutions were obtained to obtain the physical model. The contact stiffness was characterized using the thin-layer element method, and a behavioral model was established to realistically reflect the mapping of the physical entity. The contact stiffness on each mesh node was calculated according to the magnitude of the contact stress. The elastic modulus of the thin-layer element was then calculated from the average value of the contact stiffness on each mesh node using the following formula, thus obtaining a complete model of the bolted connection structure using the thin-layer element method. ； An adaptive genetic algorithm based on population dissimilarity was used to establish a rule model; a digital twin of the disc drum bolt connection structure was established.

4. The method for optimizing the structural parameters of the disc-drum bolt connection structure of an aero-engine based on digital twins according to claim 1, characterized in that: The S5 adaptive genetic algorithm based on population dissimilarity adaptively adjusts the crossover and mutation probabilities through population dissimilarity. The dissimilarity between individuals and the overall dissimilarity of the population are expressed by the following formula: ； ； ； in, d i，j Represents an individual x i and x j Dissimilarity x ik , x jk Individuals x i and x j The k One gene.

Images