Additive manufacturing exhaust frame feature mockup design method and feature mockup

Abstract

The application discloses a kind of additive manufacturing exhaust frame feature simulation piece design method and feature simulation piece, exhaust frame has outer ring, inner ring and branch plate, design method includes: exhaust frame structure finite element analysis and key position identification;Based on the absolute geometry fidelity configuration design of additive manufacturing defect recurrence;Load state decoupling and variable angle parameterization design;Three-dimensional space gradient tracking and matching optimization based on Hessian matrix.This design method designed simulation piece can truly reproduce the defect characteristics of heat accumulation and non-fusion of exhaust frame under certain geometric constraints, so that subsequent fatigue life prediction has real guiding significance, completely solves the defects of heat conduction distortion and scanning path change caused by geometric size modification of existing simulation piece.

Description

Technical Field

[0001] This invention relates to the field of aero-engine testing technology, and in particular, to a method for designing a feature simulation component of an additively manufactured exhaust frame. Furthermore, this invention also relates to a feature simulation component incorporating the aforementioned method for designing a feature simulation component of an additively manufactured exhaust frame. Background Technology

[0002] In existing turboshaft engines, the exhaust frame, as a crucial stator load-bearing structure, is complex and operates under harsh conditions. Using additive manufacturing for integral forming is a vital approach to achieving weight reduction and performance improvement. However, additive manufacturing is essentially a microscopic metallurgical process involving the interaction of a highly concentrated energy source (such as a laser) with metal powder. Its heat input and dissipation are extremely sensitive to geometric characteristics. For example, near the inner ring guide circle at the leading edge of the exhaust frame support blades, limited heat dissipation and frequent scanning path reversals can easily lead to uneven local energy density, resulting in unique process defects (such as incomplete fusion, porosity, and microcracks).

[0003] In research and development and service performance evaluation, existing technologies mainly face the following core technological contradictions: First, standard mechanical specimens cannot reflect real-world manufacturing defects. The formation of defects in additive manufacturing is not random but highly dependent on complex local geometries. The simple shapes of standard specimens (such as rods and plates) cannot reproduce the heat accumulation, frequent adjustments to laser scanning strategies, and significant residual stress concentration that occur in real components at thin walls and rounded corners. The defect characteristics generated internally are completely unrelated to actual load-bearing components, and the measured fatigue life data has low reference value in engineering applications. Second, conventional structural simulation design schemes have fundamental flaws. Existing technologies (such as those in publications CN121525416A and CN121543224A) mainly focus on the consistency of stress distribution in critical areas. They are usually based on standard specimen geometry and iteratively optimized by changing simple geometric dimensions (such as adjusting the V-notch and depth, scaling the leaf thickness proportionally, and modifying the chamfer radius). However, this is fatal for additive manufacturing components, as it destroys the geometric sensitivity boundary of additive manufacturing. In additive manufacturing, once the geometric dimensions (such as wall thickness and curvature) change, the heat accumulation rate, cooling gradient, and laser scanning path planning in that area will be completely changed. The internal defect types and distribution of the printed simulation parts are completely different from those of real components, losing the fundamental meaning of simulating the internal defects of real components. Furthermore, their stress extraction and equivalence methods are outdated. When extracting stress gradients, traditional simulation parts often rely on manually defining two-dimensional sections or straight paths, lacking rigorous mathematical field theory support, and cannot accurately describe the complex three-dimensional stress attenuation laws inside additive manufacturing. Third, the cost of testing with full-size real components is too high; directly using full-size components for testing is not only extremely costly and time-consuming, but also makes it difficult to conduct systematic in-situ studies of defects in specific areas. Summary of the Invention

[0004] This invention provides a design method and a feature simulation part for additive manufacturing exhaust frame features, in order to solve the technical problems of existing exhaust frame feature simulation parts failing to reflect real process defects and having high evaluation costs.

[0005] According to one aspect of the present invention, a method for designing a feature simulation component of an additively manufactured exhaust frame is provided. The exhaust frame has an outer ring, an inner ring, and a support plate. The design method includes: S1. Perform finite element analysis and key component identification on the original additively manufactured exhaust frame components, and extract core geometric parameters; S2. Construct the main structure of the feature simulation part, map the core geometric parameters in situ onto the feature simulation part, and lock the core geometric parameters in the subsequent design process; S3. On the feature simulation part with locked core geometric parameters, design one or more adjustable mechanical loading parameters, which are used to generate variable composite load states on external loading devices; S4. Construct the first stress field function of the key area of ​​the original component and the second stress field function of the characteristic simulation part corresponding to different mechanical loading parameter values; S5. Based on the Hessian matrix eigenvalue decomposition of the stress field function, automatically track the three-dimensional spatial curve with the fastest stress gradient decrease in the original component as the benchmark target, and track the corresponding three-dimensional spatial curve of the feature simulation component. S6. Calculate the stress distribution error on the three-dimensional space curve corresponding to the benchmark target and the feature simulation part, and minimize the error by iteratively optimizing the mechanical loading parameters to obtain the final feature simulation part configuration.

[0006] As a further improvement to the above technical solution, step S1 includes: S11. Establish a high-precision finite element model of the exhaust frame structure, and refine the mesh locally in areas with high stress based on empirical methods; S12. Apply typical working condition boundary conditions, including displacement constraints, temperature field loads, support reactions, and inertial loads, and perform multiphysics static simulation. S13. Identify high-stress hazardous areas in the structure and identify these areas as critical components.

[0007] As a further improvement to the above technical solution, the core geometric parameters include the radius of curvature of the outer contour of the support plate. Transition fillet radius and the thickness of the support plate cavity .

[0008] As a further improvement to the above technical solution, step S2 includes: S21. Accurately extract the core geometric parameters of key parts of the exhaust frame; S22. Design an opposing double V-shaped equivalent support structure and map the extracted parameters onto the simulated component in situ. , , In subsequent optimization steps, absolute locking will be implemented. , and The geometric features do not undergo deformation or scaling, thus ensuring that the thermal conduction boundary, thermal accumulation effect, and laser scanning path of the simulated part are absolutely consistent with the original part during the SLM additive manufacturing process.

[0009] As a further improvement to the above technical solution, step S3 includes: The angle between the equivalent support plate and the tension axis As a mechanical loading parameter.

[0010] As a further improvement to the above technical solution, step S3 includes: S31. Design adjustable mechanical loading parameters; S32. Parametric construction of different Angle-specific simulation components are loaded on a uniaxial tensile testing machine, based on the included angle. The function decomposes the axial tensile load into a combined tensile and bending load acting on the critical section.

[0011] As a further improvement to the above technical solution, step S4 includes: reconstructing the quadratic continuous stress field function using the moving least squares method. , .

[0012] As a further improvement to the above technical solution, step S5 includes: S51. Construct the Hessian matrix H of the continuous stress field; perform orthogonal diagonalization and eigenvalue decomposition on it. The unit eigenvector corresponding to the eigenvalue with the largest absolute value That is, the direction of principal curvature in space where stress decreases the fastest; S52. Starting from the point of maximum stress, move along with small steps. Continuing to step-track and update the matrix in real time, the three-dimensional stress gradient space curve of the exhaust frame is accurately extracted. Extract specific Space curve of the under-angle simulation component .

[0013] As a further improvement to the above technical solution, step S6 includes: Construct based on arc length Mean Absolute Error (MAE) Objective Function ; Different iterative calculations The MAE value under the angle, when the MAE reaches its minimum and meets the engineering threshold, this The configuration corresponding to the angle is the final feature simulation part.

[0014] According to another aspect of the present invention, a feature simulation component is also provided, which includes the above-described additive manufacturing exhaust frame feature simulation component design method.

[0015] The present invention has the following beneficial effects: This design method involves finite element analysis and key component identification of the original additively manufactured exhaust frame component, extracting core geometric parameters. The main structure of the feature simulation part is then constructed and mapped in situ onto the feature simulation part based on these core geometric parameters. These core geometric parameters are then locked during subsequent design processes. The designed simulation part can realistically reproduce the thermal accumulation and non-fusion defects of the exhaust frame under specific geometric constraints, providing genuine guidance for subsequent fatigue life prediction. This method completely solves the defects of existing simulation parts caused by geometric dimension modifications, such as heat conduction distortion and scanning path changes. On the feature simulation part with locked core geometric parameters, one or more adjustable mechanical loading parameters are designed to generate variable composite load states on an external loading device. Furthermore, by changing the mechanical loading parameters to generate variable composite load states on an external loading device, this avoids the need for a customized, complex multi-channel coordinated loading test bench. The completed component-level tests reduced testing costs and design thresholds. By constructing the first stress field function of the key area of ​​the original component and the second stress field function of the characteristic simulation part corresponding to different mechanical loading parameter values, based on the Hessian matrix eigenvalue decomposition of the stress field function, the three-dimensional space curve with the fastest stress gradient descent in the original component is automatically tracked as the benchmark target, and the corresponding three-dimensional space curve of the characteristic simulation part is tracked. This method abandons the traditional method of extracting stress along a two-dimensional plane or by manually drawing lines, and introduces the Hessian matrix algorithm to derive the direction of maximum curvature of the three-dimensional stress field, so that the matching of mechanical states has a rigorous mathematical basis and extremely high fidelity. Finally, the stress distribution error on the corresponding three-dimensional space curve of the benchmark target and the characteristic simulation part is calculated, and the error is minimized by iteratively optimizing the mechanical loading parameters, thereby obtaining the final configuration of the characteristic simulation part and giving the characteristic simulation part design extremely high mathematical rigor.

[0016] 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

[0017] The accompanying drawings, which form part of this application, 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: Figure 1 This is a schematic diagram of the finite element model of the exhaust frame in the prior art; Figure 2 This is a simplified local stress diagram of the principal stress cloud diagram of the exhaust frame according to a preferred embodiment of the present invention; Figure 3 This is an equivalent geometric feature diagram of a feature simulation component according to a preferred embodiment of the present invention. Figure 1 ; Figure 4 This is an equivalent geometric feature diagram of a feature simulation component according to a preferred embodiment of the present invention. Figure 2 ; Figure 5 This is an equivalent geometric feature diagram of a feature simulation component according to a preferred embodiment of the present invention. Figure 3 ; Figure 6 This is an equivalent geometric feature diagram of a feature simulation component according to a preferred embodiment of the present invention. Figure 4 ; Figure 7 This is a schematic diagram of the simulated component with varying included angle α according to a preferred embodiment of the present invention; Figure 8 This is a schematic diagram comparing the principal stress gradients of the original component and the simulated component in a preferred embodiment of the present invention; Figure 9 This is an optimized principal stress cloud diagram of a feature simulation part with α=50°, according to a preferred embodiment of the present invention. Detailed Implementation

[0018] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below.

[0019] Figure 2 This is a simplified local stress diagram of the principal stress cloud diagram of the exhaust frame according to a preferred embodiment of the present invention; Figure 3 This is an equivalent geometric feature diagram of a feature simulation component according to a preferred embodiment of the present invention. Figure 1 ; Figure 4 This is an equivalent geometric feature diagram of a feature simulation component according to a preferred embodiment of the present invention. Figure 2 ; Figure 5 This is an equivalent geometric feature diagram of a feature simulation component according to a preferred embodiment of the present invention. Figure 3 ; Figure 6 This is an equivalent geometric feature diagram of a feature simulation component according to a preferred embodiment of the present invention. Figure 4 ; Figure 7 This is a schematic diagram of the simulated component with varying included angle α according to a preferred embodiment of the present invention; Figure 8 This is a schematic diagram comparing the principal stress gradients of the original component and the simulated component in a preferred embodiment of the present invention; Figure 9 This is an optimized principal stress cloud diagram of a feature simulation part with α=50°, according to a preferred embodiment of the present invention.

[0020] like Figures 1 to 9 As shown in this embodiment, the additive manufacturing exhaust frame feature simulation part design method includes an exhaust frame with an outer ring, an inner ring, and a support plate. The design method includes: S1. Perform finite element analysis and key component identification on the original additively manufactured exhaust frame components, and extract core geometric parameters; S2. Construct the main structure of the feature simulation part, map the core geometric parameters in situ onto the feature simulation part, and lock the core geometric parameters in the subsequent design process; S3. On the feature simulation part with locked core geometric parameters, design one or more adjustable mechanical loading parameters, which are used to generate variable composite load states on external loading devices; S4. Construct the first stress field function of the key area of ​​the original component and the second stress field function of the characteristic simulation part corresponding to different mechanical loading parameter values; S5. Based on the Hessian matrix eigenvalue decomposition of the stress field function, the three-dimensional spatial curve with the fastest stress gradient decrease in the original component is automatically tracked as the benchmark target, and the corresponding three-dimensional spatial curve of the feature simulation component is tracked. S6. Calculate the stress distribution error on the three-dimensional space curve corresponding to the benchmark target and the feature simulation part, and minimize the error by iteratively optimizing the mechanical loading parameters to obtain the final feature simulation part configuration.

[0021] Understandably, this design method involves performing finite element analysis and identifying key components of the original additively manufactured exhaust frame to extract core geometric parameters. The main structure of the feature simulation part is then constructed and mapped in situ onto the feature simulation part based on these core geometric parameters. These core geometric parameters are then locked during subsequent design processes. The designed simulation part can realistically reproduce the exhaust frame's thermal accumulation and lack of fusion defects under specific geometric constraints, providing genuine guidance for subsequent fatigue life prediction. This method completely solves the defects of existing simulation parts caused by geometrical modifications, such as heat conduction distortion and scanning path changes. On the feature simulation part with locked core geometric parameters, one or more adjustable mechanical loading parameters are designed. These parameters are used to generate variable composite load states on external loading devices. Furthermore, by changing the mechanical loading parameters to generate variable composite load states on external loading devices, the method avoids the need for customized complex multi-channel coordinated loading tests. The component-level testing, which can only be completed on a test bench, reduces testing costs and design thresholds. By constructing the first stress field function of the key area of ​​the original component and the second stress field function of the characteristic simulation part corresponding to different mechanical loading parameter values, based on the Hessian matrix eigenvalue decomposition of the stress field function, the system automatically tracks the three-dimensional spatial curve with the fastest stress gradient descent in the original component as the benchmark target and tracks the corresponding three-dimensional spatial curve of the characteristic simulation part. This method abandons the traditional method of extracting stress along a two-dimensional plane or by manually drawing lines, and introduces the Hessian matrix algorithm to derive the direction of maximum curvature of the three-dimensional stress field, so that the matching of mechanical states has a rigorous mathematical basis and extremely high fidelity. Finally, the stress distribution error on the corresponding three-dimensional spatial curve of the benchmark target and the characteristic simulation part is calculated, and the mechanical loading parameters are iteratively optimized to minimize the error, thereby obtaining the final configuration of the characteristic simulation part and giving the characteristic simulation part design extremely high mathematical rigor.

[0022] In some preferred embodiments, step S1 includes: S11. Establish a high-precision finite element model of the exhaust frame structure, and refine the mesh locally in areas with high stress based on empirical methods; in some embodiments, the model is divided using a hexahedral mesh, and local refinement is performed in potentially high stress areas such as the connection between the support plate and the inner and outer rings, and the mesh size can be controlled within 0.5 mm. S12. Apply typical working condition boundary conditions, including displacement constraints, temperature field loads, support reactions, and inertial loads, and perform multiphysics static simulation. S13. Identify high-stress hazardous areas in the structure and pinpoint these areas as critical components. Extensive practical application research has revealed that under radial deformation, the inner ring of the exhaust frame exerts a tensile force on the support plate, causing stress concentration near the transition fillet of the inner ring at the leading edge of the support plate blades, resulting in a composite stress state dominated by tension. In a specific embodiment, after static analysis, the principal stress cloud diagram is extracted as follows: Figure 2As shown, the results indicate that under radial deformation, the inner ring exerts a strong tensile force on the support plate, resulting in significant stress concentration at the root of the transition fillet near the inner ring at the leading edge of the support plate blade. The maximum principal stress reaches 850 MPa, thus identifying this transition fillet area as a key design component.

[0023] In some preferred embodiments, step S2 includes: S21. Accurately extract the core geometric parameters of key components of the exhaust frame; among which, the core geometric parameters include the radius of curvature of the outer contour of the support plate. Transition fillet radius and the thickness of the support plate cavity The core geometric parameters (thickness, curvature, chamfer) are highly correlated with the heat accumulation and scanning path in additive manufacturing. By locking the core geometric parameters, it is possible to reproduce the unique process defects of additive manufacturing in situ on the feature simulation part. S22. Design an opposing double V-shaped equivalent support structure to simplify the experimental loading and map the extracted parameters in situ onto the simulated component. , , In subsequent optimization steps, absolute locking will be implemented. , and The geometric features remain unchanged and do not scale, thus ensuring that the heat conduction boundary, heat accumulation effect, and laser scanning path of the simulated part are absolutely consistent with the original component during the SLM additive manufacturing process. That is, a "geometric feature locking" design criterion based on the fidelity of additive manufacturing defects is set. In the design of the feature simulated part, the core geometric parameters (thickness, curvature, chamfer) that are highly related to the heat accumulation and scanning path of additive manufacturing are forcibly locked without any scaling or modification. This ensures that the mechanism of process defect initiation is restored and the heat accumulation and non-fusion defect characteristics of the exhaust frame under specific geometric constraints are truly reproduced. This makes the subsequent fatigue life prediction truly instructive and completely solves the defects of heat conduction distortion and scanning path change caused by the modification of geometric dimensions in existing simulated parts.

[0024] In some preferred embodiments, step S3 includes: The angle between the equivalent support plate and the tension axis As a mechanical loading parameter; it should be noted that, due to the fixed geometric features, it cannot be used to adjust stress. Therefore, this design method introduces a completely new adjustable mechanical parameter, namely the angle between the equivalent support plate and the tension axis. As a mechanical loading parameter, it achieves mechanical equivalence; In some preferred embodiments, step S3 includes: S31. Design adjustable mechanical loading parameters ; Based on the geometric feature locking, design variables are introduced; S32. Parametric construction of different Angle-specific simulation components are loaded on a uniaxial tensile testing machine, based on the included angle. The function is to decompose the axial tensile load into a combined tensile and bending load acting on the critical section; adjust This allows for control over the strength of the bending effect, thereby precisely regulating the stress gradient at the root of the transition fillet without altering the geometry. Furthermore, in load decoupling design, in addition to employing a variable angle for the tension axis... The solution, for certain components dominated by pure bending or torsion, can also be equivalent to a loading scheme for a non-standard variable-angle three-point / four-point bending fixture; in a specific embodiment, respectively establish Simulation models at 0°, 15°, 30°, 45°, 50°, 55°, and 60°, all possessing identical key geometric features. , , The only difference is Due to the different angles, when an axial tensile load F is applied, the load acting on the critical section (root of the transition fillet) is decomposed into tensile components perpendicular to the section. and shear / bending components (See) Figure 9 By adjusting This allows for precise control of the stress gradient at the root without altering any geometry.

[0025] In some preferred embodiments, step S4 includes: reconstructing the quadratic continuous stress field function using the moving least squares method. , Key parts of the actual exhaust frame and each The finite element node data (position coordinates and corresponding principal stress values) of the corner simulation component were used to fit a continuously differentiable three-dimensional stress field function using the moving least squares method.

[0026] In some preferred embodiments, step S5 includes: S51. Construct the Hessian matrix of the continuous stress field. Perform orthogonal diagonalization and eigenvalue decomposition on it. The unit eigenvector corresponding to the eigenvalue with the largest absolute value That is, the direction of the principal curvature in space where the stress decreases the fastest; where, as express The second-order partial derivative with respect to the x-direction is the local curvature of the stress field along the x-direction; The mixed second-order partial derivatives represent the coupled influence of the x and y spatial directions on stress variation; the direction of the maximum eigenvalue of the Hessian represents the direction of the maximum second-order curvature. The continuous stress field is reconstructed using the moving least squares method, and the fastest descent path of the three-dimensional spatial gradient is accurately extracted through Hessian matrix eigenvalue decomposition. Specifically, starting from the maximum stress point of the actual exhaust frame, the Hessian matrix H at that point is calculated, and eigenvalue decomposition is performed on H to obtain three eigenvalues ​​and their corresponding eigenvectors. The eigenvalue with the largest absolute value corresponds to the unit eigenvector. This direction is the three-dimensional spatial direction (principal curvature direction) where the stress gradient decreases the fastest at this point. S52. Starting from the point of maximum stress, move along with small steps. Continuing to step-track and update the matrix in real time, the three-dimensional stress gradient space curve of the exhaust frame is accurately extracted. Extract specific Space curve of the under-angle simulation component This method abandons the traditional approach of extracting stress along a two-dimensional plane or by manually drawing lines. Instead, it introduces the Hessian matrix algorithm to derive the direction of maximum curvature in the three-dimensional stress field, providing a rigorous mathematical basis and extremely high fidelity for matching the mechanical state. Starting from the point of maximum stress, along the direction... Moving to the next point in 0.2mm increments, the Hessian matrix is ​​recalculated and the direction is updated at that point; this process is repeated until the stress value decays to 10% of the maximum stress, ultimately obtaining a three-dimensional spatial curve, namely the "stress gradient master path" of the actual exhaust frame. For each... The simulation component at the corner repeats the above process to obtain the corresponding space curve.

[0027] In some preferred embodiments, step S6 includes: Construct based on arc length Mean Absolute Error (MAE) Objective Function In the formula, s is the arc length coordinate along the spatial stress gradient curve, ds is a small arc length element, L is the total curve length from the point of maximum stress along the principal stress gradient path to the endpoint, and 1 / L is used to convert the integral error into the average error, so as to avoid the cumulative error naturally becoming larger as the path becomes longer. This represents the stress value of the actual exhaust frame structural component at arc length s on the principal stress gradient space curve, where real represents the actual structural component. This represents the maximum stress value at the critical area of ​​the actual exhaust frame or the starting point of the tracking curve, used to normalize the stress curve of the actual structural component. This represents the stress value at arc length s on the principal stress gradient space curve of the simulated part when the included angle is α. This represents the maximum stress value at the critical region of the simulated part or the starting point of the tracking curve under the included angle α, and is used to normalize the stress curve of the simulated part. Different iterative calculations The MAE value under the angle, when the MAE reaches its minimum and meets the engineering threshold, this The configuration corresponding to the angle is the final feature simulation part; the normalized stress integral error (MAE) on this path is used as the sole criterion to give the simulation part design extremely high mathematical rigor; It should be noted that, in addition to MAE, the root mean square error (RMSE) can also be used to determine the error evaluation function for space curves; the optimal angle The optimization process can be combined with genetic algorithms or response surface surrogate models to upgrade discrete angle enumeration to automated and fast solution of continuous intervals.

[0028] In one specific embodiment, when When the angle is 50°, the MAE value is the smallest, at only 1.11%, which is far below the commonly used engineering threshold of 5%. This indicates that when the included angle is 50°, the three-dimensional stress gradient distribution of the simulated component under uniaxial tension is extremely consistent with that of the real exhaust frame. Figure 9 Showing The principal stress cloud diagram of the simulated part at 50° angle shows its stress distribution pattern as... Figure 2 The stress concentration characteristics of the actual components shown are highly consistent. Selective laser melting (SLM) technology was employed, using GH4169 powder as the raw material, according to... An optimized configuration with a 50° angle was used to print a simulated exhaust frame feature. The simulated component was then mounted on a standard uniaxial tensile fatigue testing machine for fatigue testing. The test results showed that the final fatigue fracture location of the simulated component precisely occurred at the root of the transition fillet of the equivalent support plate. This perfectly matches the maximum stress point predicted by finite element analysis and the expected process defect sensitive area (thin wall, small fillet). These physical test results fully demonstrate that the simulated component designed in this invention can faithfully reproduce the stress state and fatigue failure mode of real additively manufactured complex components on conventional testing equipment.

[0029] On the other hand, a preferred embodiment of the present invention also provides a feature simulation component, which applies the above-described additive manufacturing exhaust frame feature simulation component design method.

[0030] In the description of this invention, it should be noted that the terms "upper", "lower", "front", "rear", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0031] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0032] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for designing a feature simulation component of an additively manufactured exhaust frame, the exhaust frame having an outer ring, an inner ring, and a support plate, characterized in that, Design methods include: S1. Perform finite element analysis and key component identification on the original additively manufactured exhaust frame components, and extract core geometric parameters; S11. Establish a high-precision finite element model of the exhaust frame structure, and refine the mesh locally in areas with high stress based on empirical methods; S12. Apply typical working condition boundary conditions, including displacement constraints, temperature field loads, support reactions, and inertial loads, and perform multiphysics static simulation. S13. Identify high-stress hazardous areas in the structure and identify these areas as critical components; S2. Construct the main structure of the feature simulation part, map the core geometric parameters in situ onto the feature simulation part, and lock the core geometric parameters in the subsequent design process; S3. On the feature simulation part with locked core geometric parameters, design one or more adjustable mechanical loading parameters, which are used to generate variable composite load states on external loading devices; S4. Construct the first stress field function of the key area of ​​the original component and the second stress field function of the characteristic simulation part corresponding to different mechanical loading parameter values; S5. Based on the Hessian matrix eigenvalue decomposition of the stress field function, automatically track the three-dimensional spatial curve with the fastest stress gradient decrease in the original component as the benchmark target, and track the corresponding three-dimensional spatial curve of the feature simulation component. S6. Calculate the stress distribution error on the three-dimensional space curve corresponding to the benchmark target and the feature simulation part, and minimize the error by iteratively optimizing the mechanical loading parameters to obtain the final feature simulation part configuration.

2. The additive manufacturing exhaust frame feature simulation design method according to claim 1, characterized in that, Core geometric parameters include the radius of curvature of the outer contour of the support plate. Transition fillet radius and the thickness of the support plate cavity .

3. The additive manufacturing exhaust frame feature simulation design method according to claim 2, characterized in that, Step S2 includes: S21. Accurately extract the core geometric parameters of key parts of the exhaust frame; S22. Design an opposing double V-shaped equivalent support structure and map the extracted parameters onto the simulated component in situ. , , In subsequent optimization steps, absolute locking will be implemented. , and The geometric features do not undergo deformation or scaling, thus ensuring that the thermal conduction boundary, thermal accumulation effect, and laser scanning path of the simulated part are absolutely consistent with the original part during the SLM additive manufacturing process.

4. The additive manufacturing exhaust frame feature simulation design method according to claim 3, characterized in that, Step S3 includes: The angle between the equivalent support plate and the tension axis As a mechanical loading parameter.

5. The additive manufacturing exhaust frame feature simulation design method according to claim 4, characterized in that, Step S3 includes: S31. Design adjustable mechanical loading parameters; S32. Parametric construction of different Angle-specific simulation components are loaded on a uniaxial tensile testing machine, based on the included angle. The function decomposes the axial tensile load into a combined tensile and bending load acting on the critical section.

6. The additive manufacturing exhaust frame feature simulation design method according to claim 5, characterized in that, Step S4 includes: reconstructing the quadratic continuous stress field function using the moving least squares method.

7. The additive manufacturing exhaust frame feature simulation design method according to claim 6, characterized in that, Step S5 includes: S51. Construct the Hessian matrix H of the continuous stress field; perform orthogonal diagonalization and eigenvalue decomposition on it. The unit eigenvector corresponding to the eigenvalue with the largest absolute value That is, the direction of principal curvature in space where stress decreases the fastest; S52. Starting from the point of maximum stress, move along with small steps. Continuing to step-track and update the matrix in real time, the three-dimensional stress gradient space curve of the exhaust frame is accurately extracted. ,extract Space curve of the under-angle simulation component .

8. The additive manufacturing exhaust frame feature simulation design method according to claim 7, characterized in that, Step S6 includes: Construct based on arc length Mean Absolute Error (MAE) Objective Function In the formula, s is the arc length coordinate along the spatial stress gradient curve, ds is a small arc length element, L is the total curve length from the point of maximum stress along the principal stress gradient path to the end point, and 1 / L is used to convert the integral error into the average error, so as to avoid the cumulative error naturally becoming larger as the path becomes longer. This represents the stress value of the actual exhaust frame structural component at arc length s on the principal stress gradient space curve, with the subscript real indicating the actual structural component. This represents the maximum stress value at the critical area of ​​the actual exhaust frame or the starting point of the tracking curve, used to normalize the stress curve of the actual structural component. This represents the stress value at arc length s on the principal stress gradient space curve of the simulated part when the included angle is α. This represents the maximum stress value at the critical region of the simulated part or the starting point of the tracking curve under the included angle α, and is used to normalize the stress curve of the simulated part. Different iterative calculations The MAE value under the angle, when the MAE reaches its minimum and meets the engineering threshold, this The configuration corresponding to the angle is the final feature simulation part.

9. A feature simulation component, characterized in that, The additive manufacturing exhaust frame feature simulation design method as described in any one of claims 1-8 is applied.

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