Method for predicting material properties of a fiber-interleaved, wrapped shell closure head structure

Abstract

The present application relates to a kind of considering the performance prediction method of winding shell head structure material of fiber staggered overhead, the resin volume fraction formed by deducing, calculating the fiber yarn staggered overhead of head area is combined with the material performance calculation method of composite mechanics homogenization material, the material performance variation law of winding shell head structure along axial direction is accurately predicted, and the precision of finite element simulation calculation result of shell head structure can be improved by realizing material attribute accurate matching in combination with finite element simulation software.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of structural material performance prediction methods, and relates to a structural material performance prediction method for a winding shell head structure considering fiber stagger and airframe. BACKGROUND

[0002] The solid rocket engine shell plays a crucial role in the entire engine system. As the main load-bearing structure, it has a key influence on the overall performance and safety of the rocket. During the rocket's launch, flight, and final mission completion, the engine shell must withstand extreme pressure, temperature, and complex mechanical environments. Its quality and performance are directly related to the success of the rocket mission. The emergence of fiber-wound composite material shells has revolutionized numerous fields. This advanced material has a series of remarkable advantages. Its lightweight nature allows the equipment it is mounted on to effectively reduce its own weight, resulting in significant improvements in energy consumption and flight efficiency. Its high strength ensures structural integrity under heavy pressure and complex stress, preventing easy breakage or deformation. Moreover, it has excellent corrosion resistance, allowing it to work stably in harsh atmospheric environments, chemical corrosion environments, and other complex working conditions. Most notably, this material is highly designable, allowing researchers to precisely adjust fiber direction, winding angle, and layer number based on specific usage requirements and working environments to customize structures that best meet the needs.

[0003] Currently, the main method for predicting the material performance of winding shells in actual engineering is the laminate theory. The winding composite material structure is simplified as a laminate structure, and it is assumed that the fiber volume fraction at each position is the same. Then, based on the stress-strain relationship of each single-layer plate and the laminate theory, the stiffness matrix of each single-layer plate is integrated into the total stiffness matrix of the winding structure. However, during the fiber winding process, fiber stagger and airframe may occur. The prediction based solely on the laminate theory has a large error compared to the actual situation. To achieve high-precision prediction of the stress field of the composite material shell head, the meso-structure characteristics of the shell head section need to be considered, and the method for predicting the material performance of the winding shell based on the laminate theory needs to be modified.

[0004] Therefore, the present application proposes a winding shell head structure material performance prediction method considering fiber stagger and airframe. It specifically addresses the problems of fiber stagger and airframe in fiber-wound composite material shell head structures, considers the influence of the meso-structure characteristics of the winding shell head caused by the winding process on the material performance, and improves the precision of the simulation analysis of the composite material shell head structure. SUMMARY

[0005] The technical problem to be solved

[0006] To address the shortcomings of existing technologies, this invention proposes a method for predicting the material properties of wound shell end cap structures that consider interwoven fiber support. This method aims to solve the problem that existing analytical methods do not adequately consider the influence of the microstructure of the shell end cap, resulting in large errors in the prediction of material properties at the end cap and distortion in the failure analysis of the shell end cap. The specific technical solution of this invention is as follows:

[0007] Technical solution

[0008] A method for predicting the material properties of a wound shell end cap structure considering interwoven and suspended fibers, characterized by the following steps:

[0009] Step 1: Discretize the shell head structure according to the shell axis to obtain several latitude circles of each section parallel to the head, and the radius r of each latitude circle;

[0010] Step 2: Calculate the overlap rate v between adjacent fiber yarns at each latitude circle. r To characterize the degree to which the fiber bundles and yarns of the wound shell end cap structure are interlaced and suspended;

[0011] Step 3: Based on the overlap rate of the fiber yarns of the wound shell end cap structure, calculate the resin volume fraction η on each latitude circle of the end cap structure. r ;

[0012]

[0013] The S 总纤维纱 =nbh

[0014] Wherein: S 总架空 Let h be the total cross-sectional area of ​​the fiber yarn at any parallel circle of the winding shell head structure and the total cross-sectional area of ​​the triangular overhead area, where h is the fiber yarn thickness, n is the total number of fiber yarns passing through any parallel circle of the shell cylinder section, and b is the fiber yarn width.

[0015] Cross-sectional area of ​​the elevated triangular region at any parallel circle of the head structure

[0016] Step 4: Calculate the resin volume fraction η on several latitude circles. r The variation law of the volume fraction of the suspended area constituting the wound shell head structure expresses that the suspended area is eventually filled with resin to form a resin-rich area.

[0017] Step 5: Based on the obtained resin volume fraction variation law, calculate the equivalent material performance parameters of the wound shell end cap structure using the composite material mechanical homogenization method, including: the equivalent elastic modulus E1 of the end cap material parallel to the fiber direction, the equivalent elastic modulus E2 of the end cap material perpendicular to the fiber direction, and the equivalent in-plane shear modulus G of the end cap material. 12 The equivalent out-of-plane shear modulus G of the head material23 , the in-plane equivalent Poisson's ratio of the head material v 12 , the out-of-plane equivalent Poisson's ratio of the head material v 23 ;

[0018] Step 6: The material performance parameters at different parallel circle radii of the head are input into the Abaqus finite element simulation software. In the Abaqus finite element simulation software, the material parameters at the corresponding parallel circles are assigned to the positions of the corresponding geometric partitions, to obtain the characterization of the predicted results of the material of the winding shell head structure.

[0019] The overlap rate between adjacent fiber yarns at each latitude circle Wherein: b v is the width of the effective projection of a single fiber yarn of the winding shell head structure at any parallel circle, i.e. the non-interlaced and overlapped area, b r is the projection width of a single fiber yarn of the winding shell head at any parallel circle.

[0020] The overlap rate between adjacent fiber yarns at each latitude circle Wherein: r is the radius of any parallel circle of the shell head, R is the radius of the shell body section, a is the fiber yarn winding angle at the corresponding parallel circle of the head, a0 is the winding angle of the fiber yarn of the body section.

[0021] The projection width of a single fiber yarn of the winding shell head at any parallel circle Wherein, r is the radius of any parallel circle of the shell head, a is the winding angle at the corresponding parallel circle of the head.

[0022] The width of the effective projection of a single fiber yarn of the winding shell head structure at any parallel circle, i.e. the non-interlaced and overlapped area Wherein: b is the width of the fiber yarn, a0 is the winding angle of the fiber yarn of the body section, r is the radius of any parallel circle of the shell head, R is the radius of the shell body section.

[0023] The h is the thickness of the fiber yarn, β is the included angle of the fiber yarn and the parallel circle, γ is the area correction factor of the resin triangular area, n is the total number of fiber yarns passing through any parallel circle of the shell body section.

[0024] The total number of fiber yarns passing through any parallel circle of the shell body section:

[0025]

[0026] Wherein: R is the radius of the shell body section, a0 is the winding angle of the fiber yarn of the body section, b is the width of the fiber yarn.

[0027] The material performance parameters at different parallel circle radii of the head calculated in step 5 use the following formula:

[0028]

[0029] wherein E1 is the equivalent elastic modulus of the end fitting material in the direction parallel to the fiber, E2 is the equivalent elastic modulus of the end fitting material in the direction perpendicular to the fiber, E 1f is the elastic modulus of the carbon fiber in the direction of the fiber, E 2f is the elastic modulus of the carbon fiber in the direction perpendicular to the fiber, E m is the elastic modulus of the resin matrix; G 12 is the equivalent in-plane shear modulus of the end fitting material, G 23 is the equivalent out-of-plane shear modulus of the end fitting material, G 12f is the in-plane shear modulus of the carbon fiber, G 23f is the out-of-plane shear modulus of the carbon fiber, G m is the shear modulus of the resin matrix; v 12 is the in-plane equivalent Poisson's ratio of the end fitting material, v 23 is the out-of-plane equivalent Poisson's ratio of the end fitting material, v 12f is the in-plane Poisson's ratio of the carbon fiber, v 23f is the out-of-plane Poisson's ratio of the carbon fiber, v m is the Poisson's ratio of the resin matrix; c f is the fiber volume fraction, c m is the resin volume fraction; η2, η 12 , η 23 , a is an empirical parameter.

[0030] The calculation of the empirical parameters η2, η 12 , η 23 is as follows:

[0031]

[0032] A use of the method for predicting the performance of the end fitting structure material of the winding shell considering the fiber staggered overhead, characterized in that: the volume fraction of the overhead area caused by the winding process in the end fitting area of the shell is considered, and the equivalent material parameters are calculated, a finite element model of the winding shell considering the fiber staggered overhead is further established, an internal pressure load is applied to simulate the working condition of the winding shell under the internal pressure load, and the material performance prediction of the end fitting structure of the winding shell is realized.

[0033] Advantages

[0034] The present application is based on the fact that the existing analysis method does not consider the influence of the microstructure of the shell end fitting, which causes large material performance prediction error of the end fitting part and distorted failure analysis of the shell end fitting, and the present application proposes a method for predicting the material performance of the end fitting structure of the winding shell considering the fiber staggered overhead, and the specific steps are as follows:

[0035] Step one: define the fiber yarn overlap rate to represent the degree of fiber yarn staggered and overlapped in the winding shell head structure, and calculate the overlap rate between adjacent fiber yarns at any parallel circle radius of the winding shell head structure.

[0036] Step two: based on the fiber yarn overlap rate of the winding shell head structure, calculate the volume fraction of the overlapped area at different parallel circle radii of the head structure, that is, the volume fraction of the resin-rich area.

[0037] Step three: establish the change rule of the resin volume fraction of the winding shell head structure.

[0038] Step four: based on the homogenization method in composite mechanics, combined with the change rule of the resin volume fraction, calculate the equivalent material performance parameters of the winding shell head structure.

[0039] Step five: based on the ABAQUS finite element simulation software, realize the characterization of the material prediction results of the winding shell head structure. Compare the simulation results of the shell water pressure explosion of the two shell finite element models considering and not considering the material performance parameter change of the head structure due to the staggered and overlapped fiber.

[0040] The winding shell head structure material performance prediction method considering the fiber staggered and overlapped fiber proposed in the application defines the overlap rate of adjacent fiber yarns in the head, deduces and calculates the resin volume fraction formed by the staggered and overlapped fiber yarns in the head area, and combines the composite material mechanics homogenization material performance calculation method to accurately predict the material performance change rule of the winding shell head structure along the axial direction. Combined with the finite element simulation software, the material attribute can be accurately matched, which can improve the accuracy of the finite element simulation calculation results of the shell head structure. BRIEF DESCRIPTION OF DRAWINGS

[0041] Figure 1 The winding shell head fiber yarn stacking lap diagram.

[0042] Figure 2 The winding shell head fiber yarn overlap rate change diagram.

[0043] Figure 3 The winding shell body section development plan view.

[0044] Figure 4 The winding shell head fiber yarn overlap rate calculation diagram.

[0045] Figure 5 The fiber overlapped triangular area cross-sectional area calculation diagram.

[0046] Figure 6 The fiber yarn overlap rate and the winding shell head overlapped area volume fraction change diagram.

[0047] Figure 7 The solid winding shell finite element model diagram.

[0048] Figure 8 Shell head material attribute assignment diagram.

[0049] Figure 9 Shell simulation failure damage diagram considering resin-rich zone.

[0050] Figure 10 Shell simulation failure damage diagram not considering resin-rich zone. DETAILED DESCRIPTION

[0051] The present application will be further described in conjunction with the embodiments, drawings:

[0052] The technical solution of the present application is as follows, the intermediate transition parameters and functions designed in the following steps are examples, including but not limited to the following naming methods:

[0053] See Figures 1-4 The present embodiment defines the fiber yarn overlap rate to represent the degree of fiber bundle yarn overlap of the wound shell head structure, and calculates the overlap rate of the fiber yarn at any parallel circle radius of the wound shell head structure. The fiber yarn will continuously overlap on the surface of the shell head core mold, and the adjacent two fiber yarns will gradually completely overlap. In order to represent the degree of overlap between the fiber yarns, the fiber yarn overlap v needs to be defined, and the overlap rate of the fiber yarn at any parallel circle radius of the wound shell head structure is further calculated.

[0054] Figure 1 In the barrel section, the adjacent fiber yarns are arranged in parallel, that is, there is no stacking and no gap, and when the fiber yarn passes through the head area, the fiber yarn gradually overlaps together with the change of the curvature of the head.

[0055] Figure 2 In the figure, the area between the red lines represents fiber yarn 1, and the area between the adjacent black lines represents fiber yarn 2. The two fiber yarns are arranged in parallel at the equatorial circle, and gradually completely overlap together as the fiber yarns are wound towards the polar hole.

[0056] The specific steps are as follows:

[0057] Step one: discretely partition the shell head structure according to the shell axial direction, and extract the corresponding head parallel circle radius of each partition after discretization, which is used for subsequent calculation.

[0058] Step two: define the fiber yarn overlap rate to represent the degree of fiber bundle yarn overlap of the wound shell head structure.

[0059] Step three: calculate the overlap rate between adjacent fiber yarns at any parallel circle radius of the wound shell head structure.

[0060] The calculation method of the fiber yarn overlapping rate of the fiber winding shell head structure is as follows:

[0061] Step 1: Discretely partition the shell head structure according to the shell axial direction, and extract the head parallel circle radius corresponding to each partition after discretization.

[0062] Step 2: Calculate the projection width b of the single fiber yarn at any parallel circle of the winding shell body section t , see the shell body section plane expansion schematic diagram shown in Figure 3 , which can obtain:

[0063]

[0064] Wherein, b is the fiber yarn width, and a0 is the winding angle of the body section fiber yarn.

[0065] Step 3: Calculate the total number n of fiber yarns passing through the radius of any parallel circle of the shell body section when the fiber yarns are evenly distributed on the surface of the core mold for the first time under the spiral winding process:

[0066]

[0067] Wherein, R is the radius of the shell body section.

[0068] Step 4: Calculate the projection width b of the single fiber yarn at any parallel circle radius of the shell head without considering the fiber overlapping: r

[0069]

[0070] Wherein, r is the radius of any parallel circle of the shell head, and a is the winding angle at the corresponding parallel circle of the head.

[0071] Step 5: Calculate the projection width b of the single fiber yarn at any parallel circle radius of the winding shell head structure without overlapping area v

[0072] Since the fiber yarns are continuously wound on the surface of the shell core mold, it can be known that the total number of yarns passing through any parallel circle of the shell is consistent, that is, the total number of fiber yarns passing through any parallel circle of the head is consistent with the total number of fiber yarns passing through the parallel circle of the body section, both of which are n. According to this, the effective projection (non-interlaced and overlapping area) width of the single fiber yarn at any parallel circle of the winding shell head structure can be calculated:

[0073]

[0074] Step 6: Calculate the overlapping rate v between adjacent fiber yarns at any parallel circle radius of the winding shell head structure r

[0075] ​​​

[0076] Step four: Based on the overlap rate of the fiber yarn of the winding shell head structure, the volume fraction of the overhead area at different parallel circle radii of the head structure is calculated.

[0077] The specific steps of the resin volume fraction calculation method caused by the fiber interlaced overhead of the fiber winding shell head structure are as follows:

[0078] Step 1: Based on the calculated fiber yarn overlap rate of the shell head structure, the overhead area cross-sectional area S of any parallel circle radius of the head structure is derived and calculated 架空 :

[0079]

[0080] Wherein, L is the resin filling triangular area parameter, h is the fiber yarn thickness, β is the angle between the fiber yarn and the parallel circle, γ is the resin triangular area correction factor, which is related to the actual winding process parameter winding tension.

[0081] Step 2: Calculate the cross-sectional area S of a single fiber yarn at any parallel circle radius of the winding shell head structure 纤维纱 :

[0082] S 总纤维纱 = nbh

[0083]

[0084] Step 3: Through the ratio of the total cross-sectional area S of the overhead area at any parallel circle radius of the winding shell head structure 总架空 And the total cross-sectional area S of the fiber yarn 总纤维纱 , the volume fraction η of the overhead area at the corresponding parallel circle radius is obtained r :

[0085]

[0086] Step 4: Use MATLAB simulation software to discretize the shell head structure along the shell axial direction, calculate the volume fraction of the overhead area at all discrete parallel circle radii of the head structure, and draw the volume fraction change curve, see Figure 6 .

[0087] Step five: Based on the homogenization method of composite material mechanics, combined with the change rule of the resin volume fraction, the equivalent material performance parameters of the winding shell head structure are calculated. Abaqus finite element simulation software is used to realize the characterization of the prediction results of the winding shell head structure material.

[0088] Based on the material property homogenization calculation method in composite mechanics, combined with the resin volume fraction variation law of the winding shell head structure, the equivalent material property parameters at any parallel circle of the shell head are calculated. Combined with Abaqus finite element modeling simulation software, the precise matching of the material properties of the shell head structure is realized. The specific steps are as follows:

[0089] Step 1: According to the obtained volume fraction variation curve of the shell head overhead triangular area, the volume fraction variation curve of the resin-rich area of the shell head is obtained. In this method, it is considered that the overhead area is finally filled with resin to form a resin-rich area.

[0090] Step 2: According to the unidirectional fiber reinforced composite material performance homogenization calculation method in the composite mechanics analysis method, the material property parameters at different parallel circle radii of the head are calculated:

[0091]

[0092] Wherein, E1 is the equivalent elastic modulus of the head material in the direction parallel to the fiber, E2 is the equivalent elastic modulus of the head material in the direction perpendicular to the fiber, E 1f is the elastic modulus of carbon fiber in the fiber direction, E 2f is the elastic modulus of carbon fiber perpendicular to the fiber direction, E m is the elastic modulus of the resin matrix; G 12 is the equivalent in-plane shear modulus of the head material, G 23 is the equivalent out-of-plane shear modulus of the head material, G 12f is the in-plane shear modulus of carbon fiber, G 23f is the out-of-plane shear modulus of carbon fiber, G m is the shear modulus of the resin matrix; ν 12 is the in-plane equivalent Poisson's ratio of the head material, ν 23 is the out-of-plane equivalent Poisson's ratio of the head material, ν 12f is the in-plane Poisson's ratio of carbon fiber, ν 23f is the out-of-plane Poisson's ratio of carbon fiber, ν m is the Poisson's ratio of the resin matrix; c f is the fiber volume fraction, c m is the resin volume fraction; η2, η 12 , η 23 , a is an empirical parameter. As follows:

[0093]

[0094] Step 3: Based on the material performance homogenization calculation method of unidirectional fiber reinforced composites, combined with the resin content change curve, the equivalent material performance parameters corresponding to different parallel circles of the winding shell head structure are calculated, and the material performance is stored and output in the form of Python list. The output includes nine lists of E 11 = [], E 22 = [], E 33 = [], v 12 = [], v 13 = [], v 23 = [], G 12 = [], G 13 = [] and G 23 = [] corresponding to the nine material parameters in the Abaqus material engineering constant, and each list contains 54 material performance parameters corresponding to the 54 parallel circles discretized from the head structure area.

[0095] Step 4: Based on Abaqus finite element modeling simulation software, a shell geometry model is established, and the head is discretized into 54 partitions along the shell axis, as shown in Figure 7 .

[0096] Step 5: For each partition, read the variable according to its axial position, and give the material parameters corresponding to the position to accurately restore the head material distribution, as shown in Figure 8 .

[0097] Step 6: Compare the simulation results of shell water pressure explosion of two shell finite element models considering and not considering the change of material performance parameters of head structure due to fiber staggered overhead, as shown in Figure 9 、 Figure 10 . It is found that when considering the influence of head resin content, the shell failure occurs in the head section, and the failure position of the shell without considering the influence of resin content changes from the barrel section to the head.

[0098] Figure 9 、 Figure 10 , the material performance prediction method considering the fiber stacking overhead of the shell head structure makes the material performance characterization of the shell head area more accurate, and can more accurately predict the failure position of the head area.

Claims

1. A method for predicting the material properties of a wound shell end cap structure considering interlaced fiber suspension, characterized in that... The steps are as follows: Step 1: Discretely partition the shell head structure according to the shell axial direction to obtain a plurality of latitude circles parallel to the head of each partition and the radius of each partition latitude circle ; Step 2: Calculate the overlap ratio between adjacent fiber yarns at each latitude circle to characterize the degree of fiber bundle yarn strip interleaving and aerial spacing for the wrapped head structure. Step 3: Calculate the resin volume fraction on each latitude circle of the head structure based on the overlap ratio of the fiber yarns winding the head structure ; The The Wherein: Total area of fiber yarn cross section at any parallel circle of winding shell head structure Area of overhead triangular section at any parallel circle of head structure, Thickness of fiber yarn, Total number of fiber yarns passing through any parallel circle of shell barrel section, Width of fiber yarn; Step 4: resin volume fraction on several latitude circles The change rule of the volume fraction of the overhead area of the winding shell head structure is expressed, and it is finally expressed that the overhead area is filled by resin to form a resin-rich area; Step 5: According to the change rule of the volume fraction of the resin, the equivalent material performance parameters of the winding shell head structure are calculated by using the composite mechanics homogenization method, including: the equivalent elastic modulus of the head material in the direction parallel to the fiber , the equivalent elastic modulus of the head material in the direction perpendicular to the fiber , the equivalent in-plane shear modulus of the head material , the equivalent out-of-plane shear modulus of the head material , the equivalent in-plane Poisson's ratio of the head material , the equivalent out-of-plane Poisson's ratio of the head material ; Step 6: The material performance parameters at different parallel circle radii of the head are input into the Abaqus finite element simulation software, and in the Abaqus finite element simulation software, the material parameters at the corresponding parallel circles are assigned to the positions of the corresponding geometric partitions to obtain the characterization of the material prediction result of the winding shell head structure.

2. The method of claim 1, wherein the method further comprises: determining a material property of the winding shell closure structure based on the determined fiber layup. the overlap ratio between adjacent fiber yarns at each latitude circle wherein: Wp is the width of the effective projection of the single fiber yarn at any parallel circle, i.e. the area where there is no interleaving, overlapping, Wp is the width of the effective projection of the single fiber yarn at any parallel circle, i.e. the area where there is no interleaving, overlapping, 3. The method of claim 1, wherein the method further comprises: the overlap ratio between adjacent fiber yarns at each latitude circle wherein: Rsh is the shell head radius, Rsc is the shell cylinder section radius, θsh is the fiber yarn winding angle at the corresponding parallel circle of the head, θsc is the fiber yarn winding angle of the cylinder section.

4. The method of claim 2, wherein the method further comprises: determining the material properties of the winding shell head structure based on the fiber layup. The projection width of the single fiber yarn of the winding shell head at any parallel circle wherein, R is the radius of any parallel circle of the shell head, is the fiber yarn winding angle at the corresponding parallel circle of the head.

5. The method of claim 2, wherein the method further comprises: determining the material properties of the winding shell head structure by considering the fiber cross-overs. the effective projection of the single fiber yarn at any parallel circle of the winding shell head structure, i.e. the width of the area without interlacing, overlapping wherein: is the fiber yarn width, is the winding angle of the fiber yarn of the barrel section, is the radius of any parallel circle of the shell head, is the radius of the barrel section of the shell.

6. The method of claim 1, wherein: The , is the thickness of the fiber yarn, is the angle between the fiber yarn and the parallel circle, is the resin triangular area correction factor, is the total number of fiber yarns passing through the shell barrel section at any parallel circle, is the winding angle of the fiber yarn of the barrel section, is the winding angle of the fiber yarn of the head corresponding to the parallel circle.

7. The method of claim 6, wherein the method further comprises: determining the material properties of the winding shell head structure based on the fiber layup. The total number of fiber yarns passing through any parallel circle of the shell barrel section wherein: R is the radius of the shell barrel section, θ is the winding angle of the fiber yarn of the barrel section, W is the fiber yarn width.

8. The method of claim 1, wherein: The step 5 calculates the material performance parameters at different parallel circle radii of the head using the following formula: wherein Eeff,parallel is the equivalent elastic modulus of the head material in the direction parallel to the fibers, Eeff,perp is the equivalent elastic modulus of the head material in the direction perpendicular to the fibers, Ecf,parallel is the elastic modulus of the carbon fibers in the direction parallel to the fibers, Ecf,perp is the elastic modulus of the carbon fibers in the direction perpendicular to the fibers, Eres is the elastic modulus of the resin matrix; Geff,parallel is the equivalent in-plane shear modulus of the head material, Geff,perp is the equivalent out-of-plane shear modulus of the head material, Gcf,parallel is the in-plane shear modulus of the carbon fibers, Gcf,perp is the out-of-plane shear modulus of the carbon fibers, Gres is the shear modulus of the resin matrix; Peff,parallel is the in-plane equivalent Poisson’s ratio of the head material, Peff,perp is the out-of-plane equivalent Poisson’s ratio of the head material, Pcf,parallel is the in-plane Poisson’s ratio of the carbon fibers, Pcf,perp is the out-of-plane Poisson’s ratio of the carbon fibers, Pres is the Poisson’s ratio of the resin matrix; Vf is the fiber volume fraction, Vr is the resin volume fraction; , , , is an empirical parameter.

9. The method of claim 8, wherein the method further comprises: determining a material property of the winding shell closure structure based on the determined fiber layup. The empirical parameters , , The calculation of the empirical parameters is: 。 10. The method of predicting the performance of a winding head structure material of a fiber interlaced overhead winding shell according to any one of claims 1 to 9, characterized in that: Considering the volume fraction of the overhead area of the shell head region caused by the winding process and calculating the equivalent material parameters, a finite element model of the winding shell considering the fiber staggered overhead is further established, an internal pressure load is applied to simulate the working condition of the winding shell under the internal pressure load, and the material performance prediction of the winding shell head structure is realized.

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