Disc feature mockup design method based on additive manufacturing concept

Abstract

The application discloses a wheel disc feature structure simulation part design method based on an additive manufacturing idea, and comprises the following steps: firstly, a parameterized model of a wheel disc is established, and stress field data of the wheel disc feature structure is obtained by using finite element analysis means; then, based on the stress field data of the wheel disc feature structure, a MATLAB program is written to obtain a stress gradient space curve; finally, initial cross-sectional dimensions of the simulation part are determined based on test conditions of a testing machine, and a size iteration formula is determined based on the additive manufacturing idea, so that the contour curve of the simulation part is iteratively calculated according to the stress gradient space curve, and the simulation part configuration is determined in combination with the test conditions of the testing machine; compared with the prior art, the method does not need to select a stress gradient path, design an initial configuration of the simulation part and optimize the size of the initial configuration in the whole design process, greatly improves the standardization and normalization of the wheel disc feature structure simulation part design, fundamentally avoids repeated design processes, shortens a design period and improves design efficiency.

Description

Technical Field

[0001] This invention relates to the field of aero-engine technology, and in particular, to a design method for a simulated disk feature structure based on additive manufacturing principles. Background Technology

[0002] In the design of aero-engine disk feature structures, to evaluate the fatigue life of the aero-engine disk feature structures under service conditions, prediction is usually made by real component tests or simulated component tests. Although simulated component tests are inferior to real component tests in terms of life prediction accuracy, they can greatly reduce costs, save resources, shorten the cycle, and significantly reduce design verification costs. This is more conducive to the rapid engineering application of aero-engine disk feature structures, thereby facilitating the iterative optimization of aero-engine disk feature structures and meeting the increasingly higher performance requirements of aero-engines.

[0003] Currently, the design approach for simulation components is shifting from ensuring consistent damage parameters at critical points to ensuring consistent damage parameter distribution across critical areas. Given the highly complex configuration and stress distribution of aero-engine rotor discs, achieving consistent damage parameter distribution across critical areas is practically impossible. Therefore, designers typically employ a simplified approach, designing the initial configuration of the simulation component by ensuring similar pressure distribution along a certain path between the simulation component and the real component. Consequently, the selection of the stress gradient path direction significantly impacts the effectiveness of the simulation component design and the prediction accuracy of simulation tests. However, the selection of the stress gradient path direction and the determination of the initial configuration of the simulation component heavily rely on the designer's experience, lacking a unified standard. This leads to repeated iterations in the simulation component design process, affecting design efficiency. Furthermore, after obtaining the initial configuration of the simulation component, finite element method is required for dimensional optimization to obtain the final configuration. However, dimensional optimization is time-consuming, resulting in low design efficiency for the simulation component. Summary of the Invention

[0004] This invention provides a design method for a simulating wheel feature structure based on additive manufacturing, which solves the technical problems of existing simulating component design, which requires stress gradient path selection, initial configuration design, and initial configuration size optimization, resulting in a design process that is prone to repetition, long design cycle, and low design efficiency.

[0005] According to one aspect of the present invention, a design method for a simulated component of a wheel feature structure based on additive manufacturing is provided, comprising the following steps: S1: establishing a parametric model of the wheel and obtaining stress field data of the wheel feature structure using finite element analysis; S2: based on the stress field data of the wheel feature structure, writing a MATLAB program to obtain the stress gradient space curve; S3: determining the initial cross-sectional dimensions of the simulated component based on the test conditions of the testing machine, determining the dimension iteration formula based on the additive manufacturing concept, iteratively calculating the contour curve of the simulated component according to the stress gradient space curve, and determining the configuration of the simulated component in combination with the test conditions of the testing machine.

[0006] As a further improvement to the above technical solution:

[0007] Further, step S2 specifically includes the following steps: S21: Based on the stress field data of the roulette wheel's characteristic structure, establish an xyz coordinate system, extract the position coordinates (x, y, z) of the finite element model nodes, and the stress values ​​in the x, y, z, xy, xz, and yz directions; S22: Use the moving least squares method to establish an influence radius centered on the finite element model nodes, and construct a quadratic stress field function within the influence domain; S23: Calculate the Hessian matrix of the stress field using the weighted least squares method, perform eigenvalue decomposition on the Hessian matrix to obtain the direction of maximum curvature, and form a stress gradient space curve according to a set step size.

[0008] Furthermore, between steps S21 and S22, there is also the step of removing edge finite element model nodes and performing Kriging interpolation on the missing data.

[0009] Furthermore, the secondary stress field function is as follows:

[0010] ;

[0011] In the formula, x is the x-coordinate of the finite element model node in the xyz coordinate system, y is the y-coordinate of the finite element model node in the xyz coordinate system, z is the z-coordinate of the finite element model node in the xyz coordinate system, σ(x,y,z) is the stress of the finite element model node, and a0, a1, a2, a3, a4, a5, a6...a n-2 a n-1 a n For the corresponding coefficients.

[0012] Furthermore, the Hessian matrix is ​​as follows:

[0013] ;

[0014] In the matrix, The sign of the partial derivative. This is a second-order stress field function.

[0015] Furthermore, the eigenvalue decomposition of the Hessian matrix to obtain the direction of maximum curvature specifically includes the following steps:

[0016] The Hessian matrix is ​​orthogonally diagonalized using the following formula:

[0017] ;

[0018] In the formula, Q is an orthogonal matrix, Ʌ is a diagonal matrix, and T is the matrix transpose symbol;

[0019] Solve for the characteristic equation, which is as follows:

[0020] ;

[0021] In the formula, λ is the eigenvalue, and v is the unit eigenvector corresponding to λ;

[0022] Find the largest λ among the eigenvalues max and the corresponding unit eigenvector v max v max This is the direction of maximum curvature.

[0023] Furthermore, the size iteration formula is as follows:

[0024] ;

[0025] In the formula, ΔL denoted as step size, σ yield is the material yield strength, tn is the current cross-sectional size, tn+1 is the cross-sectional size of the next iteration step, and ∇σn is the design stress gradient.

[0026] Furthermore, the simulation component includes a clamping section and a test section, with the length of the clamping section being ≥ 5 times the maximum cross-sectional height difference of the test section.

[0027] Furthermore, step S3 is followed by the step of smoothing the sharp corners of the simulated part configuration.

[0028] Further, step S1 specifically includes the following steps: establishing a parameterized model of the wheel disk through finite element analysis, setting parameters according to the actual material parameters, using a denser mesh in the characteristic structure region and a sparser mesh in the non-characteristic structure region, while ensuring that the size ratio of adjacent elements is ≤1:3; applying centrifugal load, temperature field and contact friction coefficient to calculate the displacement of the wheel disk; extracting the displacement results of the characteristic structure as the displacement boundary conditions of the sub-model, and refining the mesh of the sub-model to obtain high-resolution stress field data of the characteristic parts of the wheel disk.

[0029] The present invention has the following beneficial effects:

[0030] This invention discloses a design method for a simulated wheel feature structure based on additive manufacturing principles. First, a parametric model of the wheel is established, and stress field data of the wheel's feature structure is obtained using finite element analysis. Then, based on the stress field data, a MATLAB program is written to calculate the stress gradient space curve. Finally, the initial cross-sectional dimensions of the simulated component are determined based on the testing conditions of the testing machine. An iterative dimensional formula is determined based on additive manufacturing principles to iteratively calculate the contour curve of the simulated component according to the stress gradient space curve. The configuration of the simulated component is then determined in conjunction with the testing conditions of the testing machine. This scheme, based on additive manufacturing principles, utilizes iterative dimensional formulas and stress gradient space curves... The method allows for the rapid design of a simulated configuration of a wheel-shaped feature structure based on initial cross-sectional dimensions. By utilizing stress gradient space curves, the simulated configuration accurately reflects the three-dimensional stress field of the real component, enabling accurate fatigue analysis and fracture prediction. This facilitates the engineering application and iterative optimization of wheel-shaped feature structures. Compared to existing technologies, the entire design process eliminates the need for stress gradient path selection, initial configuration design, and initial configuration dimensional optimization. This significantly improves the standardization and normalization of wheel-shaped feature structure simulation design, fundamentally avoiding repetitive design processes, shortening the design cycle, and increasing design efficiency. It is highly practical and suitable for widespread promotion and application.

[0031] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0032] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0033] Figure 1 This is a flowchart illustrating the steps of a preferred embodiment of the design method for a simulated wheel feature structure based on additive manufacturing principles.

[0034] Figure 2 This is a Matlab stress point cloud diagram of the wheel feature structure in the wheel feature structure simulation part design method based on additive manufacturing concept in a preferred embodiment of the present invention;

[0035] Figure 3 This is a schematic diagram of the stress gradient space curve in the xyz coordinate system in the design method of the wheel feature structure simulation part based on the additive manufacturing concept of the preferred embodiment of the present invention;

[0036] Figure 4 This is a schematic diagram of the contour curve of the simulated part in the design method of the simulated part of the wheel feature structure based on the additive manufacturing concept of the preferred embodiment of the present invention;

[0037] Figure 5 This is a schematic diagram of the simulated component configuration in the wheel feature structure simulation component design method based on additive manufacturing concept in a preferred embodiment of the present invention. Detailed Implementation

[0038] The following description provides specific application scenarios and requirements for this specification, intended to enable those skilled in the art to make and use the contents of this specification. Various partial modifications to the disclosed embodiments will be apparent to those skilled in the art, and the general principles defined herein can be applied to other embodiments and applications without departing from the spirit and scope of this specification.

[0039] The terminology used herein is for the purpose of describing particular exemplary embodiments only and is not restrictive. For example, unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “the” as used herein may also include the plural forms. When used in this specification, the terms “comprising,” “including,” and / or “containing” mean that the associated integers, steps, operations, elements, and / or components are present, but do not preclude the presence of one or more other features, integers, steps, operations, elements, components, and / or groups, or that other features, integers, steps, operations, elements, components, and / or groups may be added to the system / method.

[0040] Considering the following description, these and other features of this specification, as well as the operation and function of the related components of the structure, and the economy of assembly and manufacture of the parts, can be significantly improved. All of these form part of this specification with reference to the accompanying drawings. However, it should be clearly understood that the drawings are for illustrative and descriptive purposes only and are not intended to limit the scope of this specification. It should also be understood that the drawings are not drawn to scale.

[0041] like Figure 1 As shown, the design method for a simulated wheel feature structure based on additive manufacturing in this embodiment includes the following steps: S1: Establish a parametric model of the wheel and obtain stress field data of the wheel feature structure using finite element analysis; S2: Based on the stress field data of the wheel feature structure, write a MATLAB program to obtain the stress gradient space curve; S3: Determine the initial cross-sectional dimensions of the simulated part based on the test conditions of the testing machine, determine the dimension iteration formula based on the additive manufacturing concept, iteratively calculate the contour curve of the simulated part according to the stress gradient space curve, and determine the configuration of the simulated part in combination with the test conditions of the testing machine.

[0042] like Figure 4As shown, specifically, the design method for a simulated wheel feature structure based on additive manufacturing principles of this invention first establishes a parametric model of the wheel and uses finite element analysis to obtain stress field data of the wheel's feature structure. Then, based on the stress field data of the wheel's feature structure, a MATLAB program is written to calculate the stress gradient space curve. Finally, based on the test conditions of the testing machine, the initial cross-sectional dimensions of the simulated component are determined, and a dimension iteration formula is determined based on additive manufacturing principles. The contour curve of the simulated component is then iteratively calculated based on the stress gradient space curve, and the configuration of the simulated component is determined in conjunction with the test conditions of the testing machine. This scheme, based on additive manufacturing principles, utilizes dimension iteration formulas and stress gradient... The simulation configuration of the roulette wheel feature structure can be quickly designed using spatial curves and initial cross-sectional dimensions. The stress gradient spatial curves enable the simulation configuration to accurately reflect the three-dimensional stress field of the real component, thus allowing for accurate fatigue analysis and fracture prediction. This is beneficial for the engineering application and iterative optimization of the roulette wheel feature structure. Compared with existing technologies, the entire design process does not require the selection of stress gradient paths, the design of the initial configuration of the simulation component, or the optimization of the initial configuration dimensions. This greatly improves the standardization and normalization of the design of the roulette wheel feature structure simulation component, fundamentally avoids repeated design processes, shortens the design cycle, improves design efficiency, and is highly practical and suitable for widespread promotion and application.

[0043] It should be understood that the wheel's characteristic structure includes a boss, an eccentric hole, or a tenon.

[0044] Optionally, in one embodiment, the wheel's characteristic structure is an eccentric hole, the wheel material is GH4169, and the operating speed is 21945 r / min. Its Matlab stress point cloud diagram is shown below. Figure 2 As shown.

[0045] like Figure 3As shown, in this embodiment, step S2 specifically includes the following steps: S21: Based on the stress field data of the roulette wheel feature structure, establish an xyz coordinate system, extract the position coordinates (x, y, z) of the finite element model nodes, and the stress values ​​in the x, y, z, xy, xz, and yz directions; S22: Use the moving least squares method to establish an influence radius centered on the finite element model nodes, and construct a quadratic stress field function within the influence domain; S23: Calculate the Hessian matrix of the stress field using the weighted least squares method, perform eigenvalue decomposition on the Hessian matrix to obtain the direction of maximum curvature, and form a stress gradient space curve according to a set step size. Specifically, this scheme uses a three-dimensional stress gradient similarity target, based on the stress field data of the roulette wheel feature structure, to construct a quadratic stress field function of the roulette wheel feature structure, obtain the direction of maximum curvature through eigenvalue decomposition, and form a stress gradient space curve according to a set step size. In stress gradient path analysis, it comprehensively considers the distribution of the entire stress field and has a more rigorous mathematical derivation, enabling more accurate fatigue analysis and fracture prediction, and more accurately reflecting the actual situation of real components.

[0046] In this embodiment, the step between steps S21 and S22 further includes: removing edge finite element model nodes and performing Kriging interpolation on the missing data. Specifically, removing edge finite element model nodes effectively narrows the interpolation range and reduces computational costs, while performing Kriging interpolation on the missing data ensures the accurate continuity of the subsequently constructed secondary stress field function.

[0047] It should be understood that, in one embodiment, the wheel structure features an eccentric hole, and the edge finite element model node refers to the finite element model node that is less than 0.1 mm from the surface.

[0048] In this embodiment, the secondary stress field function is as follows:

[0049] ;

[0050] In the formula, x is the x-coordinate of the finite element model node in the xyz coordinate system, y is the y-coordinate of the finite element model node in the xyz coordinate system, z is the z-coordinate of the finite element model node in the xyz coordinate system, σ(x,y,z) is the stress of the finite element model node, and a0, a1, a2, a3, a4, a5, a6...a n-2 a n-1 a n For the corresponding coefficients.

[0051] Specifically, the accuracy of the obtained stress gradient space curve is ensured by using the aforementioned quadratic stress field function.

[0052] In this embodiment, the Hessian matrix is ​​as follows:

[0053] ;

[0054] In the matrix, The sign of the partial derivative. This is a second-order stress field function.

[0055] Specifically, the above matrix ensures the accuracy of the obtained stress gradient space curve.

[0056] In this embodiment, the eigenvalue decomposition of the Hessian matrix to obtain the direction of maximum curvature specifically includes the following steps:

[0057] The Hessian matrix is ​​orthogonally diagonalized using the following formula:

[0058] ;

[0059] In the formula, Q is an orthogonal matrix, Ʌ is a diagonal matrix, and T is the matrix transpose symbol;

[0060] Solve for the characteristic equation, which is as follows:

[0061] ;

[0062] In the formula, λ is the eigenvalue, and v is the unit eigenvector corresponding to λ;

[0063] Find the largest λ among the eigenvalues max and the corresponding unit eigenvector v max v max This is the direction of maximum curvature.

[0064] Specifically, through the above steps, the direction of maximum curvature is accurately derived, ensuring the accuracy of the obtained stress gradient space curve.

[0065] In this embodiment, the size iteration formula is as follows:

[0066] ;

[0067] In the formula, ΔL denoted as step size, σ yield is the material yield strength, tn is the current cross-sectional size, tn+1 is the cross-sectional size of the next iteration step, and ∇σn is the design stress gradient.

[0068] Specifically, by using the above-mentioned dimensional iteration formula, and in conjunction with the stress gradient space curve, the cross-sectional dimensions are calculated layer by layer to complete the forward design of the stress gradient of the real component and the configuration of the simulated component.

[0069] In this embodiment, the simulated component includes a clamping section and a test section, with the length of the clamping section being ≥5 times the maximum cross-sectional height difference of the test section. Specifically, by ensuring that the length of the clamping section is ≥5 times the maximum cross-sectional height difference, the influence of the clamping section on the test section is reduced or even eliminated to the maximum extent possible, thereby improving the accuracy of fatigue analysis and fracture prediction results.

[0070] like Figure 5 As shown, optionally, in one embodiment, the clamping segment has a length of 45mm, a width of 40mm, a thickness of 8mm, and a maximum cross-sectional height difference of 9mm.

[0071] like Figure 5 As shown, in this embodiment, after step S3, the method further includes a step of smoothing the sharp corners of the simulated component configuration. Specifically, the smoothing process avoids stress concentration at the sharp corners, thus reflecting the actual situation of the real component.

[0072] like Figure 5 As shown, optionally, a chamfer is used for smoothing, where R1 is the chamfer angle.

[0073] In this embodiment, step S1 specifically includes the following steps: A parameterized model of the wheel is established through finite element analysis, set according to actual material parameters, using a denser mesh in the characteristic structure region and a sparser mesh in the non-characteristic structure region, while ensuring that the size ratio of adjacent elements is ≤1:3; centrifugal load, temperature field, and contact friction coefficient are applied to calculate the displacement of the wheel; the displacement results of the characteristic structure are extracted as the displacement boundary conditions of the sub-model, and the sub-model mesh is refined to obtain high-resolution stress field data of the characteristic parts of the wheel. Specifically, through the above steps, high-resolution stress field data of the characteristic parts of the wheel is obtained to ensure the accuracy of the subsequently obtained stress gradient space curve.

[0074] It should be understood that the centrifugal load and temperature field are the centrifugal load and temperature field under the actual service environment of the component.

[0075] Alternatively, the finite element analysis software can be ANSYS – Mechanical or ABAQUS.

[0076] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects.

[0077] In summary, after reading the detailed disclosure of this specification, those skilled in the art will understand that the foregoing detailed disclosure is presented by way of example only and is not restrictive. Although not explicitly stated herein, those skilled in the art will understand that this specification requires various reasonable changes, improvements, and modifications to the embodiments. These changes, improvements, and modifications are intended to be made by this specification and are within the spirit and scope of the exemplary embodiments described herein.

[0078] Furthermore, certain terms in this specification have been used to describe embodiments of this specification. For example, "an embodiment," "an embodiment," and / or "some embodiments" mean that a particular feature, structure, or characteristic described in connection with that embodiment may be included in at least one embodiment of this specification. Therefore, it is to be emphasized and understood that two or more references to "an embodiment" or "an embodiment" or "alternative embodiment" in various parts of this specification do not necessarily refer to the same embodiment. Moreover, specific features, structures, or characteristics may be suitably combined in one or more embodiments of this specification.

[0079] It should be understood that in the foregoing description of the embodiments in this specification, various features are combined in a single embodiment, drawing, or description for the purpose of simplifying the description and aiding in the understanding of a feature. However, this does not mean that the combination of these features is necessary, and those skilled in the art may readily identify some of the devices as separate embodiments when reading this specification. That is, the embodiments in this specification can also be understood as an integration of multiple secondary embodiments. It is also valid when each secondary embodiment contains fewer than all the features of a single foregoing disclosed embodiment.

[0080] Finally, it should be understood that the embodiments disclosed herein are illustrative of the principles of the embodiments described in this specification. Other modified embodiments are also within the scope of this specification. Therefore, the embodiments disclosed in this specification are merely examples and not limitations. Those skilled in the art can implement the applications described in this specification using alternative configurations based on the embodiments in this specification. Therefore, the embodiments in this specification are not limited to the embodiments precisely described in the applications.

Claims

1. A design method for a simulated feature structure of a wheel based on additive manufacturing principles, characterized in that, Includes the following steps: S1: Establish a parametric model of the roulette wheel and use finite element analysis to obtain stress field data of the characteristic structure of the roulette wheel; S2: Based on the stress field data of the characteristic structure of the wheel disk, write a MATLAB program to obtain the stress gradient space curve; S3: Determine the initial cross-sectional dimensions of the simulated part based on the test conditions of the testing machine, determine the dimension iteration formula based on the additive manufacturing concept, calculate the contour curve of the simulated part iteratively based on the stress gradient space curve, and determine the configuration of the simulated part in combination with the test conditions of the testing machine. Step S2 specifically includes the following steps: S21: Based on the stress field data of the disk's characteristic structure, establish an xyz coordinate system, extract the position coordinates (x, y, z) of the nodes in the finite element model, and the stress values ​​in the x, y, z, xy, xz, and yz directions: S22: The moving least squares method is used to establish the influence radius with the nodes of the finite element model as the center, and a quadratic stress field function is constructed within the influence domain; S23: Calculate the Hessian matrix of the stress field using the weighted least squares method, perform eigenvalue decomposition on the Hessian matrix to obtain the direction of maximum curvature, and form a stress gradient space curve according to a set step size. The size iteration formula is as follows: ； In the formula, ΔL denoted as step size, σ yield is the material yield strength, tn is the current cross-sectional size, tn+1 is the cross-sectional size of the next iteration step, and ∇σn is the design stress gradient.

2. The design method for a simulated wheel feature structure based on additive manufacturing as described in claim 1, characterized in that, The steps between S21 and S22 include: Remove edge nodes from the finite element model and perform Kriging interpolation on the missing data.

3. The design method for a simulated wheel feature structure based on additive manufacturing as described in claim 1, characterized in that, The secondary stress field function is as follows: ； In the formula, x is the x-coordinate of the finite element model node in the xyz coordinate system, y is the y-coordinate of the finite element model node in the xyz coordinate system, z is the z-coordinate of the finite element model node in the xyz coordinate system, σ(x,y,z) is the stress of the finite element model node, and a0, a1, a2, a3, a4, a5, a6...a n-2 a n-1 a n For the corresponding coefficients.

4. The design method for a simulated wheel feature structure based on additive manufacturing as described in claim 3, characterized in that, The Hessian matrix is ​​as follows: ； In the matrix, The sign of the partial derivative. This is a second-order stress field function.

5. The design method for a simulated wheel feature structure based on additive manufacturing as described in claim 4, characterized in that, The specific steps for obtaining the direction of maximum curvature by performing eigenvalue decomposition on the Hessian matrix include: The Hessian matrix is ​​orthogonally diagonalized using the following formula: ； In the formula, Q is an orthogonal matrix, Ʌ is a diagonal matrix, and T is the matrix transpose symbol; Solve for the characteristic equation, which is as follows: ； In the formula, λ is the eigenvalue, and v is the unit eigenvector corresponding to λ; Find the largest λ among the eigenvalues max and the corresponding unit eigenvector v max v max This is the direction of maximum curvature.

6. The design method for a simulated wheel feature structure based on additive manufacturing principles according to any one of claims 1-5, characterized in that, The simulation component includes a clamping section and a test section, with the length of the clamping section being ≥ 5 times the maximum cross-sectional height difference of the test section.

7. The design method for a simulated wheel feature structure based on additive manufacturing principles according to any one of claims 1-5, characterized in that, Step S3 is followed by the following steps: Smooth out the sharp corners of the simulated component configuration.

8. The design method for a simulated wheel feature structure based on additive manufacturing principles according to any one of claims 1-5, characterized in that, Step S1 specifically includes the following steps: A parameterized model of the roulette wheel was established by softening through finite element analysis. The model was set according to the actual material parameters. A dense mesh was used in the characteristic structure area and a sparse mesh was used in the non-characteristic structure area. At the same time, it was ensured that the size ratio of adjacent elements was ≤1:

3. Centrifugal load, temperature field, and contact friction coefficient are applied to calculate the displacement of the disk. The displacement results of the feature structure are extracted as the displacement boundary conditions of the sub-model, and the mesh of the sub-model is refined to obtain high-resolution stress field data of the feature parts of the wheel.

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