Full-size finite element modeling method for multi-angle plain weave composite
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- HARBIN INST OF TECH
- Filing Date
- 2025-01-21
- Publication Date
- 2026-07-21
AI Technical Summary
Existing finite element modeling methods for multi-angle plain weave composite materials lack precise division of warp and weft regions, resulting in inaccurate damage analysis and high computational complexity, making it difficult to handle large-size models.
By establishing a standard for dividing warp and weft regions in a global coordinate system, traversing the center points of the units, creating unit sets for the warp and weft regions respectively, assigning them their respective material properties, and performing finite element simulation calculations.
It enables accurate analysis of material damage, reduces computational complexity and resource consumption, and improves simulation accuracy and efficiency, making it suitable for structural performance analysis of large-size composite materials.
Smart Images
Figure CN120068516B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a modeling method, specifically a full-size finite element modeling method for multi-angle plain weave composite materials. This invention belongs to the field of composite material simulation and modeling technology. Background Technology
[0002] Plain-weave lay-up composites are a unique structure formed by the interweaving of warp and weft fiber bundles. This material has important applications in the composite field due to its excellent mechanical properties resulting from its unique weave structure. However, the complex interweaving of the fiber bundles presents numerous challenges to traditional finite element modeling methods when dealing with this material.
[0003] Currently, unit cell modeling is commonly used for finite element modeling of plain weave composite materials. This method selects a periodic region of the plain weave structure, constructs geometric models of the fiber bundles and matrix separately, and then divides these models into fine meshes before applying periodic boundary conditions to obtain homogenized material parameters. However, unit cell modeling reveals significant limitations when applied to full-size modeling of specimens. First, due to the high complexity of the woven structure of plain weave composite materials, a large number of meshes are required to accurately describe the geometric features of the structure when performing full-size modeling. This leads to a significant increase in computational load, especially when the material size is large, the number of meshes in the model becomes enormous, significantly increasing the computational difficulty and even exceeding the capabilities of conventional computing resources. Second, for plain weave structures with multiple angled layups, it is difficult to find a uniform periodic region suitable for the entire structure. The yarn orientation of plain weave layups varies, and traditional unit cell modeling methods cannot effectively handle the yarn distribution characteristics under multiple orientation layups. Therefore, although this type of method can obtain certain homogenized parameters within small-sized periodic regions, its applicability is limited in practical applications, especially for large-size models.
[0004] Furthermore, to simplify calculations, existing full-scale finite element modeling methods typically mesh directly based on the specimen's geometric model and assign homogenization parameters to the mesh. While this method reduces the number of meshes and computational complexity to some extent, it fails to distinguish between warp and weft yarns in plain weave structures. This simplification ignores different damage modes between yarns, especially microscopic damage that may occur during the use of composite materials. Under this modeling method, the differences in mechanical behavior between warp and weft yarns cannot be accurately described, resulting in insufficient accuracy in damage behavior analysis.
[0005] Therefore, existing full-size finite element modeling methods for multi-angle plain weave composite materials lack precise division of warp and weft regions, making it difficult to accurately analyze material damage. Summary of the Invention
[0006] To overcome the limitations of existing modeling methods and address the problem that existing full-size finite element modeling methods for multi-angle plain weave composite materials lack precise division of warp and weft yarn regions, making it difficult to accurately analyze material damage, this invention proposes a full-size finite element modeling method for multi-angle plain weave composite materials.
[0007] The technical solution adopted by the present invention to solve the above problems is as follows:
[0008] The full-size finite element modeling method for multi-angle plain-weave composite materials described in this invention includes the following steps:
[0009] Step 1: Establish a geometric model based on the actual dimensions of the specimen;
[0010] Step 2: Calculate the coordinates of the center point of each cell in the mesh model;
[0011] Step 3: Establish the division criteria for warp and weft yarn regions in the model's global coordinate system;
[0012] Step 4: Traverse the center point coordinates of all units, and combine them with the boundary point coordinates of the warp and weft yarn areas to determine the region to which each unit belongs;
[0013] Step 5: Based on the region to which the unit belongs, create two unit sets for each layup, storing units whose center point is located in the warp yarn region and units in the weft yarn region, respectively;
[0014] Step 6: Assign corresponding material properties and material orientations to the units in the warp and weft regions of each layup, and continue with subsequent finite element simulation calculations.
[0015] Furthermore, in step one, the established geometric model is divided into meshes so that each layup contains upper and lower meshes in the thickness direction, and the warp and weft yarn regions in the upper and lower meshes are in opposite positions.
[0016] Furthermore, in step two, the formula for calculating the coordinates of the unit center point is as follows:
[0017]
[0018] Where n is the number of unit nodes, x i ,y i ,z i These are the coordinates of the unit node.
[0019] Furthermore, in step three, for each layer of plain weave composite material, an initial point (x0, y0) is first set. The warp and weft yarn regions of the two units corresponding to this layer are in opposite positions. Formula 2 is used to generate the center point coordinates of the warp and weft yarn regions of the first layer unit respectively, and Formula 3 is used to generate the center point coordinates of the warp and weft yarn regions of the second layer unit respectively.
[0020]
[0021]
[0022] Where i = 0, 1, 2, ..., N rows -1, j = 0, 1, 2, ..., N cols -1, N rows and N cols These are the number of arrays of plain-textured unit cells along the x and y directions, respectively; (x wrap1 ,y wrap1 ),(x wrap2 ,y wrap2 (x) is the set of coordinates of the warp region center of the first unit corresponding to each layer of plain weave composite material, (x) weft1 ,y weft1 ),(x weft2 ,y weft2 ) is the set of coordinates of the center of the weft yarn region of the first layer unit, and s is the yarn width in the plain weave structure.
[0023] Furthermore, in step four,
[0024] Based on the center point coordinates of the warp and weft regions, the boundary point coordinates of the warp and weft regions are calculated using Formula 4:
[0025]
[0026] For ply directions that are inconsistent with the model's global coordinate system, the coordinates of the warp and weft yarn boundary points under that ply are calculated using Formula 5:
[0027]
[0028] Where θ is the ply angle, (x k ,y k (x′) represents the coordinates of the boundary points of the warp and weft yarn regions of the layup, where the layup direction is consistent with the global coordinate system. k ,y′ k ) represents the coordinates of the boundary points of the warp and weft yarn regions of the layup where the layup direction is inconsistent with the global coordinate system, k = 1, 2, 3, 4.
[0029] Traverse the coordinates of the center point of the unit obtained in step 2, and use the coordinates of the boundary of the yarn area obtained in steps 4 and 5 to determine the yarn area where the center point of each unit is located in turn using formula 6.
[0030]
[0031] Where (x) i ,y i ), i = 1, 2, 3, 4 are the coordinates of the boundary points of the yarn region, (x p ,y p ) represents the coordinates of the center point of the unit. When the signs of cross(1,2,p), cross(2,3,p), cross(3,4,p) and cross(4,1,p) are the same, the unit is assigned to the yarn region.
[0032] The beneficial effects of this invention are:
[0033] 1. This invention establishes a more realistic and accurate full-size finite element model by precisely distinguishing the warp and weft regions in a plain weave structure. This model can comprehensively capture yarn damage information in the material and structure during simulation, including local damage, fiber breakage, and interlayer slippage, thereby significantly improving the accuracy of damage analysis, especially in performance prediction under high loads and complex loads, where it has higher reliability.
[0034] 2. The modeling method employed in this invention not only improves simulation accuracy but also effectively reduces the number of redundant elements in the mesh generation. Through reasonable region partitioning and simplified mesh generation, the computational complexity and time cost are significantly reduced, ensuring the model's high efficiency in large-scale finite element simulations. Compared to traditional methods, this invention greatly reduces computational resource consumption and improves computational efficiency, making it particularly suitable for the simulation analysis of large-size, multi-layered composite materials.
[0035] 3. The method of this invention has strong adaptability and can handle various plain-weave ply composite materials with different ply angles and yarn arrangements. Whether in aerospace, automotive manufacturing, or wind power generation industries, this method can be used for precise structural performance analysis, optimization of material design, and improvement of the overall performance and safety of the structure. Attached Figure Description
[0036] Figure 1 This is a flowchart of a full-size finite element modeling method for multi-angle plain layup composite materials proposed in this invention;
[0037] Figure 2 This is a schematic diagram showing the distribution of warp and weft yarn regions in each layup of the present invention;
[0038] Figure 3This is a schematic diagram showing the division of warp and weft yarn regions corresponding to the two mesh layers in the 0° layup of the plain weave perforated specimen, as described in this embodiment of the invention.
[0039] Figure 4 This is a schematic diagram showing the division of warp and weft yarn regions corresponding to the two layers of mesh in a 45° layup of a plain weave perforated specimen, as described in an embodiment of the present invention. Detailed Implementation
[0040] Detailed Implementation: This implementation method is described in conjunction with the accompanying drawings. This method establishes a full-size finite element model for a plain ply open test specimen with a ply angle of [0° / 45°]8. The process is as follows: Figure 1 As shown, it includes the following steps:
[0041] Step 1: Based on the actual dimensions of the specimen, establish its geometric model. In the finite element simulation software, mesh the composite material according to the number of layers, ensuring that each layer contains two meshes in the thickness direction. Create an element set for each layer and export the node, mesh, and element set information as a text file.
[0042] Step 2: Use a Python program to read the exported text file, iterate through each cell, and calculate the coordinates of its center point. The formula for calculating the coordinates of the cell center point is as follows:
[0043]
[0044] Where n is the number of unit nodes, x i ,y i ,z i These are the coordinates of the unit node.
[0045] Step 3: For each layup, set an initial point on the plane and calculate the coordinates of the boundary points of the warp and weft yarn areas respectively. Each layup unit is divided into upper and lower layers, and the warp and weft yarn areas of the upper and lower layers are in opposite positions. For example... Figure 2 As shown, this is a schematic diagram of the warp and weft yarn distribution areas of the two-layer unit corresponding to each layup.
[0046] For each layer of plain weave composite material, first set an initial point (x0, y0). The warp and weft areas of the two units corresponding to this layer are in opposite positions. Formula 2 is used to generate the center point coordinates of the warp and weft areas of the first unit, and Formula 3 is used to generate the center point coordinates of the warp and weft areas of the second unit.
[0047]
[0048]
[0049] Where i = 0, 1, 2, ..., Nrows -1, j = 0, 1, 2, ..., N cols -1, N rows and N cols These are the number of arrays of plain-textured unit cells along the x and y directions, respectively; (x wrap1 ,y wrap1 ),(x wrap2 ,y wrap2 (x) is the set of coordinates of the warp region center of the first unit corresponding to each layer of plain weave composite material, (x) weft1 ,y weft1 ),(x weft2 ,y weft2 ) is the set of coordinates of the center of the weft yarn region of the first layer unit, and s is the yarn width in the plain weave structure.
[0050] Step 4: Based on the center point coordinates of the warp and weft areas, calculate the boundary point coordinates of the warp and weft areas using Formula 4:
[0051]
[0052] Step 5: For ply directions that are inconsistent with the model's global coordinate system, calculate the coordinates of the warp and weft yarn boundary points under that ply using Formula 5:
[0053]
[0054] Where θ is the ply angle, (x k ,y k (x′) represents the coordinates of the boundary points of the warp and weft yarn regions of the layup, where the layup direction is consistent with the global coordinate system. k ,y′ k ) represents the coordinates of the boundary points of the warp and weft yarn regions of the layup where the layup direction is inconsistent with the global coordinate system, k = 1, 2, 3, 4.
[0055] The results of the 0° ply area division are as follows Figure 3 As shown, the zoning results for the 45° ply are as follows: Figure 4 As shown.
[0056] Step 6: Iterate through the coordinates of the unit center points obtained in Step 2, and use the yarn region boundary coordinates obtained in Steps 4 and 5 to determine the yarn region where the center point of each unit is located using Formula 6.
[0057]
[0058] Where (x) i ,y i ), i = 1, 2, 3, 4 are the coordinates of the boundary points of the yarn region, (x p ,y p) represents the coordinates of the center point of the unit. When the signs of cross(1,2,p), cross(2,3,p), cross(3,4,p) and cross(4,1,p) are the same, the unit is assigned to the yarn region.
[0059] Step 7: Create two element sets for each layup in the text file, storing elements centered on the warp and weft regions respectively. Then, re-import the text file into the finite element simulation software, assigning different material properties and orientations to the warp and weft regions of each layup, and continue with subsequent finite element simulation calculations.
[0060] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent substitutions, and improvements made to the above embodiments without departing from the scope of the present invention, based on the technical essence of the present invention and within the spirit and principles of the present invention, shall still fall within the protection scope of the present invention.
Claims
1. A full-size finite element modeling method for multi-angle plain-weave ply composite materials, characterized in that, The method includes the following steps: Step 1: Establish a geometric model based on the actual dimensions of the specimen; Step 2: Calculate the coordinates of the center point of each cell in the mesh model; Step 3: Establish the division criteria for warp and weft yarn regions in the model's global coordinate system; Step 4: Traverse the center point coordinates of all units, and combine them with the boundary point coordinates of the warp and weft yarn areas to determine the region to which each unit belongs; Step 5: Based on the region to which the unit belongs, create two unit sets for each layup, storing units whose center point is located in the warp yarn region and units in the weft yarn region, respectively; Step 6: Assign corresponding material properties and material orientations to the units in the warp and weft regions of each layup, and continue with subsequent finite element simulation calculations; In step one, the established geometric model is divided into grids so that each layer contains two grids, upper and lower, in the thickness direction, and the warp and weft yarn regions in the upper and lower grids are in opposite positions. In step three, for each layer of plain weave composite material, an initial point is first set. The two units corresponding to this layer have their warp and weft areas in opposite positions. Formula 2 is used to generate the center point coordinates of the warp and weft areas of the first layer unit, and Formula 3 is used to generate the center point coordinates of the warp and weft areas of the second layer unit. (2) (3) in , , and They are the plain-structured unit cells along Number of arrays in each direction; It is the set of coordinates of the warp area center of the first unit corresponding to each layer of plain weave composite material. It is the set of coordinates of the center of the weft yarn region of the first layer unit. It refers to the yarn width in a plain weave structure; In step four, Based on the center point coordinates of the warp and weft regions, the boundary point coordinates of the warp and weft regions are calculated using Formula 4: (4) For ply directions that are inconsistent with the model's global coordinate system, the coordinates of the warp and weft yarn boundary points under that ply are calculated using Formula 5: (5) in It's the ply angle. These are the coordinates of the boundary points of the warp and weft yarn regions of the layup that are aligned with the global coordinate system. These are the coordinates of the boundary points of the warp and weft yarn regions of a ply layup whose direction is inconsistent with the global coordinate system. ; Traverse the coordinates of the center point of the unit obtained in step 2, and use the coordinates of the boundary of the yarn area obtained in steps 4 and 5 to determine the yarn area where the center point of each unit is located in turn using formula 6. (6) in These are the coordinates of the boundary points of the yarn region. These are the coordinates of the unit center point, when If the symbols are the same, the unit is assigned to the yarn region.
2. The full-size finite element modeling method for multi-angle plain-weave ply composite materials according to claim 1, characterized in that, In step two, the formula for calculating the coordinates of the unit center point is as follows: (1) Where n is the number of unit nodes. These are the coordinates of the unit node.