A laminated plate modeling method and device based on composite material ply design

Abstract

The application provides a laminated plate modeling method and device based on composite material layer design, physical characteristics of the composite material are comprehensively and accurately described through three levels of single-layer material, layer material and composite material, technical support is provided for linear static finite element simulation of the composite material structure, the problems of high modeling complexity and low modeling precision in the linear static finite element simulation of the composite material structure are solved, and the modeling efficiency is effectively improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of computer, more particularly, to a kind of laminated plate modeling method and device based on composite material layer design. BACKGROUND

[0002] Composite material is composed of different materials, and the internal structure is complex. In the linear static finite element simulation of composite material structure, the number of composite material laminated plate layers, the layer sequence is various, the assembly of multiple composite material grid model structures and composite material models needs to be completed, the modeling complexity is high, and the modeling precision is low. SUMMARY

[0003] Therefore, the present application provides a kind of laminated plate modeling method and device based on composite material layer design, solve the problem of high modeling complexity and low modeling precision in the linear static finite element simulation of composite material structure, effectively improve the modeling efficiency.

[0004] In order to achieve the above-mentioned application purpose, the specific technical solutions provided by the present application are as follows:

[0005] A kind of laminated plate modeling method based on composite material layer design, comprising:

[0006] Constructing a shell element laminated plate grid component model;

[0007] Constructing a single-layer material model of composite material;

[0008] Setting the layer angle and layer thickness of single-layer material, establishing the corresponding layer material model of the single-layer material model;

[0009] In response to composite material layer design instructions, generate a composite material model based on the layer material model;

[0010] Assemble the composite material model to the shell element laminated plate grid component model.

[0011] Optionally, the single-layer material model of composite material comprises:

[0012] Setting single-layer material classification and single-layer material name;

[0013] Generating single-layer material number;

[0014] Based on the stress-strain relationship of single-layer orthotropic material in the main direction of material, constructing the single-layer material model representing the elastic modulus, in-plane Poisson's ratio and in-plane shear modulus of single-layer material in different directions;

[0015] Storing the single-layer material model in a single-layer material file.

[0016] Optionally, the setting of the ply angle and ply thickness of the single-layer material, and the establishment of the ply material model corresponding to the single-layer material model, comprises:

[0017] Setting the ply name;

[0018] Generating the ply number;

[0019] Setting the ply angle and ply thickness of the single-layer material, and constructing the ply material model based on the single-layer material model;

[0020] Storing the ply material model into a ply material file.

[0021] Optionally, the generating of the composite material model based on the ply material model in response to the composite material ply design instruction, comprises:

[0022] Designing the order and number of ply materials in response to the composite material ply design instruction, the ply order being along the unit normal direction, and generating the composite material model, the composite material ply design instruction comprising: copy instruction, symmetry instruction, anti-symmetry instruction and delete instruction;

[0023] Generating the number of the composite material model;

[0024] Storing the composite material model in a composite material model file.

[0025] Optionally, the assembling of the composite material model to the shell unit laminate grid component model, comprises:

[0026] Assembling the number of the composite material model to the component of the shell unit laminate grid component model;

[0027] Exporting a calculation file to complete the creation of a composite material structure finite element calculation file.

[0028] A laminate modeling device based on composite material ply design, comprising:

[0029] A grid component model construction unit for constructing a shell unit laminate grid component model;

[0030] A single-layer material model construction unit for constructing a single-layer material model of a composite material;

[0031] A ply material model construction unit for setting the ply angle and ply thickness of the single-layer material, and establishing the ply material model corresponding to the single-layer material model;

[0032] A composite material model generation unit for generating a composite material model based on the ply material model in response to a composite material ply design instruction;

[0033] The model assembly unit is used to assemble the composite material model to the shell unit laminate mesh component model.

[0034] Optionally, the single-layer material model building unit is specifically used for:

[0035] Set the single-layer material category and single-layer material name;

[0036] Generate single-layer material numbers;

[0037] Based on the stress-strain relationship of a single-layer orthotropic material in the principal direction of the material, a single-layer material model is constructed to represent the elastic modulus, in-plane Poisson's ratio, and in-plane shear modulus of the single-layer material in different directions.

[0038] The single-layer material model is stored in a single-layer material file.

[0039] Optionally, the layup material model building unit is specifically used for:

[0040] Set the ply name;

[0041] Generate ply numbers;

[0042] Set the ply angle and ply thickness of the single-layer material, and construct the ply material model based on the single-layer material model;

[0043] The ply material model is stored in a ply material file.

[0044] Optionally, the composite material model generation unit is specifically used for:

[0045] In response to composite material layup design instructions, the sequence and number of layers of the layup materials are designed, with the layup sequence along the unit normal direction, to generate the composite material model. The composite material layup design instructions include: copy instruction, symmetry instruction, antisymmetry instruction, and deletion instruction.

[0046] Generate a number for the composite material model;

[0047] The composite material model is stored in a composite material model file.

[0048] Optionally, the model assembly unit is specifically used for:

[0049] Assign the number of the composite material model to the components of the shell unit laminate mesh component model;

[0050] Export the calculation file to complete the creation of the finite element calculation file for the composite material structure.

[0051] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0052] The application discloses a laminated plate modeling method and device based on composite material ply design, which comprehensively and accurately describes physical properties of the composite material through three levels of single-layer material, ply material and composite material, provides technical support for linear static finite element simulation of the composite material structure, solves the problems of high modeling complexity and low modeling accuracy in the linear static finite element simulation of the composite material structure, and effectively improves modeling efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0053] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the provided drawings.

[0054] Figure 1 A flowchart of the laminated plate modeling method based on the composite material ply design is disclosed in the embodiments of the present application.

[0055] Figure 2 A composite material ply design interface diagram is disclosed in the embodiments of the present application.

[0056] Figure 3 A composite material ply direction diagram is disclosed in the embodiments of the present application.

[0057] Figure 4 A composite material ply diagram is disclosed in the embodiments of the present application.

[0058] Figure 5 A structure diagram of the laminated plate modeling device based on the composite material ply design is disclosed in the embodiments of the present application. DETAILED DESCRIPTION

[0059] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the present application.

[0060] The application discloses a laminated plate modeling method and device based on composite material ply design, which comprehensively and accurately describes physical properties of the composite material through three levels of single-layer material, ply material and composite material, effectively improves modeling efficiency.

[0061] Please refer to Figure 1The embodiment of the application discloses a laminated plate modeling method based on composite material layer design, and specifically comprises the following steps:

[0062] S101: a shell element laminated plate grid component model is constructed;

[0063] In the finite element method, a composite material structure is simulated by a shell element (triangle or quadrilateral) grid. In a real composite material structure, multiple composite materials can be included. According to the different composite materials, multiple grid components are divided in the finite element.

[0064] Specifically, the shell element laminated plate grid component model including component numbers, component names and element types can be constructed by using any existing method, and is stored into a component file.

[0065] S102: a single-layer material model of the composite material is constructed;

[0066] The single-layer material model of the composite material is constructed, first, the shell element laminated plate grid component model is set, and a single-layer material number is generated, then based on the stress-strain relationship of the single-layer orthotropic material in the material principal direction, a single-layer material model representing the elastic modulus, in-plane Poisson's ratio and in-plane shear modulus of the single-layer material in different directions is constructed, and in order to manage, the single-layer material model is stored in a single-layer material file.

[0067] It should be noted that a real composite material structure needs multiple single-layer materials, and a plurality of single-layer material models need to be constructed.

[0068] A laminated plate is a structural unit composed of two or more simple laminates bonded together as a whole, a single-layer plate is a basic unit of a laminated plate or a layered structure, the arrangement of the material principal direction of each single layer enables the structural element to bear loads in several directions, and the macroscopic mechanical study of the single-layer plate is the basis for analyzing the laminated structure. The material, thickness and elastic principal direction of each single layer of the laminated plate can be different, and by appropriately changing these parameters, a structural element that can most effectively bear a specific external load can be designed, which is one of the advantages of the composite laminated plate.

[0069] A laminated plate composed of single layers with different physical properties and geometric sizes has the most general anisotropic properties, on the one hand, the laminated plate does not necessarily have a certain principal direction, and on the other hand, such a laminated plate has objective non-uniformity and discontinuity of mechanical properties in the thickness direction, which makes the mechanical analysis of the laminated plate more complex. The application can quickly predict the mechanical properties of the laminated plate under the condition that the properties of the single layer are known.

[0070] In a plane stress state, the stress-strain relationship of a single-layer orthotropic material in the material principal direction is:

[0071]

[0072] wherein:

[0073] σ1 is the stress in the principal direction 1 of the material;

[0074] σ2 is the stress in the principal direction 2 of the material;

[0075] τ 12 is the in-plane shear stress in the principal directions 1 and 2 of the material;

[0076] ∈1 is the strain in the principal direction 1 of the material;

[0077] ∈2 is the strain in the principal direction 2 of the material;

[0078] γ 12 is the in-plane shear strain in the principal directions 1 and 2 of the material.

[0079]

[0080] Q 66 = G 12

[0081] E1 is the longitudinal Young's modulus, i.e. the elastic modulus in the above-mentioned 1 direction;

[0082] E2 is the transverse Young's modulus, i.e. the elastic modulus in the above-mentioned 2 direction;

[0083] v 12 , v 21 is the in-plane Poisson's ratio;

[0084] G 12 is the in-plane shear modulus;

[0085] E1, E2, v 12 , G 12 constitute the input parameters of the single-layer material model, i.e. the single-layer material model represents the elastic modulus, the in-plane Poisson's ratio and the in-plane shear modulus of the single-layer material in different directions.

[0086] The single-layer material model has a unique number and is stored in a single-layer material file.

[0087] S103: setting the ply angle and ply thickness of the single-layer material, and establishing a ply material model corresponding to the single-layer material model;

[0088] To construct the ply material model, first, the ply name needs to be set and the ply number is generated, the ply angle and ply thickness of the single-layer material are set, and the ply material model is constructed on the basis of the single-layer material model.

[0089] Specifically:

[0090] The transformation equation of stress in the xy coordinate system is:

[0091]

[0092] wherein:

[0093] θ is the angle from the x-axis to the 1-axis, which is one of the input parameters of the model of the ply material;

[0094] σ x is the stress in the x direction in the xy coordinate system;

[0095] σ y is the stress in the y direction in the xy coordinate system;

[0096] τ xy is the shear stress in the xy coordinate system.

[0097] The stress in the single-layer plane in any coordinate system is:

[0098]

[0099] wherein:

[0100] ∈ x is the strain in the x direction in the xy coordinate system;

[0101] ∈ y is the strain in the y direction in the xy coordinate system;

[0102] γ xy is the engineering shear strain in the xy coordinate system.

[0103]

[0104]

[0105]

[0106]

[0107]

[0108]

[0109] wherein, the matrix represents the transformation inverse matrix instead of the two-dimensional matrix Q ij .

[0110] The stress-strain relationship of the k-th layer of the multi-layer laminate is:

[0111]

[0112] ​Assume that the laminate is composed of many single layers bonded well together, and that the bond is very thin and has no shear deformation, i.e. the displacement on both sides of the single layer boundary is continuous, and there is no interlayer slippage. Thus, the laminate is equivalent to a single layer with very special properties, but still acts like a single layer of material; assume that an initial straight line perpendicular to the middle surface of the laminate remains straight and perpendicular to the middle surface after the laminate is subjected to tension and bending, and that the normal to the middle surface remains straight and perpendicular to the middle surface after deformation, which is equivalent to ignoring the shear strain in the plane perpendicular to the middle surface:

[0113] γ xz = γ yz = 0

[0114] In the xyz coordinate system, γ xz is the engineering shear strain in the xz plane;

[0115] In the xyz coordinate system, γ yz is the engineering shear strain in the yz plane.

[0116] According to the Kirchhoff-Love hypothesis, for small strain (linear elasticity), the strain is determined by the displacement as follows:

[0117]

[0118] U = u(x, y, z), v = (x, y, z), w = (x, y, z) are the displacements in the x, y, z directions.

[0119]

[0120] u o , v o , w o represent the middle surface displacement components.

[0121] The middle surface strain is:

[0122]

[0123] The middle surface curvature is:

[0124]

[0125] The strain of the laminate thickness is linearly varying, and the stress of the kth layer is expressed in terms of the middle surface strain and curvature of the laminate as follows:

[0126]

[0127] The resultant force and the resultant moment acting on the laminate are obtained by integrating the stress on each single layer along the thickness of the laminate:

[0128]

[0129] t is the single layer thickness, which is one of the input parameters of the layer material;

[0130] N x represents the resultant force, M x represents the resultant moment.

[0131] S104: In response to the composite material layer design instruction, generate a composite material model based on the layer material model;

[0132] The composite material layer design instruction includes: copy instruction, symmetry instruction, anti-symmetry instruction and delete instruction, the copy instruction is used to add the same layer material as the current layer material, and the delete instruction is used to delete the current layer material.

[0133] Referring to Figure 2 The composite material layer design interface diagram shown in the figure, the user can design the order and number of layers of the layer material by clicking each composite material layer design instruction in the function area, so as to ensure the consistency with the real layer order. The layer order is along the unit normal direction, the composite material model is generated, and then the number of the composite material model is generated. In order to facilitate management, the composite material model is stored in the composite material model file.

[0134] Specifically:

[0135] Referring to Figure 3 The composite material layer diagram shown in the figure, the total resultant force and resultant moment on the N-layer laminated plate are defined as:

[0136]

[0137]

[0138] The strain and curvature expressions are brought in, and the resultant force and resultant moment calculation formula is as follows:

[0139]

[0140]

[0141] Where, A ij is the tensile stiffness, B ij is the coupling stiffness, D ij is the bending stiffness.

[0142]

[0143] Where, Z k represents the thickness of the first k layer of layer material.

[0144] The above is a composite material model required for finite element analysis of a composite material structure according to a composite material laminate theory.

[0145] S105: Assemble the composite material model to the shell element laminate grid component model.

[0146] In the finite element method, the composite material model also needs to be assembled to the grid as a carrier, so as to represent a complete composite material structure.

[0147] According to the actual requirements of the composite material structure, the number of the composite material model is assembled to the component of the shell element laminate grid component model, and after the assembly is completed, the composite material layer sequence is as shown in Figure 4 The shell element grid element coordinate system (x, y, z) is from -t / 2 to t / 2. Figure 4 There are 1-6 layers of laying. The neutral surface of the shell element is the reference for the layer.

[0148] Finally, the calculation file is derived, and the creation of the finite element calculation file of the composite material structure is completed.

[0149] It can be seen that the laminated plate modeling method based on the composite material layer design disclosed in the embodiment comprehensively and accurately describes the physical properties of the composite material through three levels of single-layer material, layer material and composite material, provides technical support for the linear static finite element simulation of the composite material structure, solves the problems of high modeling complexity and low modeling accuracy in the linear static finite element simulation of the composite material structure, and effectively improves the modeling efficiency.

[0150] Based on the laminated plate modeling method based on the composite material layer design disclosed in the above embodiment, the embodiment discloses a laminated plate modeling device based on the composite material layer design. Please refer to Figure 5 The device comprises:

[0151] The grid component model construction unit 501 is configured to construct a shell element laminate grid component model.

[0152] The single-layer material model construction unit 502 is configured to construct a single-layer material model of the composite material.

[0153] The layer material model construction unit 503 is configured to set the layer angle and layer thickness of the single-layer material, and establish a layer material model corresponding to the single-layer material model.

[0154] The composite material model generation unit 504 is configured to generate a composite material model based on the layer material model in response to a composite material layer design instruction.

[0155] The model assembling unit 505 is configured to assemble the composite material model to the shell element laminate grid component model.

[0156] Optionally, the single-layer material model constructing unit 502 is specifically configured to:

[0157] set a single-layer material classification and a single-layer material name;

[0158] generate a single-layer material number;

[0159] construct the single-layer material model representing the elastic modulus, the in-plane Poisson's ratio and the in-plane shear modulus of the single-layer material in different directions based on the stress-strain relationship of the single-layer orthotropic material in the material principal direction;

[0160] store the single-layer material model in a single-layer material file.

[0161] Optionally, the ply material model constructing unit 503 is specifically configured to:

[0162] set a ply name;

[0163] generate a ply number;

[0164] set a ply angle and a ply thickness of the single-layer material, and construct the ply material model based on the single-layer material model;

[0165] store the ply material model in a ply material file.

[0166] Optionally, the composite material model generating unit 504 is specifically configured to:

[0167] generate the composite material model in response to a composite material ply design instruction, the ply sequence and the number of layers of the ply material being designed, the ply sequence being along the element normal direction, the composite material ply design instruction including a copy instruction, a symmetric instruction, an anti-symmetric instruction and a delete instruction;

[0168] generate a number of the composite material model;

[0169] store the composite material model in a composite material model file.

[0170] Optionally, the model assembling unit 505 is specifically configured to:

[0171] assemble the number of the composite material model to a component of the shell element laminate grid component model;

[0172] export a calculation file to complete the creation of a composite material structure finite element calculation file.

[0173] The embodiment discloses a laminated plate modeling device based on composite material layer design, which comprehensively and accurately describes the physical characteristics of the composite material through three levels of single-layer material, layer material and composite material, provides technical support for linear static finite element simulation of the composite material structure, solves the problems of high modeling complexity and low modeling accuracy in the linear static finite element simulation of the composite material structure, and effectively improves the modeling efficiency.

[0174] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the difference from other embodiments, and the same or similar parts between the various embodiments can be referred to each other. For the device disclosed by the embodiments, since it corresponds to the method disclosed by the embodiments, the description is relatively simple, and the related parts can be referred to the method part.

[0175] It should also be noted that the relative terms, such as first and second, are used herein only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the terms "include", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or device. Without more limitations, the element defined by the statement "including a" does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0176] The steps of the method or algorithm described in combination with the embodiments disclosed herein can be implemented directly by hardware, software modules executed by a processor, or a combination of the two. The software modules can be placed in random access memory (RAM), memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0177] The above-described various embodiments can be combined arbitrarily, and the above-described description of the disclosed embodiments can be replaced or combined with the features described in each embodiment in the specification, so that those skilled in the art can implement or use the present application.

[0178] The foregoing description of the disclosed embodiments enables a person skilled in the art to make or use the application. Modifications of these embodiments will occur to persons of skill in the art, and that the appended claims are intended to cover all such modifications that do not depart from the true spirit and scope of the application. Therefore, the application is not limited to the embodiments shown but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for modeling laminates based on composite material layup design, characterized in that, include: Construct a shell-unit laminated plate mesh component model; Multiple single-layer material models of composite materials are constructed. The construction process of the single-layer material model includes: based on the stress-strain relationship of the single-layer orthotropic material in the principal direction of the material, constructing the single-layer material model representing the elastic modulus, in-plane Poisson's ratio and in-plane shear modulus of the single-layer material in different directions. Set the ply angle and ply thickness of the single-layer material, and build a ply material model corresponding to the single-layer material model based on the single-layer material model; In response to the composite material layup design instructions, a composite material model is generated based on the layup material model; The composite material model is assembled onto the shell unit laminate mesh component model.

2. The method according to claim 1, characterized in that, The single-layer material model for constructing the composite material also includes: Set the single-layer material category and single-layer material name; Generate single-layer material numbers; The single-layer material model is stored in a single-layer material file.

3. The method according to claim 2, characterized in that, Also includes: Set the ply name; Generate ply numbers; The ply material model is stored in a ply material file.

4. The method according to claim 1, characterized in that, The process of generating a composite material model based on the layup material model in response to the composite material layup design instruction includes: In response to composite material layup design instructions, the sequence and number of layers of the layup materials are designed, with the layup sequence along the unit normal direction, to generate the composite material model. The composite material layup design instructions include: copy instruction, symmetry instruction, antisymmetry instruction, and deletion instruction. Generate a number for the composite material model; The composite material model is stored in a composite material model file.

5. The method according to claim 4, characterized in that, Assemble the composite material model onto the shell unit laminate mesh component model, including: Assign the number of the composite material model to the components of the shell unit laminate mesh component model; Export the calculation file to complete the creation of the finite element calculation file for the composite material structure.

6. A laminate modeling device based on composite material layup design, characterized in that, include: Mesh component model building unit, used to build shell element laminate mesh component models; A single-layer material model building unit is used to build multiple single-layer material models of composite materials. The construction process of the single-layer material model includes: based on the stress-strain relationship of the single-layer orthotropic material in the principal direction of the material, constructing the single-layer material model representing the elastic modulus, in-plane Poisson's ratio and in-plane shear modulus of the single-layer material in different directions. The ply material model building unit is used to set the ply angle and ply thickness of a single-layer material, and to build a ply material model corresponding to the single-layer material model based on the single-layer material model. A composite material model generation unit is used to generate a composite material model based on the layup material model in response to a composite material layup design instruction. The model assembly unit is used to assemble the composite material model to the shell unit laminate mesh component model.

7. The apparatus according to claim 6, characterized in that, The single-layer material model building unit is also used for: Set the single-layer material category and single-layer material name; Generate single-layer material numbers; The single-layer material model is stored in a single-layer material file.

8. The apparatus according to claim 7, characterized in that, The layered material model building unit is also used for: Set the ply name; Generate ply numbers; The ply material model is stored in a ply material file.

9. The apparatus according to claim 6, characterized in that, The composite material model generation unit is specifically used for: In response to composite material layup design instructions, the sequence and number of layers of the layup materials are designed, with the layup sequence along the unit normal direction, to generate the composite material model. The composite material layup design instructions include: copy instruction, symmetry instruction, antisymmetry instruction, and deletion instruction. Generate a number for the composite material model; The composite material model is stored in a composite material model file.

10. The apparatus according to claim 9, characterized in that, The model assembly unit is specifically used for: Assign the number of the composite material model to the components of the shell unit laminate mesh component model; Export the calculation file to complete the creation of the finite element calculation file for the composite material structure.

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