Method, device and equipment for obtaining design scheme of die-casting vehicle body structural member and medium

Abstract

The invention discloses a design scheme obtaining method, device and equipment for a die-casting vehicle body structural member and a medium, and relates to the technical field of technological parameter design, and the method comprises the steps that a main design area of an integrated die-casting aluminum alloy material is analyzed; a tensile test is conducted on the main design area of the integrated die-casting aluminum alloy material, and mechanical property parameters are obtained; establishing a body-in-white finite element model and performing bending-torsional rigidity simulation calculation to obtain a body-in-white bending-torsional rigidity result; establishing an equivalent boundary condition for the rear floor structure based on a body-in-white bending-torsional rigidity result, and performing equivalent simulation analysis to obtain an equivalent simulation analysis result; establishing an optimization model of the rear floor structure according to an equivalent simulation analysis result; performing topological optimization on the optimization model to obtain a topological optimization result; carrying out lightweight design on the rear floor structure based on a topological optimization result; checking the performance of the rear floor structure after the lightweight design; and adjusting the rear floor structure after lightweight design according to a checking result.

Description

Technical Field

[0001] The present application relates to the technical field of process parameter design, and in particular to a method, device, equipment and medium for obtaining a design scheme for a die-cast vehicle body structural part. Background Art

[0002] With the improvement of the automobile industry, large-scale one-piece die-cast aluminum alloy body structures are gradually being used to replace traditional stamping-welding body-in-white (BIW) structures. Compared with traditional steel stamping-welding bodies, aluminum alloy one-piece die-cast bodies are die-casted in one step by large die-casting machines. It integrates the production of multiple parts in traditional bodies, reduces manufacturing processes, improves production efficiency, and is expected to achieve cost reduction and efficiency improvement. Research on the lightweight design method of one-piece die-casting structure has guiding significance for its iterative optimization design.

[0003] Due to the high degree of manufacturing integration, the one-piece die-cast body structure is relatively complex, which poses a challenge to the traditional body simulation and design methods. Therefore, some optimization methods for body die-castings have been proposed one after another. Although the size and complexity of the structure are different, the method theory can still be used as a reference to explore the lightweight design method of body castings from small to large, from simple to complex. Since the one-piece die-cast body structure is a typical variable thickness structure, its thickness is usually distributed in the range of 2-6mm. If the traditional shell unit is simply used to carry out finite element analysis and optimization, a large amount of complex pre-processing work is required, which affects the design efficiency; on the other hand, if the solid unit modeling is used and substituted into the analysis and optimization of the body-in-white level, it puts forward a great demand for computing resources: taking the rear floor structure of the one-piece die-cast body as an example, under the premise of retaining the detailed features, if the tetrahedral unit mesh is used, its order of magnitude is roughly in the tens of millions, which is not conducive to the finite element analysis and optimization design of the body-in-white level. Summary of the invention

[0004] The purpose of this application is to provide a method, device, equipment and medium for obtaining a design solution for a die-cast vehicle body structural part.

[0005] To achieve the above objectives, this application provides the following solutions:

[0006] In a first aspect, the present application provides a method for obtaining a design solution for a die-cast vehicle body structural component, comprising:

[0007] Analyze the main design areas of one-piece die-cast aluminum alloy materials;

[0008] Performing a tensile test on the main design area of ​​the one-piece die-cast aluminum alloy material to obtain mechanical property parameters;

[0009] Establish the BIW finite element model and perform bending and torsional stiffness simulation calculation to obtain the BIW bending and torsional stiffness results;

[0010] Based on the BIW bending and torsional stiffness results, equivalent boundary conditions are established for the rear floor structure, and equivalent simulation analysis is performed to obtain equivalent simulation analysis results;

[0011] Establishing an optimization model of the rear floor structure according to the equivalent simulation analysis results;

[0012] Performing topology optimization on the optimization model to obtain a topology optimization result;

[0013] Performing a lightweight design on the rear floor structure based on the topology optimization result;

[0014] Perform performance verification on the lightweight rear floor structure;

[0015] The lightweight designed rear floor structure is adjusted according to the verification result.

[0016] Optionally, the step of analyzing the main design area of ​​the integral die-casting aluminum alloy material comprises:

[0017] The location, original structure and overlapping surfaces of the one-piece die-cast floor were analyzed to determine the main design areas.

[0018] Optionally, the step of performing a tensile test on a main design area of ​​the one-piece die-cast aluminum alloy material to obtain mechanical property parameters comprises:

[0019] A tensile test is carried out in accordance with preset standard regulations to obtain the mechanical property parameters of the one-piece die-cast aluminum alloy material as parameter input for finite element analysis and topology optimization calculations.

[0020] Optionally, the step of establishing a BIW finite element model and performing a bending-torsion stiffness simulation calculation to obtain a BIW bending-torsion stiffness result comprises:

[0021] A finite element model of the body-in-white is established, the model is meshed using quadrilateral shell elements, and a bending and torsional stiffness simulation calculation of the body-in-white level is performed according to preset standard regulations to obtain the body-in-white bending and torsional stiffness results.

[0022] Optionally, the step of establishing equivalent boundary conditions for the rear floor structure based on the BIW bending and torsional stiffness results, and performing equivalent simulation analysis to obtain equivalent simulation analysis results comprises:

[0023] Based on the bending and torsional stiffness results of the body in white, equivalent boundary conditions are established for the rear floor structure, and equivalent simulation analysis is carried out. The displacement responses in the equivalent simulation analysis results of the rear floor bending and torsional working conditions are extracted, and the bending and torsional stiffness of the rear floor structure are calculated as equivalent simulation analysis results.

[0024] Optionally, the step of establishing the optimization model of the rear floor structure according to the equivalent simulation analysis result comprises:

[0025] An extended design domain model is established according to the equivalent simulation analysis results, and the side surface and the floor plane area of ​​the rear floor are used as the design area, and draft constraints are applied in the draft direction of the die-casting structure.

[0026] Optionally, the step of performing topology optimization on the optimization model to obtain a topology optimization result includes:

[0027] The optimization model is optimized by a linear weighted method based on the SIMP method. The optimization constraints are imposed on the equivalent model in combination with the casting process. Different weighting schemes are preset, and the connectivity and rationality of the optimized structure and the change in the weighted flexibility of the structure are used to determine the weighting coefficient scheme.

[0028] In a second aspect, the present application provides a design scheme acquisition device for a die-cast vehicle body structural component, comprising:

[0029] Acquisition module for analyzing the main design areas of one-piece die-cast aluminum alloy materials;

[0030] Performing a tensile test on the main design area of ​​the one-piece die-cast aluminum alloy material to obtain mechanical property parameters;

[0031] Establish the BIW finite element model and perform bending and torsional stiffness simulation calculation to obtain the BIW bending and torsional stiffness results;

[0032] Used to establish equivalent boundary conditions for the rear floor structure based on the BIW bending and torsional stiffness results, and perform equivalent simulation analysis to obtain equivalent simulation analysis results;

[0033] Used to establish an optimization model of the rear floor structure according to the equivalent simulation analysis results;

[0034] Performing topology optimization on the optimization model to obtain a topology optimization result;

[0035] A design module, performing a lightweight design on the rear floor structure based on the topology optimization result;

[0036] Perform performance verification on the lightweight rear floor structure;

[0037] The lightweight designed rear floor structure is adjusted according to the verification result.

[0038] Optionally, the acquisition module is further used to:

[0039] The location, original structure and overlapping surfaces of the one-piece die-cast floor were analyzed to determine the main design areas.

[0040] Optionally, the acquisition module is further used to:

[0041] A tensile test is carried out in accordance with preset standard regulations to obtain the mechanical property parameters of the one-piece die-cast aluminum alloy material as parameter input for finite element analysis and topology optimization calculations.

[0042] Optionally, the acquisition module is further used to:

[0043] A finite element model of the body-in-white is established, the model is meshed using quadrilateral shell elements, and a bending and torsional stiffness simulation calculation of the body-in-white level is performed according to preset standard regulations to obtain the body-in-white bending and torsional stiffness results.

[0044] Optionally, the acquisition module is further used to:

[0045] Based on the bending and torsional stiffness results of the body in white, equivalent boundary conditions are established for the rear floor structure, and equivalent simulation analysis is carried out. The displacement responses in the equivalent simulation analysis results of the rear floor bending and torsional working conditions are extracted, and the bending and torsional stiffness of the rear floor structure are calculated as equivalent simulation analysis results.

[0046] Optionally, the acquisition module is further used to:

[0047] An extended design domain model is established according to the equivalent simulation analysis results, and the side surface and the floor plane area of ​​the rear floor are used as the design area, and draft constraints are applied in the draft direction of the die-casting structure.

[0048] Optionally, the design module is further used to:

[0049] The optimization model is optimized by a linear weighted method based on the SIMP method. The optimization constraints are imposed on the equivalent model in combination with the casting process. Different weighting schemes are preset, and the connectivity and rationality of the optimized structure and the change in the weighted flexibility of the structure are used to determine the weighting coefficient scheme.

[0050] In a third aspect, the present application provides a computer device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the method for obtaining a design solution for a die-cast vehicle body structure as described in any one of the above.

[0051] In a fourth aspect, the present application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method for obtaining a design solution for a die-cast vehicle body structural part as described in any one of the above.

[0052] In a fifth aspect, the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the steps of any of the above-mentioned methods for obtaining a design solution for a die-cast vehicle body structural part.

[0053] According to the specific embodiments provided in this application, this application discloses the following technical effects:

[0054] The present application provides a method, device, equipment and medium for obtaining a design scheme for a die-cast vehicle body structural part. By deeply analyzing the main design areas of the one-piece die-cast aluminum alloy material and obtaining its mechanical performance parameters, a finite element model of the body-in-white is established to perform bending and torsional stiffness simulation calculations, equivalent boundary conditions are established for the rear floor structure and equivalent simulation analysis is performed, and then an optimization model is established to perform topological optimization, ultimately achieving a lightweight design. Performance verification is performed to ensure that the design meets the requirements, thereby achieving multiple effects of lightweight, high performance and reliability at the technical level, which not only improves design efficiency but also reduces manufacturing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0056] Figure 1 A schematic flow chart of a method for obtaining a design solution for a die-cast vehicle body structural component provided in one embodiment of the present application;

[0057] Figure 2 A displacement cloud diagram of a bending condition of a method for obtaining a design solution for a die-cast vehicle body structural component provided in one embodiment of the present application;

[0058] Figure 3 A displacement cloud diagram of a torque condition of a method for obtaining a design solution for a die-cast vehicle body structure provided in one embodiment of the present application;

[0059] Figure 4 A schematic diagram of an equivalent boundary condition of the torsional stiffness of a rear floor in a method for obtaining a design solution of a die-cast vehicle body structure provided in an embodiment of the present application;

[0060] Figure 5 A schematic diagram of an equivalent boundary condition of the bending stiffness of a rear floor in a method for obtaining a design solution of a die-cast vehicle body structure provided in an embodiment of the present application;

[0061] Figure 6A schematic diagram of the draft direction of a rear floor panel of a method for obtaining a design solution for a die-cast vehicle body structure provided in one embodiment of the present application;

[0062] Figure 7 A schematic diagram of a finite element calculation model of a design domain of a method for obtaining a design solution for a die-cast vehicle body structural component provided in one embodiment of the present application;

[0063] Figure 8 A schematic diagram of an iterative curve for topological optimization of a floor structure after integral die-casting in a method for obtaining a design solution for a die-cast vehicle body structure provided in one embodiment of the present application;

[0064] Fig. 9 A schematic side view of a lightweight design solution of a method for obtaining a design solution for a die-cast vehicle body structural component provided in one embodiment of the present application;

[0065] Fig.10 A schematic diagram of a bottom-up effect of a lightweight design solution of a method for obtaining a design solution of a die-cast vehicle body structural component provided in an embodiment of the present application;

[0066] Fig.11 A schematic diagram of functional modules of a design scheme acquisition device for a die-cast vehicle body structural component provided in one embodiment of the present application;

[0067] Fig.12 A schematic diagram of the structure of a computer device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0068] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0069] like Figure 1 As shown, some embodiments of the present application provide a method for obtaining a design solution for a die-cast vehicle body structural component, which includes the following steps 101 to 109. Among them:

[0070] Step 101, analyzing the main design area of ​​the one-piece die-cast aluminum alloy material.

[0071] In the embodiment of the present application, the system conducts an in-depth analysis of the position, original structure and overlapping relationship with surrounding parts of the rear floor made of one-piece die-cast aluminum alloy material. Through the analysis, it can be determined which areas are the main design areas, that is, those areas that have a significant impact on the stiffness, strength and other properties of the rear floor.

[0072] Step 102: Perform a tensile test on the main design area of ​​the one-piece die-cast aluminum alloy material to obtain mechanical property parameters.

[0073] In the embodiment of the present application, the tensile test is a standard material testing method used to measure the mechanical behavior of materials under tensile loads. The system will perform tensile tests on the main design areas of the one-piece die-cast aluminum alloy material to obtain its mechanical performance parameters, such as tensile strength, yield strength, elongation, etc. These parameters are the basis for subsequent finite element analysis and optimization design.

[0074] Step 103, establishing a BIW finite element model and performing a bending torsional stiffness simulation calculation to obtain a bending torsional stiffness result of the BIW.

[0075] In the embodiment of the present application, the finite element model is a digital car body model used to simulate and analyze the behavior of the car body under stress. The system will establish a finite element model of the body in white and perform bending and torsional stiffness simulation calculations on it. Through calculation, the stiffness results of the body in white under bending and torsional conditions can be obtained, which are crucial for the subsequent establishment of equivalent boundary conditions of the rear floor.

[0076] Step 104: establishing equivalent boundary conditions for the rear floor structure based on the BIW bending and torsional stiffness results, and performing equivalent simulation analysis to obtain equivalent simulation analysis results.

[0077] In the embodiment of the present application, in order to simplify the analysis process, the system extracts the rear floor part from the complex body-in-white structure and sets the same boundary conditions as those in the body-in-white, i.e., equivalent boundary conditions. Then, an equivalent simulation analysis is performed on the rear floor structure to obtain its performance data under given boundary conditions, i.e., equivalent simulation analysis results. These results will be used for the subsequent optimization model establishment.

[0078] Step 105: establishing an optimization model of the rear floor structure according to the equivalent simulation analysis results.

[0079] In the embodiment of the present application, based on the equivalent simulation analysis results, the system will establish an optimization model for the rear floor structure. This model will be used in the subsequent topology optimization process to find the optimal material distribution and shape, thereby achieving lightweight design.

[0080] Step 106: Perform topology optimization on the optimization model to obtain a topology optimization result.

[0081] In the embodiment of the present application, topology optimization is a mathematical method used to reduce the amount of material while maintaining structural performance. The system will perform topology optimization calculations on the optimization model to obtain the optimal material distribution and shape. These results will be used to guide the subsequent lightweight design of the rear floor.

[0082] Step 107: Perform lightweight design on the rear floor structure based on the topology optimization result.

[0083] In the embodiment of the present application, based on the topology optimization results, the designer will perform a lightweight design on the rear floor structure, which usually involves modifying the shape and material distribution of the rear floor to achieve lightweight while meeting performance requirements.

[0084] Step 108, performing performance verification on the lightweight designed rear floor structure.

[0085] In the embodiment of the present application, in order to ensure that the rear floor structure after lightweight design meets the design requirements, the system will perform a performance check on it. This usually involves simulation analysis or experimental testing of the rear floor to verify whether its stiffness, strength and other properties meet the design requirements.

[0086] Step 109, adjusting the lightweight designed rear floor structure according to the verification result.

[0087] In the embodiment of the present application, if the verification result does not meet the design requirements, the system will adjust the lightweight designed rear floor structure according to the verification result. This usually involves further modification of the shape and material distribution of the rear floor to ensure that it meets the design requirements. Then, the performance verification may be performed again until the rear floor structure meets all design requirements.

[0088] The embodiment of the present application deeply analyzes the main design areas of the one-piece die-cast aluminum alloy material and obtains its mechanical property parameters, establishes a finite element model of the body-in-white to perform bending and torsional stiffness simulation calculations, establishes equivalent boundary conditions for the rear floor structure and performs equivalent simulation analysis, and then establishes an optimization model to perform topology optimization, ultimately achieving a lightweight design, and performing performance verification to ensure that the design meets the requirements, thereby achieving the multiple effects of lightweight, high performance and reliability at the technical level, which not only improves design efficiency but also reduces manufacturing costs.

[0089] Optionally, the step 101 includes: analyzing the position, original structure and overlapping surface of the integral die-cast floor to determine a main design area.

[0090] In the embodiment of the present application, the one-piece die-cast rear floor is usually located at the rear of the vehicle body and is an important part of the vehicle body structure. Its position determines its role in bearing the vehicle weight, transmitting force and torque. According to the force conditions of the vehicle during driving and the collision safety requirements, the rear floor needs to have sufficient strength and rigidity. At the same time, its position also affects the connection method and design considerations with other components.

[0091] The original structure of the one-piece die-cast rear floor may include the main body, the rib part, the connection points, etc. These components together determine the overall performance of the rear floor. The one-piece die-cast rear floor is usually made of aluminum alloy, which has the characteristics of light weight and high strength, but it is also necessary to consider factors such as its casting performance and heat treatment requirements. When analyzing the original structure, it is also necessary to consider the characteristics and requirements of the one-piece die-casting process, such as mold design, pouring system, cooling system, etc. These factors will affect the quality and performance of the final product.

[0092] The connection between the one-piece die-cast rear floor and other components (such as the front floor, rear longitudinal beam, etc.) is usually achieved through the overlap surface. The design of the overlap surface needs to ensure the reliability and stability of the connection. When analyzing the overlap surface, it is necessary to consider the stress conditions during the driving of the vehicle, including shear force, bending moment, etc., to ensure that the connection has sufficient strength and rigidity. For overlap surfaces that need to be sealed (such as the connection with the battery pack), sealing requirements also need to be considered to avoid liquid or gas leakage.

[0093] Based on the above analysis, the main design areas of the one-piece die-cast rear floor can be determined. These areas usually include stress concentration areas, areas near connection points, areas that require rib support, etc. After determining the main design areas, these areas can be optimized, such as adding ribs, adjusting wall thickness, optimizing connection methods, etc., to improve the overall performance of the rear floor.

[0094] Optionally, the step 102 includes: conducting a tensile test according to preset standard regulations to obtain mechanical property parameters of the one-piece die-cast aluminum alloy material as parameter input for finite element analysis and topology optimization calculation.

[0095] In the embodiment of the present application, firstly, according to the characteristics and application background of the one-piece die-cast aluminum alloy material, appropriate national and industry standards or internal enterprise standards are selected as the basis for the tensile test. These standards usually specify in detail the requirements for test equipment, sample preparation, test conditions, data processing, etc. Ensure that the entire process of the tensile test strictly follows the provisions of the selected standard to ensure the accuracy and comparability of the test results.

[0096] According to the standard requirements, cut specimens of specified size and shape from the one-piece die-cast aluminum alloy material. The preparation of the specimen needs to ensure the representativeness of the material and avoid the introduction of additional stress or defects due to cutting, processing and other factors. Use a tensile testing machine that meets the standards for testing. The testing machine should be able to accurately control the stretching speed and record key parameters such as force and displacement during the stretching process. Set appropriate environmental conditions such as test temperature and humidity, as well as test parameters such as stretching speed to ensure the reliability of the test results. During the stretching process, record the stress-strain curve, fracture strength, yield strength, elongation and other mechanical performance parameters of the specimen in real time.

[0097] The data recorded in the tensile test are processed and analyzed to calculate the mechanical properties of the material. These parameters are important indicators for evaluating material performance and are also the basis for subsequent finite element analysis and topology optimization calculations. For example, the fracture strength reflects the material's ability to resist fracture during the tensile process; the yield strength indicates the stress level at which the material begins to undergo plastic deformation; and the elongation reflects the material's ability to undergo plastic deformation.

[0098] The obtained mechanical property parameters are used as input to establish a finite element model of the one-piece die-cast aluminum alloy material. Through finite element analysis, the stress and strain distribution of the material under real working conditions can be simulated to evaluate the performance of the structure. In the topology optimization process, mechanical property parameters are also an indispensable input. Topology optimization aims to achieve lightweight design of the structure while maintaining or improving the performance of the structure by optimizing the distribution and shape of the material. Mechanical property parameters provide an important basis for the topology optimization algorithm to evaluate material performance and optimization direction.

[0099] Optionally, the step 103 includes: establishing a finite element model of the body-in-white, meshing the model using quadrilateral shell elements, and performing bending and torsional stiffness simulation calculations of the body-in-white level according to preset standard regulations to obtain body-in-white bending and torsional stiffness results.

[0100] In the embodiment of the present application, according to the actual geometric shape and structural characteristics of the body in white, a three-dimensional geometric model thereof is established using finite element analysis software (such as HyperMesh, ANSYS, Abaqus, etc.). In the modeling process, it is necessary to accurately reflect the various components of the body in white, including the frame, crossbeams, longitudinal beams, floor, roof, side panels, etc., as well as the connection methods and material properties between them.

[0101] Assign correct material properties to each component in the model, such as elastic modulus, Poisson's ratio, density, etc. These properties are usually obtained through material testing. For one-piece die-cast aluminum alloy materials, special attention should be paid to its complex material behaviors such as anisotropy and plastic deformation characteristics, and the material model should be adjusted accordingly.

[0102] Meshing is one of the key steps in finite element analysis, which directly affects the accuracy and efficiency of the calculation results. For complex structures such as the body-in-white, quadrilateral shell elements are usually used for meshing, because shell elements can effectively simulate the bending and torsion behavior of thin-walled structures. According to the geometric shape and force characteristics of the body-in-white, the model is divided into quadrilateral grids of moderate size and regular shape. The size of the grid needs to balance the calculation accuracy and calculation time. Usually, finer grids are required in key areas (such as stress concentration areas, connection points, etc.). After the meshing is completed, the mesh quality check is required to ensure that the continuity, orthogonality, distortion, etc. of the mesh meet the analysis requirements.

[0103] According to the preset standards (such as national standards, industry standards or internal enterprise standards), the bending and torsional conditions of the body in white are determined, and the corresponding loads and boundary conditions are applied. The bending condition usually simulates the vertical load applied to the vehicle during driving, while the torsional condition simulates the torque applied to the vehicle when driving on uneven roads. The finite element analysis software is used to simulate the bending and torsional stiffness of the body in white model. During the calculation process, the software will solve the stress and strain distribution of the body in white under various conditions, as well as the overall bending and torsional stiffness based on information such as mesh division, material properties, loading and boundary conditions.

[0104] After the simulation is completed, the results are post-processed and analyzed. The displacement, stress, strain and other key parameters of the body-in-white under bending and torsion conditions are extracted, and the bending stiffness and torsion stiffness of the body-in-white are calculated. According to the preset standards or design requirements, the stiffness performance of the body-in-white is evaluated to see whether it meets the requirements, and provide a basis for subsequent structural optimization.

[0105] Optionally, step 104 includes: establishing equivalent boundary conditions for the rear floor structure based on the bending and torsional stiffness results of the body-in-white, performing equivalent simulation analysis, and extracting displacement responses from equivalent simulation analysis results of bending and torsional working conditions of the rear floor, and calculating the bending and torsional stiffness of the rear floor structure as equivalent simulation analysis results.

[0106] In the embodiments of the present application, the stiffness performance of the body-in-white under bending and torsion conditions includes the overall displacement distribution, stress concentration areas, and stress conditions at key connection points. Based on the bending and torsion stiffness results of the body-in-white, boundary conditions that are directly related to or have a greater impact on the rear floor are identified, such as the stiffness of adjacent components, the location of connection points, and stress conditions. These boundary conditions will serve as the basis for subsequent equivalent simulation analysis to ensure that the analysis results of the rear floor can accurately reflect its actual stress state in the body-in-white. In the finite element analysis software, an equivalent boundary condition model of the rear floor is established based on the identified boundary conditions. This may include applying corresponding force or displacement constraints at key connection points, and simulating the stiffness effects of adjacent components.

[0107] According to the actual situation of the rear floor and the analysis requirements, set the simulation parameters, such as loading method, analysis step, solver, etc. Ensure that the simulation parameter settings can accurately reflect the stress conditions of the rear floor under real working conditions. Use finite element analysis software to perform equivalent simulation analysis on the rear floor. During the simulation process, the software will solve the displacement, stress and other responses of the rear floor under bending and torsion conditions based on the established equivalent boundary condition model and the set simulation parameters.

[0108] After the simulation is completed, the displacement response of the rear floor under bending and torsion conditions is extracted from the analysis results. This usually includes the displacement values ​​of key points, displacement distribution diagrams, etc. Based on the extracted displacement response, combined with the geometric dimensions, material properties and other information of the rear floor, the bending stiffness and torsion stiffness of the rear floor are calculated. The bending stiffness can be obtained by calculating the ratio between the displacement of the rear floor under bending conditions and the applied load; the torsion stiffness can be obtained by calculating the ratio between the torsion angle of the rear floor under torsion conditions and the applied load torque.

[0109] Evaluate the calculated bending and torsional stiffness of the rear floor to determine whether it meets the design requirements or industry standards. If the results do not meet the requirements, it may be necessary to adjust the structural design or material selection of the rear floor and re-perform equivalent simulation analysis until satisfactory results are obtained.

[0110] Exemplarily, the rear floor is deconstructed from the body-in-white bending and torsional stiffness results and displayed, for example Figure 2 is the displacement cloud diagram of the bending condition, Figure 3 The displacement cloud diagram of the torque condition is shown in Figure 2. The equivalent simulation analysis of the bending and torsion boundary conditions of the rear floor is performed to calculate the bending and torsion stiffness of the structure. The schematic diagram of the equivalent boundary conditions of the torsion stiffness of the designed rear floor is shown in Figure 2. Figure 4 The schematic diagram of the equivalent boundary conditions of the designed rear floor bending stiffness is as follows: Figure 5 . The specific process is as follows: Step 1, obtain the deformation form of the rear floor structure and the boundary force and displacement of the key overlap area. Step 2, imitate the analysis results of the body-in-white to establish the equivalent boundary conditions of the rear floor structure. Full constraints are performed at the rear suspension point of the rear floor. The holes in the overlap area of ​​the rear floor and the door sill beam are connected by RB2 units, and a concentrated force F of 4080N is applied to the connection point. The direction of the concentrated force is the same during the bending condition and opposite to the bending condition. Analyze the overlap relationship and structural characteristics of the rear floor, and use the direction with smaller structural deformation as the constraint direction. Carry out finite element analysis based on the designed boundary conditions, analyze the deformation form of the structure, and calculate the bending and torsional stiffness. Step 3, carry out comparative analysis, verify the equivalent calculation model established in step 2, and adjust the loading and constraints. Step 4, repeat steps 2 to 3 until the established equivalent calculation model can reproduce its results under the same working conditions of the body-in-white.

[0111] Specifically, the stiffness of the equivalent calculation model can be calculated by referring to the following formula (1) according to the bending and torsional stiffness calculation formulas:

[0112]

[0113] Among them, w i is the applied load, unit: N; d iis the bending deflection at the loading point, unit: mm; M is the moment, unit: N·m; θ is the rotation angle, unit: °. After calculation, the bending stiffness of the rear floor is 1318.26N / MM, and the torsional stiffness is 9426.65NM / °.

[0114] Optionally, the step 105 includes: establishing an extended design domain model according to the equivalent simulation analysis result, taking the rear floor side and floor plane area as the design area, and applying a draft constraint in the draft direction of the die-casting structure.

[0115] In the embodiment of the present application, the equivalent simulation analysis results of the rear floor include its displacement response, stress distribution and stiffness performance under bending and torsion conditions, etc. These analysis results provide direct feedback on the structural performance of the rear floor and are the basis for subsequent optimization design.

[0116] Based on the results of equivalent simulation analysis, the areas in the rear floor structure with insufficient performance or in need of optimization are identified, and these areas will serve as the focus of the extended design domain. The extended design domain is not limited to the rear floor itself, but may also include other components or structures that are connected to or interact with it. In the finite element analysis software or a dedicated optimization design platform, an extended design domain model of the rear floor and its related structures is established based on the identified extended design domain. This model should be able to accurately reflect the geometry, material properties, and connection methods of the rear floor and its surrounding structures.

[0117] In the extended design domain model, the design area is refined, and the side and floor plane areas of the rear floor are clearly selected as the focus of optimization. These areas are usually the parts of the rear floor structure that are subject to greater forces, more obvious deformations, or prone to problems during the manufacturing process. In the design area, according to the optimization goals (such as increasing stiffness, reducing weight, etc.), set adjustable design variables, such as material thickness, shape, and rib layout.

[0118] Die casting is a manufacturing process that injects molten metal into a mold and solidifies it into shape. During the die casting process, the draft direction of the mold has an important impact on the forming quality and demolding difficulty of the product. Draft constraints refer to certain angles or shape restrictions that need to be followed in mold design or product design in order to ensure that the product can be smoothly ejected from the mold.

[0119] In the extended design domain model, according to the characteristics and requirements of the die-casting process, draft constraints are imposed on the draft direction of the die-cast structures of the rear floor (such as ribs, protrusions, etc.). This usually means that it is necessary to ensure that these structures have a certain inclination angle or smooth transition in the draft direction to avoid defects such as cracks and scratches during the demolding process.

[0120] Reference Figure 6 , is the schematic diagram of the draft direction of the rear floor, Figure 7Schematic diagram of the finite element calculation model of the design domain.

[0121] When applying draft constraints, it is necessary to weigh their impact on the rear floor structure performance (such as stiffness and strength) and manufacturing processability (such as mold design and demolding difficulty). It may be necessary to perform multiple iterative designs and simulation analyses to find the best design solution that meets performance requirements and manufacturing processability.

[0122] Optionally, step 106 includes: optimizing the optimization model by using a linear weighted method based on the SIMP method, applying optimization constraints to the equivalent model in combination with the casting process, presetting different weighting schemes, optimizing the connectivity and rationality of the structure, and determining the weighting coefficient scheme based on the change in the weighted flexibility of the structure.

[0123] In the present application embodiment, SIMP method is a commonly used topology optimization method, by introducing a virtual material model with a penalty factor, the structural optimization problem is converted into an optimization problem of material distribution. In SIMP method, each unit in the design domain is assigned a relative density (or pseudo-density), which varies between 0 and 1, indicating the presence or absence of material or how much. Linear weighted method is a multi-objective optimization technique, by assigning weights to different optimization targets (such as weight, stiffness, flexibility, etc.), they are combined into a single objective function for optimization. Here, linear weighted method is used to combine SIMP method to consider multiple performance indicators simultaneously during the optimization process. According to the goal of the optimization model (such as minimizing the weight of the structure while maintaining sufficient stiffness), weights are assigned to different performance indicators (such as weight, flexibility). Use SIMP method as the basis of the optimization algorithm, combine linear weighted method to construct objective function, and find the optimal material distribution through iterative calculation.

[0124] Specifically, the topology optimization problem of the structure is defined as follows: The optimization objective is Where C is the structural flexibility N·mm, ω is the weight coefficient. The optimization constraint is f>f min , f is the fundamental frequency of the structure, f min is the target fundamental frequency, is the unit volume, is the target volume.

[0125] Different weighting schemes are preset, including the bending condition weight coefficient ω1 and the torsion condition weight coefficient ω2. The topology optimization results obtained from different schemes are analyzed, and the final weighting coefficient scheme is determined by comprehensively considering the connectivity, rationality and change in the weighted flexibility of the optimized structure.

[0126] The casting process has specific requirements for the shape, size and material distribution of the structure, such as draft angle, wall thickness uniformity, avoiding islands, etc. These constraints need to be considered in the optimization process to ensure that the optimized structure can be cast smoothly. In the optimization model, corresponding constraints are imposed on the equivalent model according to the requirements of the casting process. These include limiting the material distribution in certain areas, ensuring the connectivity of the structure, avoiding too small feature sizes, etc.

[0127] Reference Figure 8 Different weighting schemes will affect the optimization results, because the weight distribution determines the relative importance of each performance indicator in the optimization process. Before starting the optimization, a variety of different weighting schemes are preset based on design experience and target requirements. These schemes may focus on different performance indicators, such as paying more attention to weight reduction, paying more attention to stiffness improvement, or seeking a balance between the two.

[0128] Connectivity refers to the degree of connection between the various parts of the structure. Reasonable connectivity can ensure the integrity and stability of the structure. Reasonableness involves whether the geometric shape, material distribution, etc. of the structure meet the actual manufacturing and use requirements. During the optimization process, it is necessary to pay attention to and optimize the connectivity and rationality of the structure to avoid unreasonable structural forms or manufacturing difficulties. Structural weighted flexibility is an indicator of structural stiffness. Through optimization, the flexibility of the structure can be reduced and the stiffness can be increased. During the optimization process, it is necessary to pay attention to the change in the weighted flexibility of the structure to ensure that the optimized structure has an improvement in stiffness.

[0129] Optimize each weighting scheme and evaluate the effect of the optimization results. This includes comparing the performance indicators of the structure weight, stiffness, flexibility, etc. under different schemes, and considering factors such as manufacturing processability and cost. According to the evaluation results, the optimal weighting coefficient scheme is selected as the final design scheme. This scheme should be able to meet the performance requirements while also meeting the considerations of manufacturing processability and cost control.

[0130] For example, refer to Fig. 9 It is a schematic side view effect diagram of a lightweight design solution obtained by obtaining a design solution of a die-casting vehicle body structure provided by the present application, Fig.10 This is a schematic diagram of an overhead view of a lightweight design solution obtained by a design scheme acquirer for a die-cast body structure.

[0131] Based on the same inventive concept, the embodiment of the present application also provides a design solution acquisition device for die-cast body structural parts for implementing the design solution acquisition method for die-cast body structural parts involved in the above. The implementation solution for solving the problem provided by the device is similar to the implementation solution recorded in the above method, so the specific limitations in the embodiments of the design solution acquisition device for one or more die-cast body structural parts provided below can refer to the limitations of the design solution acquisition method for die-cast body structural parts above, and will not be repeated here.

[0132] In an exemplary embodiment, Fig.11 As shown, a design scheme acquisition device 20 for a die-cast vehicle body structural component is provided, comprising:

[0133] An acquisition module 201 is used to analyze the main design area of ​​the integral die-cast aluminum alloy material;

[0134] Performing a tensile test on the main design area of ​​the one-piece die-cast aluminum alloy material to obtain mechanical property parameters;

[0135] Establish the BIW finite element model and perform bending and torsional stiffness simulation calculation to obtain the BIW bending and torsional stiffness results;

[0136] Used to establish equivalent boundary conditions for the rear floor structure based on the BIW bending and torsional stiffness results, and perform equivalent simulation analysis to obtain equivalent simulation analysis results;

[0137] Used to establish an optimization model of the rear floor structure according to the equivalent simulation analysis results;

[0138] Performing topology optimization on the optimization model to obtain a topology optimization result;

[0139] A design module 202, performing a lightweight design on the rear floor structure based on the topology optimization result;

[0140] Perform performance verification on the lightweight rear floor structure;

[0141] The lightweight designed rear floor structure is adjusted according to the verification result.

[0142] Optionally, the acquisition module 201 is further used to:

[0143] The location, original structure and overlapping surfaces of the one-piece die-cast floor were analyzed to determine the main design areas.

[0144] Optionally, the acquisition module 201 is further used to:

[0145] A tensile test is carried out in accordance with preset standard regulations to obtain the mechanical property parameters of the one-piece die-cast aluminum alloy material as parameter input for finite element analysis and topology optimization calculations.

[0146] Optionally, the acquisition module 201 is further used to:

[0147] A finite element model of the body-in-white is established, the model is meshed using quadrilateral shell elements, and a bending and torsional stiffness simulation calculation of the body-in-white level is performed according to preset standard regulations to obtain the body-in-white bending and torsional stiffness results.

[0148] Optionally, the acquisition module 201 is further used to:

[0149] Based on the bending and torsional stiffness results of the body in white, equivalent boundary conditions are established for the rear floor structure, and equivalent simulation analysis is carried out. The displacement responses in the equivalent simulation analysis results of the rear floor bending and torsional working conditions are extracted, and the bending and torsional stiffness of the rear floor structure are calculated as equivalent simulation analysis results.

[0150] Optionally, the acquisition module 201 is further used to:

[0151] An extended design domain model is established according to the equivalent simulation analysis results, and the side surface and the floor plane area of ​​the rear floor are used as the design area, and draft constraints are applied in the draft direction of the die-casting structure.

[0152] Optionally, the design module 202 is further used to:

[0153] The optimization model is optimized by a linear weighted method based on the SIMP method. The optimization constraints are imposed on the equivalent model in combination with the casting process. Different weighting schemes are preset, and the connectivity and rationality of the optimized structure and the change in the weighted flexibility of the structure are used to determine the weighting coefficient scheme.

[0154] The embodiment of the present application deeply analyzes the main design areas of the one-piece die-cast aluminum alloy material and obtains its mechanical property parameters, establishes a finite element model of the body-in-white to perform bending and torsional stiffness simulation calculations, establishes equivalent boundary conditions for the rear floor structure and performs equivalent simulation analysis, and then establishes an optimization model to perform topology optimization, ultimately achieving a lightweight design, and performing performance verification to ensure that the design meets the requirements, thereby achieving the multiple effects of lightweight, high performance and reliability at the technical level, which not only improves design efficiency but also reduces manufacturing costs.

[0155] In an exemplary embodiment, a computer device is provided. The computer device may be a server or a terminal. The internal structure diagram thereof may be as follows: Fig.12As shown. The computer device includes a processor, a memory, an input / output interface (Input / Output, referred to as I / O) and a communication interface. Among them, the processor, the memory and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store design scheme acquisition data for die-cast body structural parts. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a method for acquiring a design scheme for a die-cast body structural part is implemented.

[0156] Those skilled in the art will understand that Fig.12 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0157] In an exemplary embodiment, a computer device is further provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps in the above-mentioned method embodiments when executing the computer program.

[0158] In an exemplary embodiment, a computer-readable storage medium is provided, storing a computer program, and when the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0159] In an exemplary embodiment, a computer program product is provided, including a computer program, and when the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0160] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0161] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM may be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0162] The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. The non-relational database may include a distributed database based on blockchain, etc., but is not limited thereto. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but is not limited thereto.

[0163] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0164] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A method for obtaining a design scheme for a die-cast vehicle body structural component, characterized in that: The method for obtaining the design scheme of the die-cast vehicle body structural part comprises: Analyze the main design areas of one-piece die-cast aluminum alloy materials; Performing a tensile test on the main design area of ​​the one-piece die-cast aluminum alloy material to obtain mechanical property parameters; Establish the BIW finite element model and perform bending and torsional stiffness simulation calculation to obtain the BIW bending and torsional stiffness results; Based on the BIW bending and torsional stiffness results, equivalent boundary conditions are established for the rear floor structure, and equivalent simulation analysis is performed to obtain equivalent simulation analysis results; Establishing an optimization model of the rear floor structure according to the equivalent simulation analysis results; Performing topology optimization on the optimization model to obtain a topology optimization result; Performing a lightweight design on the rear floor structure based on the topology optimization result; Perform performance verification on the lightweight rear floor structure; The lightweight designed rear floor structure is adjusted according to the verification result.

2. The method for obtaining a design solution for a die-cast vehicle body structural component according to claim 1, characterized in that: The steps of analyzing the main design areas of the one-piece die-casting aluminum alloy material include: The location, original structure and overlapping surfaces of the one-piece die-cast floor were analyzed to determine the main design areas.

3. The method for obtaining a design solution for a die-cast vehicle body structural component according to claim 2, characterized in that: The step of performing a tensile test on the main design area of ​​the one-piece die-cast aluminum alloy material to obtain mechanical property parameters comprises: A tensile test is carried out in accordance with preset standard regulations to obtain the mechanical property parameters of the one-piece die-cast aluminum alloy material as parameter input for finite element analysis and topology optimization calculations.

4. The method for obtaining a design solution for a die-cast vehicle body structural component according to claim 2, characterized in that: The steps of establishing a BIW finite element model and performing a bending-torsion stiffness simulation calculation to obtain a BIW bending-torsion stiffness result include: A finite element model of the body-in-white is established, the model is meshed using quadrilateral shell elements, and a bending and torsional stiffness simulation calculation of the body-in-white level is performed according to preset standard regulations to obtain the body-in-white bending and torsional stiffness results.

5. The method for obtaining a design solution for a die-cast vehicle body structural component according to claim 1, characterized in that: The steps of establishing equivalent boundary conditions for the rear floor structure based on the BIW bending and torsional stiffness results and performing equivalent simulation analysis to obtain equivalent simulation analysis results include: Based on the bending and torsional stiffness results of the body in white, equivalent boundary conditions are established for the rear floor structure, and equivalent simulation analysis is carried out. The displacement responses in the equivalent simulation analysis results of the rear floor bending and torsional working conditions are extracted, and the bending and torsional stiffness of the rear floor structure are calculated as equivalent simulation analysis results.

6. The method for obtaining a design solution for a die-cast vehicle body structural component according to claim 1, characterized in that: The step of establishing the optimization model of the rear floor structure according to the equivalent simulation analysis results comprises: An extended design domain model is established according to the equivalent simulation analysis results, and the side surface and the floor plane area of ​​the rear floor are used as the design area, and draft constraints are applied in the draft direction of the die-casting structure.

7. The method for obtaining a design solution for a die-cast vehicle body structural component according to claim 6, characterized in that: The step of performing topology optimization on the optimization model to obtain a topology optimization result comprises: The optimization model is optimized by a linear weighted method based on the SIMP method. The optimization constraints are imposed on the equivalent model in combination with the casting process. Different weighting schemes are preset, and the connectivity and rationality of the optimized structure and the change in the weighted flexibility of the structure are used to determine the weighting coefficient scheme.

8. A design scheme acquisition device for die-casting vehicle body structural parts, characterized in that: The design scheme acquisition device of the die-cast vehicle body structural part comprises: Acquisition module for analyzing the main design areas of one-piece die-cast aluminum alloy materials; Performing a tensile test on the main design area of ​​the one-piece die-cast aluminum alloy material to obtain mechanical property parameters; Establish the BIW finite element model and perform bending and torsional stiffness simulation calculation to obtain the BIW bending and torsional stiffness results; Used to establish equivalent boundary conditions for the rear floor structure based on the BIW bending and torsional stiffness results, and perform equivalent simulation analysis to obtain equivalent simulation analysis results; Used to establish an optimization model of the rear floor structure according to the equivalent simulation analysis results; Performing topology optimization on the optimization model to obtain a topology optimization result; A design module, performing a lightweight design on the rear floor structure based on the topology optimization result; Perform performance verification on the lightweight rear floor structure; The lightweight designed rear floor structure is adjusted according to the verification result.

9. A computer device comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the method for obtaining a design solution for a die-cast vehicle body structural part according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method for obtaining a design solution for a die-cast vehicle body structural component according to any one of claims 1 to 7 are implemented.

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