Model construction and simulation method and device of woven composite material and storage medium

Abstract

The invention discloses a model construction and simulation method and device for a woven composite material and a storage medium, and the method comprises the steps: endowing a fiber bundle model and a porous matrix model with material performances at a microscopic scale, then applying a multi-physical field load, and extracting a thermal-mechanical response; homogenizing the microscopic model into material performance and transmitting the material performance to the microscopic model; constructing a woven composite material model through structural parameters on a microscale, and endowing the performance of the homogenized fiber bundles and the homogenized porous matrix; the periodic boundary condition of the service condition of the macrostructure and the multi-physical field load are applied to the mesoscopic model to obtain the thermal-mechanical response and performance degradation condition of the mesoscopic model and the fatigue damage condition under the cyclic load, and progressive failure analysis is completed; the actual response of the macrostructure in the multi-physical field is obtained; low-cost and high-precision numerical simulation and performance prediction of multiple scales and multiple physical fields are realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of composite materials, and in particular relates to a model building and simulation method, device and storage medium for a braided composite material. Background Art

[0002] In the prior art, since woven composite materials are made of fiber bundles woven along the warp and weft directions and have complex microstructures, the test cost under multi-physical field loads represented by thermal cycles is high, and microscopic damage and thermo-mechanical responses are difficult to observe. Based on numerical methods and material constitutive law, a micro-meso-macro multi-scale model is constructed that considers the distribution of pores in the matrix, the weaving method, the phase properties of the material, and the changes in the material constitutive law and microstructure under thermal cycle loads, which can be used to guide structural design and reduce test costs.

[0003] A new modeling and simulation method for braided composites is needed. Summary of the invention

[0004] The purpose of the present invention is to provide a model construction and simulation method for a braided composite material, so as to solve the technical problems of high experimental cost and low measurement accuracy in the prior art.

[0005] The present invention also aims to provide a device for realizing a model building and simulation method of a braided composite material.

[0006] Another object of the present invention is to provide a computer-readable storage medium.

[0007] The technical solution of the present invention to solve the technical problem is: A model building and simulation method for a braided composite material comprises the following steps: S1: On the microscopic scale of the woven composite material, a fiber bundle model including fibers, matrix, pores, and interfaces and a porous matrix model including pores and matrix are established respectively. Material properties are assigned to the fiber bundle model and the porous matrix model according to the existing material library data or the observation data during the test process. According to the observation results, the structural parameters of the microscopic scale are assigned to complete the construction of the multi-scale model. S2: By applying multi-physics field loads transmitted from the microscopic model to the fiber bundle model and porous matrix model after the material properties are given and extracting the response, the material performance degradation conditions related to the elastic-plastic constitutive structure, high-temperature thermal properties, and fracture energy are obtained; the performance of the microscopic model is equivalent to a thermo-mechanical response curve, which is homogenized and then transmitted to the homogenized fiber bundle and homogenized porous matrix in the microscopic woven composite material model; S3: Assign properties to homogenized fiber bundles and homogenized porous matrices at the microscopic scale of woven composite materials; convert the service conditions of the macroscopic structure into loads and boundary conditions and apply them to the microscopic model, calculate the multi-physical field response as the load and transfer it to the microscopic model; after updating the thermo-mechanical response, obtain the performance degradation of the mesoscopic model and the fatigue damage under cyclic load, complete the progressive failure analysis, and obtain the actual response of the macroscopic structure under multi-physical fields.

[0008] Furthermore, the structural parameters in step S1 include the diameter, aspect ratio, volume fraction, distribution pattern of the fibers and the median pore size, shape, distribution pattern, porosity of the pores at a microscopic scale, as well as the weaving density / bundle / cm, linear density / tex, and weaving pattern of the warp and weft yarns at a microscopic scale; the material properties include the mechanical and thermal properties of the initial matrix phase, interface phase, and fiber phase.

[0009] Furthermore, the multi-physical field load in step S2 includes stress-strain field load, heat flow load, and temperature load.

[0010] Furthermore, the high-temperature thermal properties in step S2 include thermal expansion coefficient, thermal conductivity, specific heat capacity, and thermal diffusivity at different temperatures.

[0011] Furthermore, the progressive failure analysis in step S3 includes three parts: stress analysis, failure analysis, and material degradation.

[0012] Furthermore, the step S3 of imparting properties to the homogenized fiber bundles and the homogenized porous matrix on a microscopic scale of the woven composite material specifically comprises the following steps: Q1: According to the ABAQUS solver, the strain field of the braided composite material is obtained through the finite element model, and the initial stress field of the braided composite material is calculated according to the stiffness matrix constructed by the grid nodes; Q2: The initial stress fields of the warp / weft yarns and the equivalent matrix calculated by the microscopic model are respectively entered into step Q3 according to the homogenized fiber bundles and into step Q4 according to the homogenized porous matrix, for failure judgment and stress update; Q3: Calculate the weighted average sum based on the ratio of stress to strength in the main direction of the material to determine whether the damage variable is greater than 1. If so, execute step Q3.1; if not, execute step Q5; Q3.1: Degrade the stiffness of the homogenized fiber bundle along the linear decline curve according to the strain value, and determine whether the stiffness value after degradation is zero through the fracture energy data. If so, perform integration point failure and mesh deletion operations and execute step Q5; if not, execute step Q5; Q4: Determine whether the stress value in the main direction of the material is higher than the strength value. If so, execute step Q4.1; if not, execute step Q5; Q4.1: Calculate the amplitude of ductile deformation of the homogenized porous matrix through the material constitutive model of ductile fracture, and determine whether the amplitude is lower than the fracture threshold. If so, execute step Q5; if not, fracture the homogenized porous matrix, perform integration point failure and mesh deletion operations, and execute step Q5; Q5: Update the stress field, strain field and overall stiffness matrix of braided composite materials.

[0013] A device for implementing a model building and simulation method for a braided composite material, comprising: The microstructure processing module is used to establish a fiber bundle model including fibers, matrix, pores, and interfaces, and a porous matrix model including pores and matrix, and assign structural parameters and material properties to the fiber bundle model and the porous matrix model according to the existing material library data or the observed data during the test process; by applying cyclic temperature field and multi-physical field loads to the assigned fiber bundle model and the porous matrix model and extracting the response, the material performance degradation of the elastic-plastic constitutive structure, high-temperature thermal properties, and fracture energy after thermal cycling is obtained; the fiber bundle model and the porous matrix model are homogenized into the material properties and transferred to the microscopic model; The mesostructure processing module is used to assign properties to homogenized fiber bundles and homogenized porous matrices; the periodic boundary conditions and multi-physical field loads of the macrostructure service conditions are applied to the mesomodel to obtain the thermo-mechanical response and performance degradation of the mesomodel, as well as the fatigue damage under cyclic loads, to complete the progressive failure analysis; and the actual response of the macrostructure under multi-physical fields is obtained.

[0014] The judgment module is used to judge whether the damage variable is greater than 1; whether the stiffness value after degradation is zero; whether the stress value in the main direction of the material is higher than the strength value; and whether the amplitude of ductile deformation is lower than the fracture threshold.

[0015] A computer-readable storage medium stores a computer program, wherein when the computer program is executed by a processor, the device where the computer-readable storage medium is located executes a model building and simulation method for a woven composite material.

[0016] The beneficial effects of the present invention are: By assigning material properties to the fiber bundle model and porous matrix model at the microscopic scale, and then applying multi-physics field loads and extracting the thermo-mechanical response; homogenizing the microscopic model into material properties and transferring them to the mesoscopic model; constructing a woven composite material model through structural parameters at the mesoscopic scale, and assigning properties to the homogenized fiber bundle and the homogenized porous matrix; applying the periodic boundary conditions and multi-physics field loads of the macroscopic structure service conditions to the mesoscopic model to obtain the thermo-mechanical response and performance degradation of the mesoscopic model, and the fatigue damage under cyclic loads, and complete the progressive failure analysis; and obtaining the actual response of the macroscopic structure under multi-physics fields. Low-cost, high-precision multi-scale and multi-physics field numerical simulation and performance prediction are achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A flow chart of the model building and simulation method of the present invention; Figure 2 This is the flow chart of the UMAT subroutine when used for progressive failure analysis; Figure 3 The invention relates to the construction of a micro-meso-macro multi-scale model of the woven composite material involved in the present invention; Figure 4 Material phase distribution and mesh division of the multi-scale model: (a) micro-porous matrix; (b) micro-fiber bundle; (c)-(d) micro-woven composite material; Figure 5 Simulation analysis of thermal cycle fatigue damage process of braided composite materials; Figure 6 A research proposal for the use of multi-scale models for thermal cycling performance degradation simulation. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0019] Embodiment 1: like Figure 1 As shown, the present invention discloses a model construction and simulation method of a braided composite material, comprising the following steps: S1: On the microscopic scale of the woven composite material, a fiber bundle model including fibers, matrix, pores, and interfaces and a porous matrix model including pores and matrix are established respectively. Material properties are assigned to the fiber bundle model and the porous matrix model according to the existing material library data or the observation data during the test process. According to the observation results, the structural parameters of the microscopic scale are assigned to complete the construction of the multi-scale model. Among them, the structural parameters include the diameter, aspect ratio, volume fraction, distribution mode of the fibers and the median pore size, shape, distribution mode, porosity of the pores at the microscopic scale, as well as the weaving density / bundle / cm, linear density / tex, and weaving mode of the warp and weft yarns at the microscopic scale; the material properties include the mechanical and thermal properties of the initial matrix phase, interface phase, and fiber phase.

[0020] S2: Apply multi-physics field loads transmitted from the microscopic model to the fiber bundle model and porous matrix model after the material properties are given, and extract the response; the multi-physics field loads include stress-strain field loads, heat flow loads, and temperature loads. For example, if a uniaxial / multiaxial tensile load is applied, a stress-strain curve can be obtained, which is characterized as an elastic-plastic constitutive model. If a heat flow load is applied, a temperature field-time relationship can be obtained, which is characterized as a thermal physical property; if a temperature load is applied, a strain field-temperature relationship can be obtained, which is characterized as a thermal expansion coefficient; the elastic-plastic constitutive model describes the deformation of the material when it is subjected to force, and this deformation includes two parts: elastic deformation and plastic deformation. For example, in the ductile fracture model used in strength analysis, the stress-strain curve is divided into elastic, yield, stiffness degradation, and fracture stages; in the dynamic bilinear hardening constitutive model used in thermal cycle fatigue analysis, its elastic modulus, yield strength, and tangent modulus are all related to temperature and the number of cycles. The thermal properties used in heat transfer analysis include thermal conductivity, thermal diffusivity, specific heat capacity, etc., and are related to temperature. The degradation of material properties related to elastic-plastic constitutive structure, high-temperature thermal properties, and fracture energy after thermal cycling is obtained, and the high-temperature thermal properties include thermal expansion coefficient, thermal conductivity, specific heat capacity, and thermal diffusivity at different temperatures. The performance of the microscopic model is equivalent to a curve of thermo-mechanical response, and after homogenization, it is transferred to the fiber bundles with homogenized warp / weft yarns and the porous matrix with homogenized equivalent matrix in the microscopic woven composite material model.

[0021] S3: Assign properties to homogenized fiber bundles and homogenized porous matrices at the microscopic scale of woven composite materials; convert the service conditions of the macroscopic structure into loads and boundary conditions and apply them to the microscopic model, calculate the multi-physical field response as the load and transfer it to the microscopic model; after updating the thermo-mechanical response, obtain the performance degradation of the mesoscopic model and the fatigue damage under cyclic load, complete the progressive failure analysis, and obtain the actual response of the macroscopic structure under multi-physical fields.

[0022] Among them, the service conditions of macro structures include: stress fields generated by displacement loads, such as multi-axial tension, compression, and shear loads; temperature fields and thermal stress fields generated by heat transfer, as well as the convection / conduction / radiation methods used; time-related alternating loads, such as thermal cycles caused by alternating heating and displacement cycles caused by repeated loading; physical fields caused by extreme working conditions, such as ablation oxidation and surface ionization.

[0023] Progressive failure analysis includes three parts: stress analysis, failure analysis, and material degradation. The stress-strain field can be obtained by applying loads and boundary condition analysis in the finite element model. Failure analysis is responsible for detecting whether the grid integration point fails and determining the failure mode. Material degradation is used to describe the stiffness degradation process after the integration point fails.

[0024] Typical forms of failure include: matrix fragmentation and matrix peeling at the mesoscopic scale, fiber bundle breakage, and fiber bridging, fiber pullout, matrix cracking, and interface debonding at the microscopic scale.

[0025] like Figure 2 As shown, the step S3 imparts properties to the homogenized fiber bundles and the homogenized porous matrix on a microscopic scale of the woven composite material, specifically comprising the following steps: Q1: According to the ABAQUS solver, the strain field of the braided composite material is obtained through the finite element model, and the initial stress field of the braided composite material is calculated according to the stiffness matrix constructed by the grid nodes; Q2: The initial stress fields of the warp / weft yarns and the equivalent matrix calculated by the microscopic model are respectively entered into step Q3 according to the homogenized fiber bundles and into step Q4 according to the homogenized porous matrix, for failure judgment and stress update; Q3: Calculate the weighted average sum based on the ratio of stress to strength in the main direction of the material to determine whether the damage variable is greater than 1. If so, execute step Q3.1; if not, execute step Q5; Q3.1: Degrade the stiffness of the homogenized fiber bundle along the linear decline curve according to the strain value, and determine whether the stiffness value after degradation is zero through the fracture energy data. If so, perform integration point failure and mesh deletion operations and execute step Q5; if not, execute step Q5; Q4: Determine whether the stress value in the main direction of the material is higher than the strength value. If so, execute step Q4.1; if not, execute step Q5; Q4.1: Calculate the amplitude of ductile deformation of the homogenized porous matrix through the material constitutive model of ductile fracture, and determine whether the amplitude is lower than the fracture threshold. If so, execute step Q5; if not, fracture the homogenized porous matrix, perform integration point failure and mesh deletion operations, and execute step Q5; Q5: Update the stress field, strain field and overall stiffness matrix of braided composite materials.

[0026] Taking a woven composite material with a warp density of 8 yarns / cm, a weft density of 2.5 yarns / cm, a fiber density of 205tex in the warp and weft yarns, and a volume fraction of 43% as an example, the specific model construction and simulation methods are as follows: S1: Establish a multi-scale model based on experimental observations. It is observed that the warp density of the woven composite material is 8 yarns / cm and the weft density is 2.5 yarns / cm, where the fiber density in the warp and weft yarns is 205 tex and the volume fraction is 43%. Figure 3 -a, the smallest microelement is selected to establish a microscopic model, and its size is 16×5×3.8mm. The warp and weft yarns and the matrix are observed using a scanning electron microscope, and the diameter of the fiber in the fiber bundle is measured to be 10 μm, and the fiber volume fraction Vf=73.23%; the porosity (density method) in the porous matrix is ​​52.7%, and the median pore size (mercury intrusion method) is 0.6 μm. Figure 3 -b, a microscopic fiber bundle model with a side length of 50 μm was established, as shown in Figure 3 -c, a microscopic porous matrix model with a side length of 1 μm was established.

[0027] The model is meshed and boundary conditions are applied. The models in this embodiment are all constructed using Digmat software and solved using ABAQUS / Standard. The meshing of the multi-scale model is as follows: Figure 4 As shown, the mesh types of each phase of the material are four-node linear tetrahedron elements (C3D4). The surface / surface action defined by general contact has a tangential friction coefficient of 0.5. Since the microelement is selected from the macrostructure, it is necessary to ensure that the deformation of the model is coordinated when loaded. Therefore, periodic boundary conditions (PBC) are applied to each external surface of the model, that is, coupling constraints are applied to the nodes of the relative surface, so that each node has equal displacement when loaded.

[0028] S2: Analysis of fatigue damage process of thermal cycle. First, set the initial temperature of micro and meso models to 0℃ (room temperature is also acceptable), then raise the temperature field to a constant value (400℃), then lower it to the initial temperature, and end the analysis after the sinusoidal curve cycles for a specified number of times (100 times). Figure 5 -a, at the microscopic level: due to the huge difference in thermal expansion coefficients between the fiber and the matrix and the high modulus of the fiber, the matrix will produce alternating thermal stress, and after multiple thermal cycles, multiple fracture zones will be generated longitudinally and the structure will tend to be stable. Figure 5 As shown in Figure 2-b, as the number of warm-heat cycles increases, the stress on some interfaces accumulates and exceeds the strength, resulting in interface debonding. Figure 5 As shown in Figure 1-c, the pores are randomly distributed in the matrix, resulting in uneven conduction of thermal stress in the matrix, and stress concentration occurs at the pore agglomeration points; therefore, matrix cracking occurs first at the pore agglomeration points, and continues with the thermal cycle until complete failure. Analysis at the microscopic level: Due to the large difference in the transverse and longitudinal thermal expansion coefficients of the fiber bundle, there is severe stress concentration at the intersection interface of the warp yarn (x-direction carbon fiber bundle) and the weft yarn (y-direction carbon fiber bundle). Figure 5As shown in Figure 2-d, as the number of cycles increases, the plastic zone is generated from the intersection interface and grows along the thickness direction, and finally certain microcracks are generated.

[0029] like Figure 6 As shown in the simulation of performance degradation after thermal cycling, even if the fiber performance is stable at high temperature, matrix cracking and interface debonding will cause the fiber bundle performance to degrade as the temperature rises. The microscopic model after thermal cycling can be subjected to uniaxial stretching, and the stress-strain curve can be transferred to the microscopic scale as the mechanical property. During the uniaxial stretching process, the stretching surface is coupled with the reference point RP, and the displacement constraint is given at RP. The curve of the model is output through the reference point, and the displacement load is applied to the model at a uniform speed until the set value is reached, and the stress-strain curve is drawn synchronously. By converting the stress-strain curves of the microscopic fiber bundles and porous matrix, as well as the strength values, thermal expansion coefficients and yield points at the corresponding temperatures, the equivalent homogenization and performance transfer of the microscopic warp and weft yarns and equivalent matrix are completed.

[0030] For the microscopic model of performance degradation after thermal cycling, finite elements can be used to apply uniaxial or multiaxial tension along the longitudinal (x-axis) and latitudinal (y-axis) directions for progressive failure analysis, or multi-physics load response analysis can be performed according to the service conditions.

[0031] S3: Multi-level homogenization and performance transfer. In the constructed multi-scale model, the performance of the microscopic fiber bundle is transferred to the microscopic warp and weft yarns, and the performance of the microscopic porous matrix is ​​transferred to the microscopic equivalent matrix. After homogenization and equivalence, the microscopic model is regarded as the same homogeneous material phase in the microscopic model. The transferred properties include: thermophysical properties, such as thermal conductivity, specific heat capacity, thermal expansion coefficient, etc.; mechanical properties, such as elastic modulus, yield stress, plastic strain, strength, elongation at break, etc.; others, such as density, creep, viscosity, damping, etc.; when it comes to heat transfer analysis and temperature field, the material properties are related to temperature. The properties are generally extracted from the finite element analysis curve of the microscopic model, and the corresponding material constitutive model is selected for characterization and fitting. In the progressive failure analysis, Python software is used to write the UMAT subroutine (User-Material) for ABAQUS, and the porous matrix is ​​characterized by the ductile fracture model and the fiber bundle is characterized by the Hashin damage criterion.

[0032] Multi-physics field load application. Select the required analysis method according to the structural service conditions and apply the load. The following are relevant examples.

[0033] Working condition 1, heat transfer-thermal property analysis: There are two types of heat transfer analysis used in this example: steady state and transient. In the macroscopic structure and microscopic model, the heat flux applied on the surface is conducted along the thickness until it reaches the bottom surface and produces a transient temperature rise; while the microscopic model is a unit cell, the time consumption of heat flux conduction can be ignored, and a stable temperature gradient is generated at any time. In order to meet the periodic boundary conditions, adiabatic boundaries are used on both sides of the model. A steady-state heat transfer analysis is performed on the microscopic fiber bundle and porous matrix model, and the thermal properties in the orthogonal directions are assigned to each phase of the mesoscopic model; a transient heat transfer analysis is performed on the mesoscopic model of the woven composite material to characterize the temperature field and thermal stress field of the macroscopic structure under service conditions after thermal cycling.

[0034] Working condition 2, multiaxial load-progressive failure analysis: establish a reference point on the microscopic model (including fiber bundles and porous matrix) and couple it with the loading surface, apply transverse / longitudinal tension and shear loads to the reference point respectively, and obtain stress-strain curves and corresponding failure modes. Due to the large difference in the transverse and longitudinal properties of the fiber bundle, it is necessary to perform failure analysis under combined stress to describe the progressive failure form of the macrostructure in a complex stress field. Couple the fiber bundle according to different loading paths (radial, orthogonal, tortuous), such as radially applying multiaxial loads at a fixed combined strain ratio until it fails, and then output the mechanical response under different loading ratios and draw the failure envelope surface, and transfer the mechanical properties to the warp and weft yarns through the UMAT subroutine. Apply multiaxial loads to the microscopic woven composite model, and use the subroutine to judge and correct the stiffness matrix, stress and damage state of the grid integration point to complete the progressive failure analysis.

[0035] Analysis and design optimization of thermomechanical response under macrostructure service conditions. The results show that matrix cracking and interface debonding after thermal cycling lead to performance degradation and affect the stress field and temperature field of the macrostructure. Due to the difference in thermal expansion coefficients between the fiber and the matrix, the temperature change caused by the thermal cycle causes huge thermal stress at the interface. When the thermal stress at the pores exceeds the yield strength, the matrix produces plastic strain and has the following effects on the microstructure: 1. The dislocation substructure changes, accompanied by cyclic hardening or softening; 2. Microcracks occur in the matrix or develop into micropores; 3. Debonding and slippage occur at the interface. The corresponding working condition results are as follows: Working condition 1: The results show that the multi-scale model can explain the linear stage, nonlinear stage and quasi-linear stage of the stress-strain curve of the braided composite material under multiaxial tension, as well as the corresponding damage evolution process. The fracture morphology of the braided composite material includes: matrix fragment desquamation and matrix peeling at the mesoscale, and fiber breakage, fiber pull-out, matrix cracking, interface debonding at the microscale. The present invention can reveal the damage evolution process of the material under thermal cycling, the relationship between macroscopic load and microscopic failure, and the multiaxial load coupling failure mechanism.

[0036] Condition 2: The results show that the structural form has an important influence on the thermal properties and temperature field. Fibers are the main heat transfer channels, and the heat flow is mainly conducted along the channels formed by fibers or overlaps; pores and manufacturing defects produce thermal resistance, hindering the conduction of heat flow. By adjusting the fiber / pore distribution and the two-dimensional / three-dimensional weaving method, designing heat transfer channels and constructing an effective heat transport network, the anti-heat / insulation properties of composite materials can be redesigned.

[0037] Embodiment 2: A device for implementing a model building and simulation method for a braided composite material, comprising: The microstructure processing module is used to establish a fiber bundle model including fibers, matrix, pores, and interfaces, and a porous matrix model including pores and matrix, and assign structural parameters and material properties to the fiber bundle model and the porous matrix model according to the existing material library data or the observed data during the test process; by applying cyclic temperature field and multi-physical field loads to the assigned fiber bundle model and the porous matrix model and extracting the response, the material performance degradation of the elastic-plastic constitutive structure, high-temperature thermal properties, and fracture energy after thermal cycling is obtained; the fiber bundle model and the porous matrix model are homogenized into the material properties and transferred to the microscopic model; The mesostructure processing module is used to assign properties to homogenized fiber bundles and homogenized porous matrices; the periodic boundary conditions and multi-physical field loads of the macrostructure service conditions are applied to the mesomodel to obtain the thermo-mechanical response and performance degradation of the mesomodel, as well as the fatigue damage under cyclic loads, to complete the progressive failure analysis; and the actual response of the macrostructure under multi-physical fields is obtained.

[0038] The judgment module is used to judge whether the damage variable is greater than 1; whether the stiffness value after degradation is zero; whether the stress value in the main direction of the material is higher than the strength value; and whether the amplitude of ductile deformation is lower than the fracture threshold.

[0039] Embodiment 3: A computer-readable storage medium stores a computer program, wherein when the computer program is executed by a processor, the device where the computer-readable storage medium is located executes a model building and simulation method for a woven composite material.

[0040] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making any creative work shall fall within the scope of protection of the present invention.

Claims

1. A model construction and simulation method for braided composite materials, characterized in that , including the following steps: S1: On the microscopic scale of the woven composite material, a fiber bundle model including fibers, matrix, pores, and interfaces and a porous matrix model including pores and matrix are established respectively. Material properties are assigned to the fiber bundle model and the porous matrix model according to the existing material library data or the observation data during the test process. According to the observation results, the structural parameters of the microscopic scale are assigned to complete the construction of the multi-scale model. S2: By applying multi-physics field loads transmitted from the microscopic model to the fiber bundle model and porous matrix model after the material properties are given and extracting the response, the material performance degradation conditions related to the elastic-plastic constitutive structure, high-temperature thermal properties, and fracture energy are obtained; the performance of the microscopic model is equivalent to a thermo-mechanical response curve, which is homogenized and then transmitted to the homogenized fiber bundle and homogenized porous matrix in the microscopic woven composite material model; S3: Assign properties to homogenized fiber bundles and homogenized porous matrices at the microscopic scale of woven composites; convert the service conditions of the macroscopic structure into loads and boundary conditions and apply them to the microscopic model, calculate the multi-physics field response as load and transfer it to the microscopic model; After the thermo-mechanical response is updated, the performance degradation of the micro-model and the fatigue damage under cyclic load are obtained, and the progressive failure analysis is completed; the actual response of the macro-structure under multi-physical fields is obtained.

2. The model building and simulation method of the braided composite material according to claim 1, characterized in that: The structural parameters in step S1 include the diameter, aspect ratio, volume fraction, distribution mode of the fibers and the median pore size, shape, distribution mode, porosity of the pores at a microscopic scale, as well as the weaving density / bundle / cm, linear density / tex, and weaving mode of the warp and weft yarns at a microscopic scale; the material properties include the mechanical and thermal properties of the initial matrix phase, interface phase, and fiber phase.

3. The model building and simulation method of the braided composite material according to claim 1, characterized in that: The multi-physical field load in step S2 includes stress-strain field load, heat flow load, and temperature load.

4. The model building and simulation method of the braided composite material according to claim 1, characterized in that: The high-temperature thermal properties in step S2 include thermal expansion coefficient, thermal conductivity, specific heat capacity, and thermal diffusivity at different temperatures.

5. The model building and simulation method of the braided composite material according to claim 1, characterized in that: The progressive failure analysis in step S3 includes three parts: stress analysis, failure analysis, and material degradation.

6. The model building and simulation method of the braided composite material according to claim 1, characterized in that: In step S3, the properties of the homogenized fiber bundles and the homogenized porous matrix are imparted on a microscopic scale to the woven composite material, specifically comprising the following steps: Q1: According to the ABAQUS solver, the strain field of the braided composite material is obtained through the finite element model, and the initial stress field of the braided composite material is calculated according to the stiffness matrix constructed by the grid nodes; Q2: The initial stress fields of the warp / weft yarns and the equivalent matrix calculated by the microscopic model are respectively entered into step Q3 according to the homogenized fiber bundles and into step Q4 according to the homogenized porous matrix, for failure judgment and stress update; Q3: Calculate the weighted average sum based on the ratio of stress to strength in the main direction of the material to determine whether the damage variable is greater than 1. If so, execute step Q3.1; if not, execute step Q5; Q3.1: Degrade the stiffness of the homogenized fiber bundle along the linear decline curve according to the strain value, and determine whether the stiffness value after degradation is zero through the fracture energy data. If so, perform integration point failure and mesh deletion operations and execute step Q5; if not, execute step Q5; Q4: Determine whether the stress value in the main direction of the material is higher than the strength value. If so, execute step Q4.1; if not, execute step Q5; Q4.1: Calculate the amplitude of ductile deformation of the homogenized porous matrix through the material constitutive model of ductile fracture, and determine whether the amplitude is lower than the fracture threshold. If so, execute step Q5; if not, fracture the homogenized porous matrix, perform integration point failure and mesh deletion operations, and execute step Q5; Q5: Update the stress field, strain field and overall stiffness matrix of braided composite materials.

7. A device for implementing the model building and simulation method of a braided composite material according to any one of claims 1 to 6, characterized in that: include: The microstructure processing module is used to establish a fiber bundle model including fibers, matrix, pores, and interfaces, and a porous matrix model including pores and matrix, and assign structural parameters and material properties to the fiber bundle model and the porous matrix model according to the existing material library data or the observation data during the test process; by applying cyclic temperature field and multi-physical field loads to the assigned fiber bundle model and the porous matrix model and extracting the response, the material performance degradation of the elastic-plastic constitutive structure, high-temperature thermal properties, and fracture energy after thermal cycling is obtained; the fiber bundle model and the porous matrix model are homogenized into the material properties and transferred to the microscopic model; The microstructure processing module is used to assign properties to homogenized fiber bundles and homogenized porous matrices; the periodic boundary conditions and multi-physics field loads of the macrostructure service conditions are applied to the micromodel to obtain the thermo-mechanical response and performance degradation of the micromodel, the fatigue damage under cyclic loads, and complete the progressive failure analysis; the actual response of the macrostructure under multi-physics fields is obtained; The judgment module is used to judge whether the damage variable is greater than 1; whether the stiffness value after degradation is zero; whether the stress value in the main direction of the material is higher than the strength value; and whether the amplitude of ductile deformation is lower than the fracture threshold.

8. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the device where the computer-readable storage medium is located executes the method according to any one of claims 1 to 6.

Images