Curing deformation simulation method and equipment for composite material structural member, medium and product

Abstract

The invention discloses a composite material structural member curing deformation simulation method and device, a medium and a product, and relates to the field of composite material manufacturing. The method comprises the following steps: firstly, acquiring paving layer information of all paving layers in the composite material structural member and a boundary line of each paving layer; a mold model of the composite material structural part is obtained and subjected to geometric treatment, and a two-dimensional model of the mold attaching face of the mold is constructed; the boundary lines of all the laying layers are projected to a mold attaching face, the mold attaching face is divided according to the projected boundary lines of all the laying layers, the mold attaching face is divided into a plurality of areas, and 2D grids are divided on the mold attaching face in a sub-area mode; sequentially stretching the 2D grids layer by layer in combination with the paving layer information of all paving layers to generate a three-dimensional finite element model of the composite material structural member; and performing curing deformation simulation based on the three-dimensional finite element model of the composite material structural member, and predicting deformation and defects in the curing forming process. According to the method, the modeling efficiency and precision of the large complex grid model can be improved, and the curing deformation simulation process is accelerated.

Description

Technical Field

[0001] The present application relates to the technical field of composite material manufacturing, and in particular to a method, equipment, medium and product for simulating the curing deformation of composite material structural parts. Background Art

[0002] Composite materials are widely used in fields such as aerospace due to their high specific strength, high specific modulus, excellent heat resistance, and excellent fatigue resistance. Currently, the aerospace industry primarily uses autoclaves to cure and mold resin-based composite structural components. During the autoclave curing process, temperature gradients and residual stresses inevitably develop within the composite components due to changes in the temperature distribution within the autoclave and the exothermic effect of the resin curing reaction, leading to deformation and natural defects. Finite element simulation technology can accurately and quickly predict composite curing deformation.

[0003] In the past, when finite element simulation was used to analyze composite structural components, the mesh model of the structural component relied on the original geometric model. This mesh model was generated by first importing the structural component's geometric model and then manually discretizing it into a mesh. Obviously, for large composite structural components with complex internal layup structures, manually dividing the geometric model into layers of meshes is inefficient or even impossible, resulting in a low efficiency in the solidification deformation simulation process. Summary of the Invention

[0004] The purpose of this application is to provide a method, equipment, medium and product for simulating the curing deformation of composite structural parts to improve the modeling efficiency and accuracy of large and complex grid models and accelerate the curing deformation simulation process.

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

[0006] In a first aspect, the present application provides a method for simulating the curing deformation of a composite material structural component, comprising:

[0007] Obtain the layup information of all layers inside the composite structure and the boundary lines of each layer; the layup information of all layers includes the material parameters, layer thickness, layer angle and covering area of ​​each layer;

[0008] Obtain the mold model of the composite structural part and perform geometric processing to construct a two-dimensional model of the mold surface;

[0009] Projecting the boundary lines of each ply onto the mold mounting surface, and segmenting the mold mounting surface according to the projected boundary lines of each ply, dividing the mold mounting surface into several regions, and dividing the 2D grid on the mold mounting surface according to the regions;

[0010] Combining the layup information of all layers, the 2D mesh is stretched layer by layer to generate a 3D finite element model of the composite structure;

[0011] Perform curing deformation simulation based on the 3D finite element model of composite structural parts to predict deformation and defects during the curing molding process.

[0012] Optionally, the material parameters of each ply include thermal performance parameters of the composite material, mechanical parameters of the composite material and curing kinetic parameters of the composite material; the thermal performance parameters of the composite material include mass density, specific heat and thermal conductivity; the mechanical parameters of the composite material include Young's modulus, Poisson's ratio and thermal expansion coefficient; the curing kinetic parameters of the composite material include reaction order, activation energy and reaction frequency.

[0013] Optionally, the step of obtaining a mold model of a composite material structural component and performing geometric processing to construct a two-dimensional model of the mold mounting surface specifically includes:

[0014] The mold model of the composite structural part is geometrically processed, only the upper surface of the mold model is retained and unnecessary lines on the surface are cleared to obtain a two-dimensional model of the mold mounting surface.

[0015] Optionally, projecting the boundary lines of each ply onto the mold mounting surface, segmenting the mold mounting surface according to the projected boundary lines of each ply, dividing the mold mounting surface into a plurality of regions, and dividing the 2D grid on the mold mounting surface by region specifically includes:

[0016] The boundary lines of each ply are projected onto the mold mounting surface along the normal direction of the mold mounting surface, and the projected boundary lines of each ply are constructed into closed curves. The mold mounting surface is divided one by one according to each curve, and the mold mounting surface is divided into several areas. 2D grids of preset sizes are divided on the mold mounting surface according to the areas.

[0017] Optionally, after dividing the mold attachment surface into 2D grids of preset sizes, the method further comprises:

[0018] Use different colors to distinguish different areas of the 2D grid.

[0019] Optionally, combining the layup information of all the plies and sequentially stretching the 2D mesh layer by layer to generate a three-dimensional finite element model of the composite material structural component specifically includes:

[0020] Select the paving area of ​​each ply from bottom to top, and stretch the 2D mesh of the corresponding paving area according to the ply thickness and ply angle of each ply until the ply thickness and ply angle of each ply are consistent with the actual ply thickness and angle;

[0021] A grid set is created for the stretched grid corresponding to each ply, and corresponding material parameters are assigned to each grid set to obtain a three-dimensional finite element model of the composite structural component.

[0022] Optionally, when selecting the covering area of ​​each ply, if the selected ply is a dropped ply or a sandwiched ply, an additional circle of triangular meshes is generated on the outer circle of the stretched mesh corresponding to the ply.

[0023] In a second 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 composite material structural component curing deformation simulation method.

[0024] In a third aspect, the present application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the composite material structural component curing deformation simulation method.

[0025] In a fourth aspect, the present application provides a computer program product, comprising a computer program, which, when executed by a processor, implements the composite material structural component curing deformation simulation method.

[0026] According to the specific embodiments provided in this application, this application discloses the following technical effects.

[0027] The present application provides a method, device, medium and product for simulating the curing deformation of composite structural parts. Unlike the previous method of first importing the geometric model of the composite structural part and then manually meshing the geometric model, the method completely combines the overall layup information of the composite structural part and stretches from the bottom of the structural part upward to generate a mesh model that is highly consistent with the layup design of the actual structural part. The method is particularly suitable for the rapid generation of three-dimensional finite element models of complex and large composite structural parts in composite curing deformation simulation, improves the modeling efficiency and accuracy of large complex mesh models, accelerates the curing deformation simulation process, and is of great significance to the engineering application of composite curing deformation simulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. 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 creative work.

[0029] Figure 1 This is a flow chart of a composite material structural component curing deformation simulation method according to the present application;

[0030] Figure 2 Schematic diagram of the mold model and layer loss boundary line in the embodiment of this application;

[0031] Figure 3 Schematic diagram of a 2D grid divided on the film-mounting surface of the mold in an embodiment of the present application;

[0032] Figure 4 This is a cross-sectional view of a three-dimensional finite element model of a composite material structural component in an embodiment of the present application. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0034] Composite material structural parts are all multi-layer structures. In the autoclave molding process, the composite material blank is made of single-layer prepregs stacked in a predetermined direction. In order to meet the requirements of external shape and weight reduction, a large number of layer drops and sandwich structures are required inside large and complex laminated composite material structural parts. For the above-mentioned structure, when using finite element technology to simulate the curing deformation of composite materials, how to quickly and accurately establish a composite material structure grid model with a high degree of consistency with the actual laminate design is a major difficulty in the curing deformation simulation. Therefore, providing a high-precision and high-efficiency composite material modeling method to accelerate the curing deformation simulation process is a key technology in this field. To this end, the present application proposes a composite material structural part curing deformation simulation method, equipment, medium and product, which can achieve high-precision and high-efficiency establishment of a large-scale and complex laminated composite material structural part grid model, effectively improve the modeling efficiency, and accelerate the curing deformation simulation process.

[0035] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0036] In an exemplary embodiment, Figure 1 As shown, a method for simulating curing deformation of a composite material structural component is provided, including the following steps 1 to 5.

[0037] Step 1: Obtain the ply information of all plies inside the composite structure and the boundary lines of each ply.

[0038] On the one hand, according to the layup design scheme of the composite material structural part (hereinafter referred to as the structural part), the layup information of all the plies inside the composite material structural part is obtained, which is called the global layup information of the composite material structural part. The global layup information includes the material parameters, ply thickness, ply angle and draping area of ​​each ply, as well as whether the current ply is a missing layer or a sandwich. Specifically, the material parameters of each ply include composite material thermal performance parameters, composite material mechanical parameters and composite material curing kinetic parameters. Among them, the composite material thermal performance parameters include parameters such as mass density, specific heat and thermal conductivity. The composite material mechanical parameters include parameters such as Young's modulus, Poisson's ratio and thermal expansion coefficient. The composite material curing kinetic parameters include parameters such as reaction order, activation energy and reaction frequency. The layup angle refers to the direction of the fiber in the layup design. The draping area refers to the specific area where the composite material prepreg is laid on the mold. For the convenience of description, the various plies of the composite material structural part may also be referred to as "layers" in the following.

[0039] Furthermore, define the material properties of each layer of the composite structural component. Based on the materials contained within the structural component, set the material name of the single layer, enter the various material parameters required for the curing deformation simulation, and add the defined material parameter properties to the material library for subsequent use when assigning material properties to each layer of mesh.

[0040] On the other hand, the boundary lines of each ply of the composite structural component are organized from bottom to top for use in the subsequent projection process. Specifically, the mold model of the composite structural component is obtained and divided into a two-dimensional grid, where each two-dimensional grid is also called a unit. The mold model of the composite structural component refers to the three-dimensional (3D) geometric model of the structural component mold, which has been established during the mold design. This existing data model can be directly obtained here. In the divided two-dimensional grid, an edge may be shared by multiple units. The edges of all units are traversed and the number of times each edge appears in all units is counted using a hash table. In the statistical table that records the number of times each edge appears in a unit, the edges with an appearance count of 1 are determined to be the edges of the boundary unit, and these edges are added to the list of grid boundaries. This is because in the entire unit set, for an edge that appears only once, it means that the edge belongs to only one unit and no adjacent units share it. Therefore, it can be determined that the edge is an edge of the boundary unit. By connecting the edges of all boundary units of the same ply, the boundary line of the ply can be obtained.

[0041] Step 2: Obtain the mold model of the composite structural part and perform geometric processing to construct a two-dimensional model of the mold surface.

[0042] The mold model of a composite structural component conveys the geometric shape of the composite structural component. Based on the mold model, a mesh model of the composite structural component is constructed using the method described in this application. This is determined by the composite autoclave molding process. A geometric model cannot be used for simulation calculations; only a mesh model can. Therefore, the constructed mesh model is also called a three-dimensional finite element model and can be directly used in finite element simulations.

[0043] Import the mold model of a composite structural component and perform geometric processing. Remove all other parts of the mold model, retaining only the top surface—the mold face. The mold face is the surface in direct contact with the composite prepreg. Use the Merge Faces function to remove unnecessary lines on the face, resulting in a 2D model of the mold face. These unnecessary lines are small features that may have existed on the original mold model, such as the boundaries of small holes. The Merge Faces function can be developed as a plugin using software such as Python.

[0044] A specific implementation algorithm for the merging face function is given below.

[0045] The two-dimensional model of the mold surface is represented as a vertex set V = {v1, v2, ..., v n} and edge set E = {e1, e2, ..., e m}, where each vertex v i Use the two-dimensional coordinates (x i ,y i ) means that each edge e j It is represented by two vertex indices (i, j). A threshold ∈ is defined to determine whether a line segment is small enough to be merged. The output of the algorithm is a cleaned 2D model of the mold surface, containing the updated vertex set V′ and edge set E′.

[0046] The specific algorithm steps of the merge face function include the following steps 2.1 to 2.5.

[0047] Step 2.1: Initialization; Initialize an empty set V′ to store the cleaned vertices, and initialize an empty set E′ to store the cleaned edges.

[0048] Step 2.2: Calculate the length of the edge; for each edge e j =(i, j), calculate its length L(e j ):

[0049]

[0050] Where (x i ,y i ) and (x j ,y j ) are the edges ej The coordinates of the two vertices.

[0051] Step 2.3: Determine and merge small edges; traverse all edges e j , if L(e j )≤∈, it is considered that this edge is small and needs to be merged; at this time, merge e j Two vertices v i and v j , calculate the merged vertex coordinates v new :

[0052]

[0053] V new Add to V'. Update with v i and v j Connected edges, connect them to v new Delete v i and v j and edge e j .

[0054] Step 2.4: Update the edge set; traverse all edges e that have not been deleted j , if edge e j If both vertices of are in V′, then add the edge to E′.

[0055] Step 2.5: Return the result; return the updated vertex set V′ and edge set E′.

[0056] Through the above algorithm, unnecessary small features on the mold mounting surface can be effectively cleaned up to obtain a simpler two-dimensional model of the mold mounting surface.

[0057] Step 3: Project the boundary lines of each ply onto the mold mounting surface, and segment the mold mounting surface according to the projected boundary lines of each ply, divide the mold mounting surface into several areas, and divide the mold mounting surface into 2D grids based on the areas.

[0058] The boundary lines of each ply are projected onto the mold mounting surface along the normal direction. The projected boundary lines of each ply are then constructed into closed curves. The mold mounting surface is then divided into several regions based on each curve. Different regions can have different meshing requirements. A 2D grid (referred to as a grid) of a preset size is then created on the mold mounting surface according to the divided regions. Different 2D grids in different regions are distinguished by different colors.

[0059] Specifically, assuming the mold mounting surface is a parameterized surface S(u,v), where u and v are surface parameters, each point P on the boundary line of the ply needs to be projected onto the mold mounting surface.

[0060] For a point P(x, y, z) on the boundary line, its projection point P′(u, v) on the mold mounting surface can be calculated by following the steps 3.1 and 3.2.

[0061] Step 3.1: Calculate the normal vector of the mold mounting surface; assuming that the normal vector of the mold mounting surface near point P is N(u, v), it can be calculated by the partial derivative of the surface:

[0062]

[0063] in, and are the tangent vectors of the surface in the u and v directions respectively.

[0064] Step 3.2: Calculate the projection point; project from point P along the normal vector N(u, v) to the mold mounting surface. The following formula can be used:

[0065] P′(u,v)=Pt·N(u,v) (4);

[0066] Where t is a scalar, which represents the distance from point P along the normal vector projection to the mold mounting surface, which can be obtained by solving the following equation:

[0067] S(u, v)-P=t·N(u, v) (5);

[0068] This is a linear equation in t that can be solved numerically.

[0069] Assume that the projected boundary line consists of a series of points {P′1,P′2,...,P′ n}, the next step is to construct these points into a closed curve, which can be achieved by following the steps 3.3 and 3.4.

[0070] Step 3.3: Calculate the order of points; in order to construct a closed curve, the order of points needs to be determined. The following formula can be used to calculate the point P′ i and P′ j Distance between:

[0071]

[0072] Among them, (u i ,v i ) and (u j ,v j ) are points P′ i and P′ j Coordinates in parameter space.

[0073] Step 3.4: Construct a closed curve; find the shortest path connecting all points by using a minimum spanning tree algorithm (such as Prim's algorithm) or a traveling salesman problem (TSP) algorithm to construct a closed curve.

[0074] Next, the mold mounting surface needs to be segmented one by one according to each curve, and the mold mounting surface needs to be divided into several areas. This can be achieved by following the steps 3.5 below.

[0075] Step 3.5: Region division; Assume there are m closed curves {C1, C2, ..., C m}, the mold surface needs to be divided into several areas, then use the plane geometry method to divide each closed curve C i Considered as the boundary of a region, the area of ​​each region can be calculated by the following formula:

[0076]

[0077] Among them, n i It is curve C i The number of points on (u ij , v ij ) is curve C i The coordinates of the jth point on the graph;

[0078]

[0079] Through the above steps 3.1 to 3.5, the projection of the boundary lines of each layer in the composite material structure, the construction of the closed curve and the regional division of the mold surface can be achieved.

[0080] Step 4: Combine the layup information of all plies and stretch the 2D mesh layer by layer to generate a 3D finite element model of the composite structure.

[0081] The draping areas of each layer of material within a composite structure are not always identical, making it impossible to stretch them all at once. Therefore, each layer must be processed layer by layer. Composite structures can be complex geometries, and projection yields distinct boundary lines. The area enclosed by these boundary lines represents the draping area for that layer. Subsequently, all 2D meshes within each layer's boundary lines are selected for stretching.

[0082] Specifically, for a composite structural component, the draping areas of each ply are selected from the bottom up. The 2D mesh corresponding to the draping area is then stretched according to the ply thickness and angle of each ply until the thickness and angle of each ply are consistent with the actual ply thickness and angle. In other words, after selecting the draping area for each layer, the stretching process proceeds layer by layer from the bottom up, with the thickness and angle of each layer set to match the actual ply thickness and angle.

[0083] In step 4, the 2D grid can be stretched layer by layer using a grid stretching algorithm. The input of the grid stretching algorithm includes: 1) the boundary lines of each layer {B1, B2, ..., B n} and the 2D grid of the paving area enclosed by the boundary lines of each ply {P 2D}; 2) the thickness of each layer {t1, t2, ..., t n}t i and ply angles {θ1, θ2, ..., θ n}θ i The output of the mesh stretching algorithm is the stretched 3D mesh {P 3D}, representing the geometric shape of each ply. This requires processing the 2D mesh of each ply's corresponding coverage area from bottom to top. For each ply, the 2D mesh is stretched based on its ply thickness and layup angle, and the stretched mesh of each layer is saved for subsequent layer processing. The mesh stretching algorithm specifically includes steps 4.1 to 4.5.

[0084] Step 4.1: Initialize the 3D grid; convert the 2D grid {P 2D}Map to the z=0 plane of 3D space to obtain the initial 3D grid

[0085] Step 4.2: Select the covering area; for each layer i (from 1 to n), according to the boundary line B i , select all points in the 2D grid that lie within this boundary line

[0086] Step 4.3: Calculate the stretching direction; according to the ply angle θ of the i-th layer i , calculate the stretching direction vector d i :

[0087] d i =(d ix , d iy , d iz )=(cos(θ i ), sin(θ i ), 0) (8);

[0088] Where (d ix , d iy , d iz ) is the stretching direction vector d i Three components in the X, Y, and Z directions.

[0089] Step 4.4: Stretch the mesh; for each point Calculate the 3D coordinates after stretching

[0090] in is a point in the 2D grid that is within the boundary line of the i-th layer; t i is the ply thickness of the i-th layer.

[0091] Step 4.5: Update the 3D mesh; move the stretched points Add to the 3D mesh collection; save the stretching results of all layers as the final 3D mesh model, that is, the stretched mesh model.

[0092] Create a mesh set for the stretched mesh corresponding to each ply. Use the material parameter properties defined in step 1 to assign the corresponding material parameters to each mesh set to obtain a three-dimensional finite element model of the composite material structure, which is also a mesh model.

[0093] Composite structural components inherently exhibit the structural characteristics of laminates. To simulate the laminate structure and correctly assign material parameters and properties, the mesh division during finite element model creation must strictly correspond to the actual layup design. Before stretching the mesh, the boundary search function is used to search for the mesh boundaries of each user-selected layer. This boundary search function can be developed as a plug-in using software such as Python. When stretching the mesh, the ply set of the laminate is first established. The 2D mesh corresponding to the bottom-layer overlay area is obtained, also known as the element. The bottom-layer elements are then stretched. If the selected area is determined to be a missing layer or interlayer, an additional triangular transition mesh is generated outside the mesh boundary of the layer after stretching to prevent gaps within the model caused by missing layers. Furthermore, based on the obtained boundary elements, an adjacency relationship is used to find a circle of elements outside the boundary, namely the transition elements. The bottom element corresponding to the transition element is found using the Find Bottom Element function (developed using Python software). If the layer is the initial layer, the bottom element is the element of the current layer; if a layer is already stretched, the bottom element is the element stretched from the previous layer. The node information of the bottom unit and the top unit is obtained, the nodes are sorted according to the construction method specified by the unit, and the nodes are connected to finally generate transitional solid units, that is, a three-dimensional finite element model of the composite material structure is obtained.

[0094] Step 5: Perform curing deformation simulation based on the 3D finite element model of the composite structural part to predict deformation and defects during the curing molding process.

[0095] Based on the three-dimensional finite element model of the composite structural part, using simulation software such as Simcenter 3D and Abaqus to perform curing deformation simulation, it is possible to predict the structural deformation and natural defects that may occur in the composite structural part during the autoclave curing molding process.

[0096] In the past, when simulation software was used for simulation analysis, the establishment of the mesh model depended on the original geometric model, that is, the generation of the mesh model was to discretize the geometric model of the structural part into a mesh after importing it. Obviously, for large composite structural parts with complex internal layup structures, manually dividing the geometric model into layers of meshes is inefficient or even impossible. Therefore, developing a method for quickly establishing a mesh model of a composite structural part will effectively improve the simulation efficiency. The method described in this application is different from the previous method of first importing the geometric model of the composite structural part and then meshing the geometric model. The finite element model for curing deformation simulation is often less efficient. Instead, it fully combines the global layup information of the composite structural part, stretches from the bottom of the structural part upward, and generates a mesh model that is highly consistent with the layup design of the actual structural part, thereby realizing rapid modeling and simulation of the overall layup of the composite structural part.

[0097] The present application proposes a method for rapid modeling of the overall layup of a composite material structural part in composite material curing deformation simulation, which can improve the modeling efficiency of the finite element model of the composite material structural part. The method mainly includes: obtaining the layup information of all layups of the composite material structural part, projecting the boundary lines of each layup onto the mold surface, dividing the mold surface according to the projected boundary lines of each layer, dividing the mold surface into several areas, dividing the 2D grid on the mold surface by area, generating a two-dimensional model of the composite material from the 2D grid of the mold surface, and on this basis, combining the global layup information, stretching the 2D grid layer by layer, assigning each layer of grid material parameter attributes, layup thickness, and layup angle respectively, and finally generating a three-dimensional finite element model of the composite material structural part.

[0098] Generally speaking, the establishment of a finite element model during the simulation process needs to rely on the geometric model of the part (structural part). The geometric model of the part is first imported into the simulation software and then meshed. For large and complex laminated composite structural parts, there are a large number of missing layers and sandwich structures inside, which poses a challenge to how to quickly establish a composite structural mesh model that is highly consistent with the actual laminate design. Based on this, the present application fully combines the global laminate information, first divides the 2D mesh on the mold surface of the part, and then considers the laying area, layup thickness and layup angle of each layer of material inside the composite structural part, stretches the mesh layer by layer from bottom to top, and generates an additional circle of triangular meshes around the mesh boundary of the missing layer and sandwich area, so as to avoid gaps in the model due to the missing layer structure, and finally generates a three-dimensional finite element model of the composite structural part.

[0099] A specific embodiment of the method of the present application is provided below, including the following S1 to S5.

[0100] S1: Obtain the ply information of all plies inside the composite structure and the boundary lines of each ply; the ply information of all plies includes the material parameters, ply thickness, ply angle and covering area of ​​each ply.

[0101] The composite structural member of this embodiment is a simple flat plate with a dropped layer structure, which contains a total of 5 layers. The specific layer information is shown in Table 1.

[0102] Table 1 Global layup information of composite structural parts

[0103] Layer number Lamination materials Layer thickness Laying angle Covering area 1 AS4 / 8552 0.2mm 0° Area 1 2 AS4 / 8552 0.2mm 90° Area 1 3 AS4 / 8552 0.2mm 0° Area 1 4 AS4 / 8552 0.2mm 90° Area 2 5 AS4 / 8552 0.2mm 0° Area 1

[0104] In this embodiment, the specific material parameters of the AS4 / 8552 prepreg used are shown in Table 2.

[0105] Table 2AS4 / 8552 material parameters

[0106]

[0107] Set the material name of the single layer material according to Table 1 and Table 2, enter the material parameter properties required for curing deformation simulation, and add the material model of each layer to the material library.

[0108] S2: Obtain the mold model of the composite structural part and perform geometric processing to construct a two-dimensional model of the mold surface.

[0109] In this embodiment, the mold model and the layer loss boundary line of the composite material structure are as follows: Figure 2 The original mold model and layer loss boundary line are provided by the designer. Figure 2 The entire rectangular flat plate structure shown is the mold model, and the rectangle in the middle is the layer loss boundary line.

[0110] S3: Projecting the boundary lines of each ply onto the mold mounting surface, and dividing the mold mounting surface according to the projected boundary lines of each ply, dividing the mold mounting surface into a plurality of regions, and dividing a 2D grid on the mold mounting surface according to the regions.

[0111] Perform geometric processing on the mold model, construct a two-dimensional model of the mold mounting surface, project all the layer boundary lines onto the mold mounting surface, and segment the mold mounting surface according to the projected layer boundary lines, thereby dividing the mold mounting surface into several areas, and dividing the 2D grid on the mounting surface by area, such as Figure 3 In this embodiment, two areas are divided, where area 1 refers to Figure 3 All areas in the Figure 3 The inner rectangular area is the layer loss area. The mold film surface is divided into regions according to the projected boundary line. After dividing the grids, different colors are used to distinguish the grids in different areas.

[0112] S4: Combining the layup information of all plies, the 2D mesh is stretched layer by layer to generate a 3D finite element model of the composite structure.

[0113] The developed mesh stretching plug-in is called, and according to the global layup information, the covering areas of each layer are selected in sequence, namely area 1 and area 2. The 2D mesh is stretched layer by layer according to the layup information in Table 1 to generate a 3D finite element model cross-sectional view of the composite material structure as shown in the figure. Figure 4 shown.

[0114] S5: Perform curing deformation simulation based on a 3D finite element model of composite structural parts to predict deformation and defects during the curing molding process.

[0115] This application obtains the layup information of all layers of a composite structural part, projects the boundary lines of each layer onto the mold surface, divides the mold surface according to the projected boundary lines of each layer, divides the mold surface into several regions, and divides the 2D grid on the surface by region; based on the 2D grid of the mold surface, combined with the global layup information, the 2D grid is stretched layer by layer, and each layer of the grid is given material parameter properties, layup thickness, and layup angle, and finally a three-dimensional grid model of the composite structural part is generated. This application can generate a grid model that is highly consistent with the layup design of the actual structural part in the composite material curing deformation simulation. Its modeling efficiency is faster than the method of manually dividing the grid of the imported geometric model, which is of great significance to the engineering application of composite material curing deformation simulation.

[0116] In an exemplary embodiment, the present application also provides a computer device, which may be a server or a terminal. The computer device includes a processor, a memory, an input / output interface, and a communication interface. The processor, the memory, and the input / output interface are connected via a system bus, and the communication interface is connected to the system bus via the input / output interface. 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 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 via a network connection. When the computer program is executed by the processor, the composite material structural component curing deformation simulation method is implemented.

[0117] In an exemplary embodiment, the present application further provides a computer-readable storage medium having a computer program stored thereon, which implements the composite material structural component curing deformation simulation method when executed by a processor.

[0118] In an exemplary embodiment, the present application further provides a computer program product, including a computer program, which implements the composite material structural component curing deformation simulation method when executed by a processor.

[0119] It will be understood by those skilled in the art that all or part of the processes in the above-mentioned embodiment method can be completed by hardware related to computer program instructions, 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 process of the embodiment of the above-mentioned method. Among them, any reference to memory or other media in the embodiments provided in this application may include at least one of non-volatile and volatile memory. Non-volatile memory may 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 may 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).

[0120] It should be noted that the 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.

[0121] The technical features of the above embodiments can 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.

[0122] This document uses specific examples to illustrate the principles and implementation methods of this application. The description of the above examples is only intended to help understand the method and core concept of this application. At the same time, for those skilled in the art, based on the concept of this application, there may 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 simulating the curing deformation of a composite material structure, characterized in that: include: Obtain the layup information of all layers inside the composite structure and the boundary lines of each layer; the layup information of all layers includes the material parameters, layer thickness, layer angle and covering area of ​​each layer; Obtain the mold model of the composite structural part and perform geometric processing to construct a two-dimensional model of the mold surface; Projecting the boundary lines of each ply onto the mold mounting surface, and segmenting the mold mounting surface according to the projected boundary lines of each ply, dividing the mold mounting surface into several regions, and dividing the 2D grid on the mold mounting surface according to the regions; Combining the layup information of all layers, the 2D mesh is stretched layer by layer to generate a 3D finite element model of the composite structure; Perform curing deformation simulation based on the 3D finite element model of composite structural parts to predict deformation and defects during the curing molding process.

2. The composite material structural component curing deformation simulation method according to claim 1, characterized in that: The material parameters of each ply include thermal performance parameters of the composite material, mechanical parameters of the composite material and curing kinetic parameters of the composite material; the thermal performance parameters of the composite material include mass density, specific heat and thermal conductivity; the mechanical parameters of the composite material include Young's modulus, Poisson's ratio and thermal expansion coefficient; the curing kinetic parameters of the composite material include reaction order, activation energy and reaction frequency.

3. The composite material structural component curing deformation simulation method according to claim 1, characterized in that: The step of obtaining a mold model of a composite material structural component and performing geometric processing to construct a two-dimensional model of the mold mounting surface specifically includes: The mold model of the composite structural part is geometrically processed, only the upper surface of the mold model is retained and unnecessary lines on the surface are cleared to obtain a two-dimensional model of the mold mounting surface.

4. The composite material structural component curing deformation simulation method according to claim 3, characterized in that: The method of projecting the boundary lines of each ply onto the mold mounting surface, dividing the mold mounting surface into a plurality of regions according to the projected boundary lines of each ply, and dividing the mold mounting surface into 2D grids by region specifically includes: The boundary lines of each ply are projected onto the mold mounting surface along the normal direction of the mold mounting surface, and the projected boundary lines of each ply are constructed into closed curves. The mold mounting surface is divided one by one according to each curve, and the mold mounting surface is divided into several areas. 2D grids of preset sizes are divided on the mold mounting surface according to the areas.

5. The composite material structural component curing deformation simulation method according to claim 4, characterized in that: After the sub-areas are divided into 2D grids of preset sizes on the die attaching surface of the mold, the method further includes: Use different colors to distinguish different areas of the 2D grid.

6. The composite material structural component curing deformation simulation method according to claim 4, characterized in that: The method combines the layup information of all the plies and sequentially stretches the 2D mesh layer by layer to generate a 3D finite element model of the composite material structure, specifically including: Select the paving area of ​​each ply from bottom to top, and stretch the 2D mesh of the corresponding paving area according to the ply thickness and ply angle of each ply until the ply thickness and ply angle of each ply are consistent with the actual ply thickness and angle; A grid set is created for the stretched grid corresponding to each ply, and corresponding material parameters are assigned to each grid set to obtain a three-dimensional finite element model of the composite structural component.

7. The composite material structural component curing deformation simulation method according to claim 6, characterized in that: When selecting the covering area of ​​each ply, if the selected ply is a missing ply or a sandwich ply, an additional circle of triangular meshes is generated on the outer circle of the stretched mesh corresponding to the ply.

8. 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 composite material structural component curing deformation simulation method according to any one of claims 1 to 7.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for simulating curing deformation of a composite material structural component according to any one of claims 1 to 7 is implemented.

10. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the method for simulating curing deformation of a composite material structural component according to any one of claims 1 to 7 is implemented.

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