3D simulation of prefabricated body layup method

Abstract

This invention provides a 3D simulation method and system for precast body layup, relating to the field of composite material precast body molding simulation technology. Based on the modeling data of the target component, a standard three-dimensional model of the target component is constructed. Layup parameters of the target component are configured. The standard three-dimensional model is then adaptively meshed into layers to obtain a layered simulation model. Based on the layup parameters, the layered simulation model undergoes layup force-thermal coupling simulation processing to obtain simulation data. Defects are identified based on the simulation data to obtain defect identification results. Based on the defect identification results, the layup parameters are iteratively corrected to obtain corrected parameters. When the simulation data corresponding to the corrected parameters meets standard production indicators, the output layup scheme can be used for thermo-mechanical coupling simulation of the precast body, improving the efficiency of determining production process parameters.

Description

Technical Field

[0001] This invention relates to the field of composite material preform molding simulation technology, and in particular to a 3D simulation method for preform layup. Background Technology

[0002] Carbon-carbon composite materials possess excellent high-temperature stability, thermal shock resistance, and structural strength, making them a core material for the preparation of thermal field systems in high-end equipment such as photovoltaic single-crystal furnaces and semiconductor high-temperature equipment. Typical components include irregularly shaped, high-curvature structures such as crucibles, crucible supports, and annular insulation cylinders. Prefabrication layup is a key process that determines the molding accuracy, interlayer bonding strength, high-temperature deformation, and service life of carbon-carbon thermal field components. Layup path planning, tension control, and compaction uniformity directly affect the densification effect and structural reliability of the components.

[0003] Existing technologies typically employ two-dimensional planar static simulation to simulate the layup of carbon-carbon composite preforms. This approach is only suitable for regular flat components and suffers from poor geometric accuracy when dealing with irregularly shaped, high-curvature components such as crucibles and insulation cylinders. The large discrepancy between the model and the actual product can easily lead to layup path failure. Furthermore, traditional technologies only consider room-temperature mechanical parameters without coupling key effects such as thermal stress, fiber thermal shrinkage, and interlayer thermal friction during the high-temperature densification process. This makes it impossible to realistically simulate high-temperature molding deformation, resulting in significant discrepancies between simulation results and actual production. Process iteration relies entirely on manual experience, and the densification cycle for carbon-carbon materials is lengthy, leading to a large waste of carbon fiber raw materials and production capacity. In addition, the instability of manual adjustment accuracy results in poor molding consistency and low yield.

[0004] Therefore, how to perform thermo-mechanical coupling simulation of prefabricated structures and improve the efficiency of determining production process parameters has become an urgent problem to be solved. Summary of the Invention

[0005] This invention provides a 3D simulation method for prefabricated body layup, which can perform thermo-mechanical coupling simulation of prefabricated bodies and improve the efficiency of determining production process parameters.

[0006] A first aspect of the present invention provides a 3D simulation method for prefabricated body layup, comprising: Based on the modeling data of the target component, a standard three-dimensional model of the target component is constructed, the plying parameters of the target component are configured, and the standard three-dimensional model is subjected to adaptive surface mesh layering to obtain a layered simulation model. Based on the ply parameters, the layered simulation model is subjected to ply force-thermal coupling simulation processing to obtain simulation data; Defects are identified based on the simulation data to obtain defect identification results. The layup parameters are then iteratively corrected based on the defect identification results to obtain corrected parameters. When the simulation data corresponding to the corrected parameters meets the standard production indicators, the layup scheme is output.

[0007] Optionally, in one possible implementation of the first aspect, the adaptive surface mesh layering of the standard three-dimensional model to obtain a layered simulation model includes: The standard 3D model is meshed using an adaptive meshing algorithm to obtain a 2D meshed 3D model. The 2D mesh 3D model is filled with a volume mesh to obtain a 3D mesh 3D model; Based on the shape characteristics and ply parameters of the target component, multiple spatial slice surfaces are generated along the normal direction of the target component; The 3D mesh model is cut based on the spatial slicing surface and geometric intersection algorithm to obtain an initial layered model. The initial hierarchical model is processed by independent data segmentation to generate a hierarchical simulation model.

[0008] Optionally, in one possible implementation of the first aspect, the step of meshing the standard 3D model based on an adaptive meshing algorithm to obtain a 2D meshed 3D model includes: Identify the boundary surfaces of a standard 3D model and extract geometric patches, then calculate the principal curvature of each geometric patch based on a differential geometry algorithm; The comparison is performed between the principal curvature and the preset curvature threshold to obtain the comparison result, and the mesh node density of the corresponding geometric patch is determined based on the comparison result. Based on the stated grid node density, a topological mesh is generated on the boundary surface to obtain a 2D mesh 3D model.

[0009] Optionally, in one possible implementation of the first aspect, the step of cutting the 3D mesh model based on the spatial slice surface and geometric intersection algorithm to obtain an initial layered model includes: Based on the geometric intersection algorithm, the spatial slice surface is passed through the mesh cells of the 3D mesh model to obtain intersecting cells; The intersecting cells are reconstructed into mesh cells to generate multiple reconstructed mesh cells. The reconstructed mesh cells are then labeled with layer domain labels to obtain an initial hierarchical model with labeled mesh cells.

[0010] Optionally, in one possible implementation of the first aspect, the step of independently processing the data segmentation of the initial hierarchical model to generate a hierarchical simulation model includes: The common nodes located on each spatial slice surface in the initial layered model are split and labeled to obtain contact pairs; The interlayer friction loss formula is retrieved and correlated with the data of each contact pair to obtain a layered simulation model.

[0011] Optionally, in one possible implementation of the first aspect, the step of performing ply stress-thermal coupling simulation processing on the layered simulation model based on the ply parameters to obtain simulation data includes: A layer-by-layer laying simulation is performed using a virtual laying tool controlled by layup parameters to obtain the mechanical layup response and initial layup offset of the current layer. The precast body of the target component is subjected to heating simulation based on time-varying temperature load, and the thermodynamic coupling response and fiber placement offset compensation amount are obtained in real time at each temperature. The simulation data are obtained based on the mechanical layup response, thermodynamic coupling response, and fiber layup offset compensation.

[0012] Optionally, in one possible implementation of the first aspect, the step of performing layer-by-layer layup simulation based on the ply parameter control virtual layup tool to obtain the mechanical ply response and initial ply offset of the current layup layer includes: The virtual laying tool is controlled to move along a preset three-dimensional trajectory on the mesh surface of the current laying layer based on the laying travel rate and interlayer compaction pressure, and the fiber laying tension stress of the mesh nodes is extracted based on the solver. By inputting the fiber layup tension stress and elastic modulus into the fiber tensile deformation formula, the tensile deformation strain of the carbon fiber layup is obtained. Obtain the actual spatial coordinates and preset trajectory coordinates of the current marked grid cell, perform displacement offset calculations, and obtain the initial ply offset. The in-plane transverse shear stress between the updated layup layer and the adjacent layup layer is calculated based on the interlayer activation mechanism. The mechanical response of the carbon fiber layup was obtained based on the tensile strain and in-plane transverse shear stress of the carbon fiber layup.

[0013] Optionally, in one possible implementation of the first aspect, the step of calculating and updating the in-plane transverse shear stress between the ply and adjacent ply according to the interlayer activation mechanism includes... A new layer of mesh is laid to obtain an updated layer. Based on the updated layer, the contact pairs corresponding to the adjacent layers are activated, and the interlayer compaction pressure of the current updated layer and the interlayer slippage of the fibers corresponding to the adjacent layers are obtained. The interlayer friction force is calculated by inputting the interlayer compaction pressure, fiber interlayer slip, friction coefficient and roughness correction coefficient into the interlayer friction loss formula. The in-plane transverse shear stress is obtained based on the ratio of the interlayer friction of the fibers to the area of ​​the mesh unit.

[0014] Optionally, in one possible implementation of the first aspect, the real-time acquisition of the thermodynamic coupling response and fiber placement offset compensation at each temperature node includes: After determining the layup simulation, the preform of the target component is heated based on the time-varying temperature load, and the forming temperature difference is obtained based on the temperature difference between the current temperature and the initial temperature. The friction coefficient and elastic modulus are switched numerically based on the current temperature to obtain the current friction coefficient and current elastic modulus; The thermal friction force is calculated based on the current friction coefficient to obtain the interlayer friction force of the thermal fibers. Based on the ratio of the interlayer friction force of the thermal fibers to the area of ​​the mesh unit, the transverse shear stress in the thermal surface is obtained. The transient thermal stress is obtained, and the transient thermal stress and the current elastic modulus are input into the fiber tensile deformation formula to obtain the thermal deformation strain of the carbon fiber layup. The thermodynamic coupling response is obtained based on the transverse shear stress in the hot surface and the thermal deformation strain of the carbon fiber layup. The initial offset, thermal shrinkage coefficient, laying error correction coefficient, and molding temperature difference are input into the high-temperature displacement compensation formula to obtain the fiber laying offset compensation amount.

[0015] Optionally, in one possible implementation of the first aspect, the step of identifying defects based on the simulation data to obtain defect identification results, and iteratively correcting the layup parameters based on the defect identification results to obtain corrected parameters, includes: The simulation data is compared one by one based on the preset standard molding index to obtain the defect identification results, which include no defect results, minor defect results, general defect results and serious defect results. When the defect identification result is determined to be a general defect result, the laying travel rate and interlayer compaction pressure are finely adjusted to obtain the corrected laying travel rate and corrected interlayer compaction pressure. When the defect identification result is determined to be a severe defect, the layup angle and fiber tension are iterated again to obtain the corrected layup angle and corrected fiber tension; The correction parameters are obtained by correcting the laying travel rate, interlayer compaction pressure, laying angle, and fiber tension.

[0016] A second aspect of the present invention provides an electronic device, comprising: a memory, a processor, and a computer program, wherein the computer program is stored in the memory, and the processor executes the computer program to perform the methods described in the first aspect of the present invention and various possible methods related to the first aspect.

[0017] A third aspect of the present invention provides a storage medium storing a computer program, which, when executed by a processor, is used to implement the first aspect of the present invention and various methods possibly involved in the first aspect.

[0018] The beneficial effects of this invention are as follows: 1. This invention can adaptively mesh and layer the standard 3D model of a target component to construct a layered simulation model, thereby improving the adaptability of the layered simulation model to the target component. Specifically, this invention can perform 3D modeling based on the full-size parameters of the target component, and adaptively mesh and layer the 3D model based on the principal curvature to construct a layered simulation model with isolated data between layers that can independently carry simulation information, thus improving the accuracy of the model simulation.

[0019] 2. This invention can complete the full-process mechanical-thermal coupling simulation at both room temperature and high temperature, improving the simulation accuracy of the precast forming of the target component. Specifically, this invention can construct a mechanical-thermal coupling simulation system covering the entire process of room temperature laying and high temperature carbonization based on a carbon fiber orthotropic constitutive model and equipped with three exclusive formulas for fiber tensile deformation, interlaminar friction loss, and high temperature displacement compensation. It can dynamically simulate real physical behaviors such as fiber laying, interlaminar bonding, compaction deformation, thermal stress transmission, and thermal shrinkage offset. It completes the mechanical response calculation of the layup at room temperature and realizes the adaptive switching of material parameters with temperature, transient thermal stress solution, thermally induced shear stress calculation and thermal deformation strain output at high temperature. Furthermore, it corrects the layup offset in real time through the high temperature displacement compensation formula, improving the matching degree between the simulation results and the actual forming.

[0020] 3. This invention can automatically iterate and optimize process parameters without having to conduct multiple lengthy carbonization trial productions, thereby reducing the R&D cycle and improving R&D efficiency. Attached Figure Description

[0021] Figure 1 A flowchart of a 3D simulation prefabrication layup method provided by the present invention; Figure 2 A flowchart for determining a hierarchical simulation model provided by the present invention; Figure 3 A flowchart illustrating the simulation of a hierarchical simulation model provided by this invention; Figure 4 This is a schematic diagram of the hardware structure of an electronic device provided by the present invention. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] The technical solution of the present invention will be described in detail below with reference to specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0024] like Figure 1 As shown, the present invention provides a 3D simulation method for prefabricated body layup, comprising: S1. Construct a standard three-dimensional model of the target component based on the modeling data of the target component, configure the layup parameters of the target component, and perform adaptive surface mesh layering on the standard three-dimensional model to obtain a layered simulation model.

[0025] It should be noted that existing carbon-carbon composite thermal field components typically employ two-dimensional planar modeling and uniform mesh generation, resulting in significant geometric deviations between the simulation model and the actual component. This affects the layup path. Furthermore, existing simulation techniques usually only consider room-temperature mechanical parameters and do not simulate the high-temperature carbonization process of carbon-carbon materials. Consequently, they cannot simulate the deformation state of the preform during subsequent high-temperature processes, leading to significant discrepancies between simulation results and actual molding, thus impacting preform molding efficiency. Therefore, this invention can construct a corresponding standard three-dimensional model based on the required three-dimensional design drawings and dimensional parameters of the target carbon-carbon thermal field component. It also automatically matches and inputs specific process parameters based on the high-temperature mechanical performance requirements of the target carbon-carbon thermal field component, such as flexural strength, thermal conductivity, high-temperature stability, and carbon fiber raw material properties. This allows for adaptive surface mesh layering of the standard three-dimensional model, resulting in a layered simulation model. This facilitates subsequent simulation and improves the efficiency of determining production parameters.

[0026] Understandably, when constructing a standard 3D model of the target component, a full-size 3D solid model can be built using SolidWorks or UG based on the 3D design drawings and dimensional parameters of the target component. Sub-millimeter level fine fitting is then performed on high-curvature surfaces, edge chamfers, and hollow structures. Surface completion algorithms are used to repair minor damage and topological defects in the model. Finally, the model accuracy is calibrated to a preset range, such as ±0.02mm, and a standardized 3D model is output. The layup parameters of the target component are preset and matched according to the high-temperature mechanical performance requirements of the target component, such as flexural strength, thermal conductivity, high-temperature stability, and carbon fiber raw material properties. These layup parameters may include fiber tension threshold of 5–35N, single-layer layup thickness of 0.1–0.8mm, layup travel rate of 5–25mm / s, interlayer compaction pressure of 0.2–1.5MPa, and curing pre-temperature of 40–80℃.

[0027] It is not difficult to understand that, as Figure 2 As shown, in order to ensure that each mesh layer can independently carry simulation data and avoid crosstalk between layers, the standard 3D model can be divided into mesh layers to obtain a layered simulation model with multiple meshes. This facilitates the acquisition of corresponding simulation data in the subsequent simulation process and improves the accuracy of the final output layering scheme.

[0028] Among them, the target component is the target carbon-carbon thermal field component to be produced, such as the crucible, crucible support, and insulation cylinder. The modeling data is the reference data for constructing the three-dimensional model of the target component, such as the three-dimensional design drawings and dimensional parameters of the target component. The standard three-dimensional model is the three-dimensional model of the target component. The layup parameters are the layup technical parameters for constructing the prefabricated target component. The layup parameters may include fiber tension threshold, single-layer layup thickness, layup travel rate, interlayer compaction pressure, and curing pre-temperature. The layered simulation model is the model for simulating the layup of the prefabricated body after meshing the standard three-dimensional model.

[0029] In some embodiments, the specific implementation of step S1 (the adaptive surface mesh layering of the standard three-dimensional model to obtain a layered simulation model) includes: S11, The standard 3D model is meshed based on an adaptive meshing algorithm to obtain a 2D mesh 3D model.

[0030] It should be noted that the essence of mesh generation is to discretize a standard 3D model, i.e., a continuous geometric entity, into a finite set of regular geometric units. Since the shapes of target components vary, an appropriate mesh generation algorithm can be selected based on the shape of the target component. That is, adaptive mesh generation algorithms can be adaptive tetrahedral mesh generation algorithms or adaptive hexahedral mesh generation algorithms. When the target component is a regular curved surface thermal field component, such as a cylindrical insulation cylinder, an adaptive hexahedral mesh generation algorithm can be used to improve computational efficiency. When meshing a standard 3D model, different mesh densities can be set for different curvature regions. At the same time, layer cutting is completed according to the number of layers designed for the prefabricated body, ensuring that each layer of mesh independently carries simulation data and avoiding crosstalk between layers, resulting in a layered simulation model.

[0031] It is understandable that adaptive mesh generation algorithms are algorithms that adaptively mesh standard 3D models, such as adaptive tetrahedral mesh generation algorithms and adaptive hexahedral mesh generation algorithms. 2D mesh 3D models are 3D models with topological surface meshes generated on the surface of 3D models, which facilitates subsequent mesh filling and layer cutting.

[0032] In some embodiments, the specific implementation of step S11 (the step of meshing the standard 3D model based on an adaptive meshing algorithm to obtain a 2D mesh 3D model) includes: S111 identifies the boundary surfaces of the standard 3D model and extracts geometric patches, then calculates the principal curvature of each geometric patch based on a differential geometry algorithm.

[0033] It is understandable that the outer boundary surface of the model can be identified using existing mature technologies such as topological relationship determination. The boundary surface can be divided into several independent geometric patches using methods such as surface continuity segmentation, normal vector angle threshold segmentation, or curvature abrupt change segmentation. For each geometric patch, the first and second order partial derivatives can be calculated using parametric surface differential geometry algorithms to solve for the first and second fundamental forms of the surface, thereby obtaining the principal curvatures corresponding to each geometric patch.

[0034] It is easy to understand that by calculating the principal curvature of each geometric facet, the outer surface of the standard 3D model can be meshed. Different mesh densities are created for geometric facets with different principal curvatures, so that the meshes built in the high curvature feature regions are denser and smaller in size. This helps to ensure that the geometric features of local sharp corners and curved surfaces are not distorted or lost, and prevents the path failure problem caused by geometric approximation in traditional simulations.

[0035] In this model, the boundary surface is the outer surface of the standard 3D model, the geometric patch is a patch region with different geometric features on the boundary surface, and the principal curvature is the curvature of the geometric patch.

[0036] S112, compare the principal curvature with the preset curvature threshold to obtain the comparison result, and determine the mesh node density of the corresponding geometric patch based on the comparison result.

[0037] Understandably, the principal curvature is compared with a preset curvature threshold to obtain the comparison result, which in turn determines the mesh size of the corresponding geometric patch. That is, the mesh node density is obtained based on the ratio of the area of ​​the geometric patch to the mesh size. For example, when the principal curvature of a region is greater than the preset curvature threshold, the region corresponding to the geometric patch can be determined to be a high curvature feature region. In order to make the discretized mesh fit the real arc surface and avoid geometric distortion, the spacing of the mesh seeds in the region is automatically shortened. For example, the mesh size of the corresponding geometric patch can be determined to be 0.2mm. That is, the mesh node density is obtained based on the ratio of the area of ​​the geometric patch to the mesh size. When the principal curvature is less than or equal to the preset curvature threshold, the region corresponding to the geometric patch can be determined to be a flat feature region, and the mesh size of the corresponding geometric patch can be determined to be 1mm.

[0038] It is easy to understand that the mesh size for high curvature surface regions is 0.2 to 0.5 mm, and the mesh size for flat regions is 1 to 2 mm, so that the mesh node density can be determined according to the mesh size, and the mesh can be generated on the boundary surface of the standard 3D model in the future.

[0039] The preset curvature threshold is a pre-set threshold for determining the characteristics of a geometric patch region. It can be manually preset, for example, 0.5mm. - ¹, The comparison result is the judgment result of numerical comparison between the main curvature and the preset curvature threshold. For example, it can include high curvature feature areas and flat areas. The seed density is the density of the mesh generated in the geometric patch area.

[0040] S113, Generate a topological mesh on the boundary surface according to the mesh node density to obtain a 2D mesh 3D model.

[0041] Understandably, triangular meshes can be filled on the boundary surface using the Delaunay triangulation algorithm or the forward propagation method based on the mesh node density. For example, mesh nodes can be placed on the geometric contour lines and outer surfaces of a standard 3D model according to a preset length, thereby obtaining a 3D model with a 2D mesh on the model surface.

[0042] S12, fill the 2D mesh of the 3D model with a volume mesh to obtain a 3D mesh model.

[0043] Understandably, when using an adaptive tetrahedral meshing algorithm, the volume mesh filling of a 2D mesh 3D model can be achieved by using the surface triangular mesh as a base and pushing it into the interior of the model entity, continuously searching for or calculating the optimal spatial nodes of the internal cavities, thereby connecting them into a dense array of tetrahedral mesh units. When using an adaptive hexahedral meshing algorithm, the volume mesh filling of a 2D mesh 3D model can be achieved by using a map mapping method or a sweeping method to stretch or sweep the surface quadrilateral mesh through the entire model entity along the thickness or diameter direction of the target component's corresponding 3D model, forming a solid hexahedral block, thus obtaining a 3D mesh 3D model.

[0044] Among them, the 3D mesh three-dimensional model is a three-dimensional model with 3D solid mesh units.

[0045] S13, Generate multiple spatial slice surfaces along the normal direction of the target component based on the shape characteristics and ply parameters of the target component.

[0046] Understandably, based on the shape characteristics of the target component, such as curved or planar features, multiple spatial slice surfaces are virtually created in space along the normal direction and thickness stacking direction of the target component, with the single-layer layup thickness in the layup parameters as the interval. The number of spatial slice surfaces is the same as the preset number of layers in the layup parameters, such as 12 layers.

[0047] Among them, the shape feature is the shape feature of the target component, the normal direction is the defense line of the target component corresponding to the thickness stacking, and the spatial slice surface is the slice of the 3D mesh 3D model in 3D space.

[0048] S14, the 3D mesh model is cut based on the spatial slicing surface and geometric intersection algorithm to obtain the initial layered model.

[0049] Understandably, the geometric intersection algorithm is used to cut the spatial slice surface into a 3D mesh model to obtain an initial layered model, so that the layered simulation model can be obtained by independent processing of data segmentation for prefabricated body layering simulation.

[0050] Among them, the geometric intersection algorithm is an existing algorithm for cutting the model, which will not be elaborated here. The initial layered model is a layered model that only physically divides the 3D mesh three-dimensional model entities and performs independent data processing.

[0051] In some embodiments, the specific implementation of step S14 (cutting the 3D mesh model based on the spatial slice surface and geometric intersection algorithm to obtain an initial layered model) includes: S141, based on the geometric intersection algorithm, the spatial slice surface passes through the mesh cells of the 3D mesh model to obtain intersecting cells.

[0052] It is understandable that when a spatial slice surface passes through the mesh cells of a 3D mesh model, it will split some of the original mesh cells in two. The geometric intersection algorithm can automatically generate new nodes on the intersection line of the slice surface and reconstruct the cut mesh cells into reconstructed mesh cells that conform to the boundary.

[0053] Intersecting elements are mesh elements where spatial slices intersect with the 3D mesh model.

[0054] S142, the intersecting units are reconstructed into mesh units to generate multiple reconstructed mesh units, and the reconstructed mesh units are labeled with layer domain labels to obtain an initial hierarchical model with labeled mesh units.

[0055] Understandably, in order to keep each layer of the mesh in the layered simulation model intact, the mesh elements that will be cut at each location can be reconstructed to generate reconstructed mesh elements, and the reconstructed mesh elements of different layers can be labeled. For example, the reconstructed mesh elements of the first layer in the initial layered model are labeled as the first layer, and the reconstructed mesh elements of the second layer are labeled as the second layer, thus obtaining an initial layered model with labeled mesh elements.

[0056] Among them, reconstructing the mesh cell involves reconstructing the mesh cells divided into different layers to obtain the mesh cells at the corresponding positions of each layer, and labeling the mesh cell refers to the mesh cell with a label.

[0057] S15, perform independent data segmentation processing on the initial hierarchical model to generate a hierarchical simulation model.

[0058] Understandably, although the model is divided into layers after the overall mesh is cut, the nodes on the intersecting surfaces of the layers are originally shared in terms of data. This means that the model cannot simulate interlayer interaction and peeling defects. Therefore, all common nodes located on the spatial slice surface can be split. For example, the node A, which was originally shared by the bottom of the first layer and the top of the second layer, can be split into node A1 and node A2. Node A1 belongs to the first layer, and node A2 belongs to the second layer. However, these two nodes are completely coincident in the initial spatial coordinates, so that the corresponding nodes can be associated with the interlayer friction loss formula. This allows each layer of mesh to have an independent node label and mesh cell list belonging to the corresponding layer, so that it can independently carry, record, and output the simulation data of this layer in the dynamic simulation, thereby obtaining a layered simulation model.

[0059] In some embodiments, the specific implementation of step S15 (the independent data segmentation processing of the initial hierarchical model to generate a hierarchical simulation model) includes: S151, the common nodes located on each spatial slice surface in the initial layered model are split and labeled to obtain contact pairs.

[0060] It is understandable that existing node splitting technology can be used to split the common nodes located on each spatial slice surface into two parts, and then label the split nodes. This allows the corresponding set of split nodes to be used as contact pairs, so that they can be associated with preset data in the future, making it easier to independently carry, record and output the simulation data of the corresponding layer.

[0061] Among them, the common node is the corresponding node that contacts the spatial slice surface and the two layers of mesh after layering. The contact pair is a set of node pairs after the common node is split, such as node A1 and node A2 as a contact pair.

[0062] S152, retrieve the interlayer friction loss formula and correlate it with the data of each contact pair to obtain the layered simulation model.

[0063] Understandably, the interlayer friction loss formula is retrieved and correlated with the data of each contact pair to obtain a layered simulation model.

[0064] S2, Based on the ply parameters, the layered simulation model is subjected to ply force-thermal coupling simulation processing to obtain simulation data.

[0065] It should be noted that existing technologies only perform static simulations at room temperature and cannot match the high-temperature molding of carbon carbon. Therefore, this invention can use a layered simulation model as a carrier, drive a virtual layup tool to lay up layers according to the layup parameters, first calculate the mechanical response at room temperature, then apply a temperature field to calculate the high-temperature thermodynamic response, and integrate mechanical and thermal effects to obtain complete simulation data.

[0066] It is understandable that the simulation data refers to the data generated during the layer-layout simulation process of the layered simulation model.

[0067] It is not difficult to understand that, as Figure 3 As shown, after obtaining the simulation data, the simulation data can be compared with the preset standard index parameters for preform forming, i.e., the preset standard forming index, so as to correct the ply parameters through simulation, in order to determine the correct ply parameters that meet the requirements for preform ply forming, thereby improving the accuracy and efficiency of preform ply parameters determination.

[0068] It is worth mentioning that when simulating the layered simulation model, the carbon fiber orthotropic constitutive model and the carbon-carbon composite material-specific thermo-mechanical coupling simulation formula system are imported into the layered simulation model so that the entire process of fiber laying, interlayer bonding, compaction deformation and stress transmission can be dynamically simulated, and simulation data including stress data, deformation data and displacement deviation data can be collected in real time during the layup process.

[0069] In some embodiments, the specific implementation of step S2 (the step of performing ply stress-thermal coupling simulation processing on the layered simulation model based on the ply parameters to obtain simulation data) includes: S21, based on the ply parameters, control the virtual plying tool to perform layer-by-layer plying simulation, and obtain the mechanical ply response and initial ply offset of the current ply layer.

[0070] It should be noted that before the formal simulation process, the principal axes of the carbon fiber orthotropic constitutive models corresponding to each layer of mesh elements in the layered simulation model need to be aligned based on the fiber layup angle and single-layer layup thickness in the layup parameters. This will obtain the local coordinate system of each mesh element. In finite element analysis, the constitutive model is used to describe the mathematical relationship of how a material deforms under stress or heat. Ordinary metallic materials have the same properties in all directions, i.e., isotropic. However, carbon fiber fabric is completely different. It is extremely strong along the fiber direction and extremely weak perpendicular to the fiber direction. Therefore, a carbon fiber orthotropic constitutive model can be imported. Specifically, this carbon fiber orthotropic constitutive model defines three mutually perpendicular elastic principal axes in three-dimensional space: the fiber principal direction corresponds to the first axis in the local coordinate system, the in-plane transverse direction corresponds to the first axis in the local coordinate system, and the thickness direction corresponds to the first axis in the local coordinate system. The constitutive model also imports the core material parameter matrices such as the elastic modulus. This allows the simulation software to understand the proportion of deformation in different directions of each mesh layer when subjected to layup mechanical force or high temperature.

[0071] Understandably, once the accurate stage is completed, room temperature dynamic layup and compaction deformation simulation can be performed. That is, by using a virtual layup tool to perform layer-by-layer layup simulation according to the layup parameters, the mechanical response such as fiber tension, tensile deformation, and interlayer shear stress can be calculated, and the initial offset generated during the layup process can be obtained to complete the full simulation of room temperature layup behavior.

[0072] Among them, the virtual laying tool is a tool for laying fiber layers in each grid during the simulation process, such as a virtual compaction roller or laying head. Since it is necessary to lay fiber cloth in the grid, the grid layer currently being laid is determined in real time during the room temperature laying process. The current laying layer is the grid layer currently being laid and compacted. The mechanical layup response is the stress data after applying compaction pressure to the current laying layer. The initial layup offset is the displacement offset caused by the tension stress of fiber laying during the room temperature laying process.

[0073] In some embodiments, the specific implementation of step S21 (the simulation of layer-by-layer laying based on ply parameters using a virtual laying tool to obtain the mechanical ply response and initial ply offset of the current layer) includes: S211, based on the laying travel rate and interlayer compaction pressure, the virtual laying tool is controlled to move along a preset three-dimensional trajectory on the mesh surface of the current laying layer, and the fiber laying tension stress of the mesh nodes is extracted based on the solver.

[0074] Understandably, the virtual tool is controlled to move along a preset three-dimensional trajectory according to the layup rate, and the interlayer compaction pressure of the grid cells is applied to achieve the simulation process of room temperature layup. Then, the fiber layup tension stress of the grid nodes can be extracted by the solver to calculate the mechanical layup response and initial layup offset of the current layup layer.

[0075] Among them, the laying travel rate is an index value in the layup parameters, that is, the moving speed of the simulated precast body laying, which is preset, such as 5mm / s; the interlayer compaction pressure is the preset compaction pressure during the laying process, such as 0.2Mpa; the preset three-dimensional trajectory is the laying movement trajectory, which is preset; and the fiber laying tension stress is the tension generated during fiber laying.

[0076] It is easy to understand that during the simulation, the virtual placement tool moves along the trajectory and applies a mechanical tension vector along the placement tangent direction, i.e., the first axis, to the mesh nodes of the fiber mesh element. The upper limit of the mechanical tension vector is determined by the preset fiber tension threshold of 5-35N. The solver calculates the mechanical strain along the fiber direction based on the node displacement of the current mesh element, calls the carbon fiber orthotropic constitutive model, extracts the elastic modulus along the fiber direction at the current temperature, performs stress recovery through the matrix form of Hooke's law, and directly calculates the fiber placement tension stress at the Gaussian integration point. The elastic modulus is 230GPa at room temperature and 185GPa at high temperature.

[0077] S212, input the fiber layup tension stress and elastic modulus into the fiber tensile deformation formula to obtain the carbon fiber layup tensile deformation strain.

[0078] It is understandable that the formula for fiber tensile deformation is: , The tensile strain of the carbon fiber layup. For fiber layup tension stress, The value represents the elastic modulus of carbon fiber as a function of temperature, taken as 230 GPa at room temperature and 185 GPa under high-temperature carbonization conditions. is the coefficient of thermal expansion of carbon fiber, in °C, and is a constant value of -1.7×10^(-6) °C; This is due to the temperature difference during molding.

[0079] It's easy to understand that since this laying stage is at room temperature, the elastic modulus in the formula is 230 GPa. No heating treatment was performed, resulting in a molding temperature difference. It is 0.

[0080] It is worth mentioning that by substituting the fiber layup tension stress and the elastic modulus at the corresponding temperature into the fiber tensile deformation formula, the tensile deformation strain of the carbon fiber layup during the room temperature layup process can be calculated, which can directly reflect whether the layup is tensile, loose, or wrinkled.

[0081] S213, obtain the actual spatial coordinates and preset trajectory coordinates of the current marked grid cell, perform displacement offset calculation, and obtain the initial ply offset.

[0082] Understandably, the initial ply offset generated during the laying process is calculated by comparing the actual spatial coordinates of the current marked grid cell with the preset theoretical trajectory coordinates.

[0083] The system can locate the currently laid-out marked mesh cell based on the layer domain label, extract all the node labels contained in the cell, read the real-time coordinate values ​​(x, y, z) of these nodes in the current simulation step from the solver's current calculation result database, and integrate these node coordinates to obtain the actual spatial coordinates of the marked mesh cell.

[0084] S214, calculate and update the in-plane transverse shear stress between the updated layup layer and the adjacent layup layer according to the interlayer activation mechanism.

[0085] It is understandable that when the first layer is laid and a new layer of mesh is laid, the relative motion between the upper and lower layers of mesh at the current moment will generate inter-fiber slippage. The current inter-fiber friction force can be calculated by the solver and converted into in-plane transverse shear stress. If the in-plane transverse shear stress cannot balance the tension of the virtual laying tool, the mesh will spontaneously generate excess shear strain. It is necessary to determine whether slippage, peeling, or wrinkling will occur, so as to determine whether the layup parameters configured can simulate a prefabricated body that meets the standard.

[0086] Among them, the in-plane transverse shear stress is the shear force per unit area generated between adjacent layup layers in a direction parallel to the layup plane.

[0087] In some embodiments, a specific implementation of step S214 (calculating the in-plane transverse shear stress between the updated layup layer and the adjacent layup layer according to the interlayer activation mechanism) includes: S2141, determine that a new layer of mesh is laid to obtain an updated layer, activate the contact pairs corresponding to the adjacent layers based on the updated layer, and obtain the interlayer compaction pressure of the current updated layer and the interlayer slip of the fibers corresponding to the adjacent layers.

[0088] Understandably, once a new layer of mesh is laid, it is designated as the updated layer. The system automatically activates the pre-established contact pair between the updated layer and the adjacent layer below it. At the same time, it reads the interlayer compaction pressure applied by the current updated layer from the simulation system and extracts the amount of inter-fiber slippage generated between adjacent layers so as to calculate the inter-fiber friction force in the future.

[0089] Among them, the updated layer is the mesh layer being laid out for simulation processing at the current moment, and the slip between fiber layers is the difference in the relative displacement vector between two nodes in the tangential direction of the contact surface.

[0090] It is easy to understand that the amount of inter-fiber slip originates from the relative spatial displacement difference between two adjacent unit nodes in the contact pair. That is, when the virtual tool moves or the material is deformed by heat, nodes A1 and A2 generate spatial position vectors. The contact slip tracking algorithm calculates the relative displacement vector difference between these two nodes in the tangential direction of the contact surface in each time step, thereby obtaining the amount of inter-fiber slip.

[0091] S2142, input the interlayer compaction pressure, fiber interlayer slippage, friction coefficient and roughness correction coefficient into the interlayer friction loss formula to calculate the fiber interlayer friction force.

[0092] It is understandable that the formula for interlayer friction loss is: ,in, The interlayer friction force (N) is the force between the fiber layers. The value is 0.32 for the dynamic friction coefficient between carbon cloth layers, taken as 0.21 at room temperature and 0.32 under pre-carbonization conditions. Where is the interlayer compaction pressure (N), and K is the fiber surface roughness correction factor, with a value of 0.08. The amount of interlayer slippage (mm) is used to simulate frictional loss and slippage defects during the carbon cloth lamination process.

[0093] S2143, based on the ratio of the interlayer friction force of the fiber to the area of ​​the mesh unit, the in-plane transverse shear stress is obtained.

[0094] It is understandable that by converting the ratio of interlayer friction to mesh element area, the concentrated friction is transformed into in-plane transverse shear stress acting per unit area, making the interlayer mechanical behavior recognizable and calculated by the finite element simulation system.

[0095] S215, the mechanical response of the carbon fiber layup is obtained based on the tensile strain and in-plane transverse shear stress of the carbon fiber layup.

[0096] It is understandable that the mechanical response of mechanical layup is the total output of mechanical layup behavior at room temperature, integrating tension and shear, including the tensile strain and in-plane transverse shear stress of carbon fiber layup, thus comprehensively reflecting the self-deformation and interlayer interaction state of the fiber during the layup and compaction process.

[0097] S22 simulates the heating of the precast body of the target component based on time-varying temperature load, and obtains the thermodynamic coupling response and fiber placement offset compensation amount at each temperature in real time.

[0098] It should be noted that carbon-carbon thermal field components need to undergo high temperatures above 1000℃. The fiber elastic modulus, interlaminar friction coefficient, thermal shrinkage, and thermal stress all change with temperature. Room temperature simulation cannot reflect the actual high-temperature deformation and defects, so temperature-coupled calculation is required. Therefore, after the room temperature layup simulation is completed, a time-varying temperature load is applied to the preform, and the temperature is gradually increased to simulate the high-temperature process. The thermodynamic behavior at different temperatures is calculated in real time and the thermodynamic coupling response is output. At the same time, the fiber layup offset compensation amount is obtained according to the high-temperature displacement compensation algorithm to correct the layup path deviation and realize the full-process coupled simulation of room temperature layup and high-temperature molding.

[0099] Understandably, by applying a high-temperature environment to the simulated preform using a preset time-temperature curve, the simulation process of the ambient temperature gradually increasing over time is simulated. In the high-temperature carbonization simulation, the thermodynamic coupling response and fiber placement offset compensation amount are recorded in real time at each temperature. This facilitates the determination of whether defects occur in the preform and the parameters when defects occur, so that the process parameters can be corrected through iterative simulation, thereby improving the accuracy and efficiency of the preform simulation.

[0100] Among them, the prefabricated body is the simulation model corresponding to the target component, the time-varying temperature load is the temperature load that changes with time, which can be simulated by a pre-set temperature change curve, the thermodynamic coupling response is the index value of stress between different layers under high temperature environment, and the fiber placement offset compensation amount is the compensation value for the fiber placement layer offset under high temperature environment.

[0101] In some embodiments, the specific implementation of step S22 (the real-time acquisition of the thermodynamic coupling response and fiber placement offset compensation at each temperature node) includes: S221, after determining the layup simulation, the preform of the target component is heated based on the time-varying temperature load, and the forming temperature difference is obtained based on the temperature difference between the current temperature and the initial temperature.

[0102] Understandably, when the number of fiber layers reaches the preset number of layers, after the layup simulation is completed, a time-varying temperature load is applied according to the actual high-temperature process curve of carbon-carbon materials, and the preform is gradually heated from room temperature to the target high temperature. During the heating process, the current temperature is subtracted from the initial room temperature in real time to obtain the molding temperature difference corresponding to different times.

[0103] Among them, the current temperature is the temperature corresponding to the current moment, the initial temperature is a preset value, such as 25 degrees, and the molding temperature difference is the temperature difference between the current moment and the initial moment during the high-temperature molding process.

[0104] S222, Based on the current temperature, the friction coefficient and elastic modulus are numerically switched to obtain the current friction coefficient and current elastic modulus.

[0105] It is understandable that the dynamic friction coefficient between carbon cloth layers and the elastic modulus of carbon fiber with temperature change are different under normal temperature and high temperature carbonization working conditions. Therefore, when the current temperature is determined to be the temperature under high temperature carbonization working conditions, the friction coefficient and elastic modulus are numerically switched in order to calculate the accurate thermodynamic coupling response under high temperature carbonization.

[0106] The current friction coefficient is the friction coefficient after switching at high temperature, and the current elastic modulus is the elastic modulus corresponding to the current temperature. Both are preset. If the current temperature is normal temperature, the friction coefficient and elastic modulus will not be changed.

[0107] S223, calculate the thermal friction force based on the current friction coefficient to obtain the interlayer friction force of the thermal fibers, and obtain the transverse shear stress in the thermal surface based on the ratio of the interlayer friction force of the thermal fibers to the area of ​​the mesh unit.

[0108] It is understandable that by substituting the current friction coefficient into the interlayer friction loss formula, the interlayer friction force of the thermal fiber at the current moment in the high-temperature carbonization simulation can be obtained. The ratio of the interlayer friction force of the thermal fiber to the area of ​​the mesh element can be calculated to obtain the transverse shear stress in the hot surface.

[0109] Wherein, the interlayer friction force of the thermal fibers is the interlayer friction force of the thermal fibers at the current moment during the high-temperature carbonization simulation, the in-plane transverse shear stress is the in-plane transverse shear stress at the current moment during the high-temperature carbonization simulation, and the formula for interlayer friction loss is: .

[0110] S224, obtain the transient thermal stress, input the transient thermal stress and the current elastic modulus into the fiber tensile deformation formula to obtain the thermal deformation strain of the carbon fiber layup.

[0111] It is understandable that heat is conducted layer by layer from the outside to the inside of the target component. Each layer of the mesh will experience different thermal expansion or contraction due to the temperature difference during molding. Because the fiber orientation of each layer is different, such as 0 degrees, 90 degrees, and 45 degrees, adjacent layers will restrain each other and cannot expand freely. As a result, huge thermal stress, i.e., transient thermal stress, will be generated inside the mesh. This thermal stress, in turn, will cause the preform to undergo severe deformation such as overall warping and local interlayer delamination. Therefore, by obtaining the transient thermal stress, the thermal deformation strain of the carbon fiber layup can be calculated to determine whether the preform has defects under the current process parameters.

[0112] Wherein, transient thermal stress is the instantaneous thermal stress within the fiber layer, and the fiber tensile deformation formula is: At this time For transient thermal stress, thus obtained The value represents the thermal deformation strain of the carbon fiber layup; the rest is consistent with the values ​​for the layup at room temperature described above.

[0113] It is easy to understand that after introducing time-varying temperature loads and calculating the molding temperature difference, the functional thermal strain vectors that should be generated in each direction of the mesh under free state can be calculated based on the constant thermal expansion coefficient. Since the mesh is layered and stacked and the fibers are laid out in an interlaced manner, they cannot expand freely. Therefore, the stress confined between layers will be transformed into internal stress within the mesh. The solver can solve the full stiffness matrix equation in the orthotropic constitutive model of carbon fiber and calculate the transient thermal stress tensor at the Gaussian integration point. The transient thermal stress tensor is a six-dimensional matrix based on the global coordinate system of XYZ axes, containing the normal stresses in the three directions of X, Y, and Z axes and the shear stresses in the three directions of XY, YZ, and XZ axes. Therefore, in order to extract the specific directional force that has the greatest impact on carbon fiber, the simulation system can call the local coordinate system to perform a coordinate projection transformation algorithm, multiply the six-dimensional tensor matrix by the local direction cosine matrix, and thus obtain the component projected onto the 1-axis of the local coordinate system, which is the transient thermal stress along the fiber direction.

[0114] S225, the thermodynamic coupling response is obtained based on the transverse shear stress in the hot surface and the thermal deformation strain of the carbon fiber layup.

[0115] It is understandable that the thermodynamic coupling response includes in-plane transverse shear stress and thermal deformation strain of the carbon fiber layup.

[0116] S226. Input the initial offset, thermal shrinkage coefficient, laying error correction coefficient, and molding temperature difference into the high-temperature displacement compensation formula to obtain the fiber laying offset compensation amount.

[0117] Understandably, since the preform will shrink and deform under high temperature carbonization working conditions, the initial offset, thermal shrinkage coefficient, laying error correction coefficient and molding temperature difference can be input into the high temperature displacement compensation formula to obtain the fiber laying offset compensation amount, so as to correct the fiber offset and high temperature shrinkage deformation in the hot field irregular curved surface laying process in real time.

[0118] The high-temperature displacement compensation formula is as follows: , The fiber placement offset compensation amount (mm). This represents the initial layup offset (mm). The coefficient of thermal shrinkage for carbon fiber is 0.0015. The equipment placement error correction factor is set to a constant value of 0.02. This is due to the temperature difference during molding.

[0119] S23, the simulation data is obtained based on the mechanical layup response, thermodynamic coupling response, and fiber layup offset compensation.

[0120] It is understandable that only by integrating room temperature mechanical behavior, high temperature thermodynamic behavior, and displacement compensation can complete simulation data that can be used for defect identification be formed. That is, the simulation data includes the mechanical layup response, thermodynamic coupling response, and fiber layup offset compensation during the entire simulation process.

[0121] S3. Based on the simulation data, perform defect identification to obtain defect identification results. Based on the defect identification results, iteratively correct the layup parameters to obtain corrected parameters.

[0122] It should be noted that the simulation data obtained during the simulation process is compared with the index parameters of the standard target component precast molding. Thus, it is possible to determine whether the current precast is qualified based on the simulation data, and the degree of defect corresponding to non-compliance. The process parameters of the simulation can be corrected based on the degree of defect to obtain corrected parameters. The simulation is then repeated based on the corrected parameters until the defect identification result shows that the precast simulation data meets all the indexes of standard precast molding, at which point the simulation stops.

[0123] Among them, the defect identification result is the result of comparing the numerical values ​​of the simulation data, and the correction parameter is the parameter after correcting the ply parameters.

[0124] It is easy to understand that during the simulation process, the model will compare the simulation data with the preset standard model in real time. When the data exceeds the threshold range, it will be automatically marked as a defect, and the defect level will be determined according to the size of the deviation. The larger the deviation, the more serious the level.

[0125] In some embodiments, the specific implementation of step S3 (identifying defects based on the simulation data, obtaining defect identification results, and iteratively correcting the layup parameters based on the defect identification results to obtain corrected parameters) includes: S31, the simulation data is compared one by one based on the preset standard molding index to obtain the defect identification results, which include minor defect results, general defect results and serious defect results.

[0126] Understandably, the preset standard forming index is the standard index for the qualified forming of the preform. It is set in advance by humans. The result of a minor defect is that the simulation data deviates slightly or without deviation from the preset standard forming index, that is, there is a deviation of the corresponding index value within the judgment range of minor defects. The result of a general defect is that the simulation data deviates more significantly from the preset standard forming index, that is, there is a deviation of the corresponding index value within the judgment range of general defects. The result of a serious defect is that the simulation data deviates significantly from the preset standard forming index, that is, there is a deviation of the corresponding index value within the judgment range of serious defects.

[0127] It is easy to understand that all indicators are within the threshold and have no defects. If an individual indicator is slightly out of range but does not affect performance, it is judged as a minor defect. If an indicator is out of range but can be corrected to a small extent, it is judged as a general defect. If an indicator is out of range and cannot be used, it is judged as a serious defect.

[0128] It is worth mentioning that, based on the carbon-carbon thermal field preform molding standard, the threshold values ​​corresponding to the preset standard molding indicators can be: carbon fiber layup tensile or thermal deformation strain ≤0.008, fiber interlayer slip ≤0.1mm, fiber layup offset compensation ≤0.15mm, and fiber thickness deviation ≤±0.03mm. The defect identification result is determined by calculating the deviation rate between the simulated real-time measured values ​​and the threshold values, i.e., deviation rate = (simulated value - threshold) / threshold × 100%. When the deviation rate is less than 20%, it is determined as a minor defect; when the deviation rate is between 20% and 50%, it is determined as a general defect; and when the deviation rate is greater than 50%, it is determined as a serious defect. That is, during the simulation process, abnormal defects in the simulation process will be structurally marked in real time. Each mesh cell is categorized by layer domain label and 3D coordinates. Cells exceeding a threshold are marked with defect labels. These labels include defect type, quantization deviation value, and defect level, and are visualized. Defect types include wrinkles, interlayer delamination, fiber misalignment, and thickness unevenness. Quantization deviation values ​​include mechanical layup response, thermodynamic coupling response, and the offset corresponding to fiber layup offset compensation. Defect levels are categorized as minor, moderate, and severe. Visualization involves processing the mesh cells according to their defect levels: minor defects are marked with yellow dots, moderate defects with orange triangles, and severe defects with red squares. By marking mesh cells during simulation, subsequent adjustments to process and layup parameters can be made to obtain corrected parameters.

[0129] S32, when the defect identification result is determined to be a general defect result, the laying travel rate and interlayer compaction pressure are finely adjusted to obtain the corrected laying travel rate and corrected interlayer compaction pressure.

[0130] Understandably, common defects such as slight misalignment, small wrinkles, and localized looseness are usually caused by unstable laying speed and insufficient compaction. Therefore, they can be repaired by simply adjusting local parameters without changing the overall scheme. The built-in strategy can automatically adjust the laying speed and interlayer compaction pressure by slightly increasing or decreasing the laying speed within the range of 5–25 mm / s and slightly increasing or decreasing the interlayer compaction pressure within the range of 0.2–1.5 MPa.

[0131] Among them, the corrected laying travel rate is the laying speed after fine-tuning for general defects, and the corrected interlayer compaction pressure is the compaction pressure after fine-tuning for general defects.

[0132] S33, when the defect identification result is determined to be a serious defect result, the laying angle and fiber tension are iterated again to obtain the corrected laying angle and corrected fiber tension.

[0133] Understandably, severe defects such as large-area wrinkles, interlayer delamination, severe misalignment, and severe thickness unevenness originate from incorrect layup direction and unreasonable tension. These are core parameter errors that cannot be fine-tuned by layup travel rate and interlayer compaction pressure. Therefore, a global re-iteration simulation is required to perform simulation corrections from the fiber layup stage, thereby improving the accuracy and efficiency of determining the correct layup parameters.

[0134] Among them, the corrected layup angle is the layup direction after iterative correction of severe defects, and the corrected fiber tension is the fiber tension force after iterative correction of severe defects.

[0135] S34, the correction parameters are obtained by correcting the laying travel rate, correcting the interlayer compaction pressure, correcting the laying angle and correcting the fiber tension.

[0136] Understandably, the corrected layup rate, corrected compaction pressure, corrected layup angle, and corrected fiber tension are integrated by type to form complete corrected layup parameters for use in the next round of simulation.

[0137] S4, when the simulation data corresponding to the correction parameters meets the standard production indicators, output the layup scheme.

[0138] Understandably, the ultimate goal of iteration is to obtain a standard process solution that can be directly used in automated production, ensuring first-time molding qualification without the need for physical trial production, thereby improving production efficiency. Therefore, as... Figure 3 As shown, if all the output simulation data meets the standard production indicators, the iteration stops and the final layup scheme is output.

[0139] Among them, the layup scheme is a standardized production scheme that integrates optimal layup process parameters, visualized layup path drawings, mesh generation parameters, molding defect avoidance schemes and mechanical property simulation data reports, and can be directly connected to automated layup equipment.

[0140] See Figure 4 This is a schematic diagram of the hardware structure of an electronic device provided in an embodiment of the present invention. The electronic device 40 includes: a processor 41, a memory 42, and a computer program; wherein... The memory 42 is used to store the computer program, and the memory may also be flash memory. The computer program is, for example, an application program or functional module that implements the above method.

[0141] The processor 41 is configured to execute the computer program stored in the memory to implement the various steps performed by the device in the above method. For details, please refer to the relevant descriptions in the preceding method embodiments.

[0142] Alternatively, the memory 42 can be either standalone or integrated with the processor 41.

[0143] When the memory 42 is a device independent of the processor 41, the device may further include: Bus 43 is used to connect the memory 42 and the processor 41.

[0144] The present invention also provides a readable storage medium storing a computer program, which, when executed by a processor, is used to implement the methods provided in the various embodiments described above.

[0145] The readable storage medium can be a computer storage medium or a communication medium. A communication medium includes any medium that facilitates the transfer of computer programs from one location to another. A computer storage medium can be any available medium accessible to a general-purpose or special-purpose computer. For example, a readable storage medium is coupled to a processor, enabling the processor to read information from and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can reside in an Application-Specific Integrated Circuit (ASIC). Alternatively, the ASIC can be located in a user equipment. Of course, the processor and the readable storage medium can also exist as discrete components in a communication device. The readable storage medium can be a read-only memory (ROM), random access memory (RAM), CD-ROM, magnetic tape, floppy disk, and optical data storage device, etc.

[0146] The present invention also provides a program product including executable instructions stored in a readable storage medium. At least one processor of the device can read the executable instructions from the readable storage medium, and the at least one processor executes the executable instructions to cause the device to implement the methods provided in the various embodiments described above.

[0147] In the embodiments of the above-described device, it should be understood that the processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this invention can be directly manifested as execution by a hardware processor, or execution by a combination of hardware and software modules within the processor.

[0148] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A 3D simulation method for prefabricated body layup, characterized in that, include: Based on the modeling data of the target component, a standard three-dimensional model of the target component is constructed, the plying parameters of the target component are configured, and the standard three-dimensional model is subjected to adaptive surface mesh layering to obtain a layered simulation model. Based on the ply parameters, the layered simulation model is subjected to ply force-thermal coupling simulation processing to obtain simulation data; Defects are identified based on the simulation data to obtain defect identification results. The layup parameters are then iteratively corrected based on the defect identification results to obtain corrected parameters. When the simulation data corresponding to the corrected parameters meets the standard production indicators, the layup scheme is output.

2. The method according to claim 1, characterized in that, The adaptive surface mesh layering of the standard 3D model to obtain a layered simulation model includes: The standard 3D model is meshed using an adaptive meshing algorithm to obtain a 2D meshed 3D model. The 2D mesh 3D model is filled with a volume mesh to obtain a 3D mesh 3D model; Based on the shape characteristics and ply parameters of the target component, multiple spatial slice surfaces are generated along the normal direction of the target component; The 3D mesh model is cut based on the spatial slicing surface and geometric intersection algorithm to obtain an initial layered model. The initial hierarchical model is processed by independent data segmentation to generate a hierarchical simulation model.

3. The method according to claim 2, characterized in that, The step of meshing the standard 3D model using an adaptive meshing algorithm to obtain a 2D meshed 3D model includes: Identify the boundary surfaces of a standard 3D model and extract geometric patches, then calculate the principal curvature of each geometric patch based on a differential geometry algorithm; The comparison is performed between the principal curvature and the preset curvature threshold to obtain the comparison result, and the mesh node density of the corresponding geometric patch is determined based on the comparison result. Based on the stated grid node density, a topological mesh is generated on the boundary surface to obtain a 2D mesh 3D model.

4. The method according to claim 3, characterized in that, The 3D mesh model is cut based on the spatial slicing surface and geometric intersection algorithm to obtain an initial layered model, including: Based on the geometric intersection algorithm, the spatial slice surface is passed through the mesh cells of the 3D mesh model to obtain intersecting cells; The intersecting cells are reconstructed into mesh cells to generate multiple reconstructed mesh cells. The reconstructed mesh cells are then labeled with layer domain labels to obtain an initial hierarchical model with labeled mesh cells.

5. The method according to claim 4, characterized in that, The step of performing independent data segmentation processing on the initial hierarchical model to generate a hierarchical simulation model includes: The common nodes located on each spatial slice surface in the initial layered model are split and labeled to obtain contact pairs; The interlayer friction loss formula is retrieved and correlated with the data of each contact pair to obtain a layered simulation model.

6. The method according to claim 5, characterized in that, The layered simulation model is subjected to ply force-thermal coupling simulation processing based on the ply parameters to obtain simulation data, including: A layer-by-layer laying simulation is performed using a virtual laying tool controlled by layup parameters to obtain the mechanical layup response and initial layup offset of the current layer. The precast body of the target component is subjected to heating simulation based on time-varying temperature load, and the thermodynamic coupling response and fiber placement offset compensation amount are obtained in real time at each temperature. The simulation data are obtained based on the mechanical layup response, thermodynamic coupling response, and fiber layup offset compensation.

7. The method according to claim 6, characterized in that, The virtual laying tool based on ply parameters performs layer-by-layer laying simulation to obtain the mechanical ply response and initial ply offset of the current layer, including: The virtual laying tool is controlled to move along a preset three-dimensional trajectory on the mesh surface of the current laying layer based on the laying travel rate and interlayer compaction pressure, and the fiber laying tension stress of the mesh nodes is extracted based on the solver. By inputting the fiber layup tension stress and elastic modulus into the fiber tensile deformation formula, the tensile deformation strain of the carbon fiber layup is obtained. Obtain the actual spatial coordinates and preset trajectory coordinates of the current marked grid cell, perform displacement offset calculations, and obtain the initial ply offset. The in-plane transverse shear stress between the updated layup layer and the adjacent layup layer is calculated based on the interlayer activation mechanism. The mechanical response of the carbon fiber layup was obtained based on the tensile strain and in-plane transverse shear stress of the carbon fiber layup.

8. The method according to claim 7, characterized in that, The calculation of the in-plane transverse shear stress between the updated layup layer and adjacent layup layers based on the interlayer activation mechanism includes... A new layer of mesh is laid to obtain an updated layer. Based on the updated layer, the contact pairs corresponding to the adjacent layers are activated, and the interlayer compaction pressure of the current updated layer and the interlayer slippage of the fibers corresponding to the adjacent layers are obtained. The interlayer friction force is calculated by inputting the interlayer compaction pressure, fiber interlayer slip, friction coefficient and roughness correction coefficient into the interlayer friction loss formula. The in-plane transverse shear stress is obtained based on the ratio of the interlayer friction of the fibers to the area of ​​the mesh unit.

9. The method according to claim 8, characterized in that, The real-time acquisition of the thermodynamic coupling response and fiber placement offset compensation at each temperature node includes: After determining the layup simulation, the preform of the target component is heated based on the time-varying temperature load, and the forming temperature difference is obtained based on the temperature difference between the current temperature and the initial temperature. The friction coefficient and elastic modulus are switched numerically based on the current temperature to obtain the current friction coefficient and current elastic modulus; The thermal friction force is calculated based on the current friction coefficient to obtain the interlayer friction force of the thermal fibers. Based on the ratio of the interlayer friction force of the thermal fibers to the area of ​​the mesh unit, the transverse shear stress in the thermal surface is obtained. The transient thermal stress is obtained, and the transient thermal stress and the current elastic modulus are input into the fiber tensile deformation formula to obtain the thermal deformation strain of the carbon fiber layup. The thermodynamic coupling response is obtained based on the transverse shear stress in the hot surface and the thermal deformation strain of the carbon fiber layup. The initial offset, thermal shrinkage coefficient, laying error correction coefficient, and molding temperature difference are input into the high-temperature displacement compensation formula to obtain the fiber laying offset compensation amount.

10. The method according to claim 9, characterized in that, The step involves identifying defects based on the simulation data to obtain defect identification results, and then iteratively correcting the layup parameters based on the defect identification results to obtain corrected parameters, including: The simulation data is compared one by one based on the preset standard molding index to obtain the defect identification results, which include no defect results, minor defect results, general defect results and serious defect results. When the defect identification result is determined to be a general defect result, the laying travel rate and interlayer compaction pressure are finely adjusted to obtain the corrected laying travel rate and corrected interlayer compaction pressure. When the defect identification result is determined to be a severe defect, the layup angle and fiber tension are iterated again to obtain the corrected layup angle and corrected fiber tension; The correction parameters are obtained by correcting the laying travel rate, interlayer compaction pressure, laying angle, and fiber tension.

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