Woven ceramic matrix composite structural member modeling method considering real structure

Abstract

The invention discloses a modeling method for a woven ceramic matrix composite structural member considering a real structure, and belongs to the technical field of three-dimensional model reconstruction.The modeling method includes the steps that firstly, fiber bundles in an XCT image are subjected to matching numbering; different colors are given to different fiber bundles, and visualization of numbers is achieved; relevant geometric information of each fiber bundle is extracted according to the colors of the fiber bundles; then establishing a single fiber bundle through a sweeping method; and finally, all the fiber bundles are spliced to form a model capable of reflecting the real woven ceramic matrix composite structural member, and the model is higher in trueness and better conforms to the actual situation. Besides, according to the method, hundreds of fiber bundles can be rapidly matched and marked at a time, the problems that an existing matching algorithm is low in efficiency and large in computing resource consumption are solved, and the method is suitable for matching and numbering tasks of the fiber bundles in CMC woven structural parts such as tenons.

Description

Technical Field

[0001] The present invention belongs to the field of three-dimensional model reconstruction, and relates to a method for establishing a model of a woven ceramic matrix composite structural member, and particularly relates to a method for modeling a woven ceramic matrix composite structural member considering the real structure. Background Art

[0002] Ceramic matrix composites (hereinafter referred to as CMC) have a much lower density than metal materials and have good high-temperature properties, and are ideal materials for hot-end components of a new generation of high-performance aeroengines. At present, CMC structural members manufactured by a weaving method have not been widely used in high-temperature components of aeroengines because their strength cannot be accurately predicted. In order to predict the strength of a structural member, finite element simulation needs to be carried out on the corresponding structural member. Finite element simulation first requires establishing a model and then performing simulation calculations. The accuracy of the established model determines the accuracy of the simulation calculation. Therefore, it is very important to establish a real structure model for woven CMC structural members.

[0003] XCT is a non-destructive testing method that can obtain the real internal structure of a woven CMC structural member without damaging the material. The model established based on XCT can more realistically reflect the mesoscopic structure of the material. Domestic and foreign scholars have found that the prediction accuracy of the model established by using XCT is higher than that of the ideal voxel method. Some scholars have proposed a mesoscopic structure modeling method for the 2.5D woven structure of CMC (such as the patent publication number CN106469454A, "A computer graphics recognition technology and three-dimensional modeling method for the mesoscopic structure of a composite material"). Some studies have shown that establishing a model containing pores based on XCT images to predict the tensile modulus and structural failure mode of materials, and compared with the idealized model, the prediction results are more accurate (Yang T, Qiu H, Liu X, et al. Micro-CT Based Statistical Geometry Modeling and Numerical Verification of 2.5D Sic f / Sic Composite [J]. Applied Composites Materials, 2021, 28(3): 835-854.). However, manual participation is required in the process of establishing these models, and the modeling efficiency is low, which is not suitable for structural members with a large number of fiber bundles and complex arrangements.

[0004] The parametric modeling method can establish a model by setting established parameters and can achieve the automatic establishment of the model through programming, with relatively high modeling efficiency. Currently, there are already methods for establishing the mesoscopic model of the plain weave composite material preform (such as the "Method for Establishing the Mesoscopic Model of the Plain Weave Composite Material Preform" with the patent publication number CN 111310366A) and the method for establishing the RVE model of the fiber bundle change (such as the "Parametric Modeling Method for the RVE of the Braided Composite Material Considering the Geometric Change of the Yarn" with the patent publication number CN117350058A). However, these methods are proposed based on the design of CMC materials and require manual input of parameters. The established models are too ideal and cannot truly reflect the actual structure of the CMC structural components.

[0005] Therefore, it is necessary to specifically design a corresponding model establishment method for the braided CMC structural components based on the parametric modeling method. Using this method, the relevant geometric parameters of the real fiber bundle can be extracted from the XCT image, and the automatic reconstruction of the fiber bundle model can be quickly completed, so as to combine into a braided structural component model that conforms to the actual situation. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a modeling method for the braided ceramic matrix composite material structural components considering the real structure in view of the above-mentioned existing deficiencies.

[0007] To achieve the above technical purpose, the technical solution adopted by the present invention is as follows:

[0008] A modeling method for the braided ceramic matrix composite material structural components considering the real structure, comprising the following steps:

[0009] Step 1: Obtain the XCT images of the warp and weft of the braided ceramic matrix composite material structural components respectively, identify and segment the fiber bundles, and mask the cross-sections of the fiber bundles in the XCT images;

[0010] Step 2: For the CT images after the identification and segmentation of the warp and weft, number each fiber bundle in each image using the connected component labeling method, and calculate the geometric center points of each fiber bundle. The cross-section numbers of the first CT image of the warp and weft are arbitrary, and the cross-section numbers of the fiber bundles in other images must be re-numbered after matching with the cross-sections of the fiber bundles in the previous image;

[0011] Step 3: Design a marker visualization function, convert the numbers of each fiber bundle into RGB values, assign different colors to the cross-sections of the fiber bundles in the CT, and realize the visualization of the fiber bundle matching markers;

[0012] Step 4: Extract the in-plane geometric parameter information of each cross-section of each fiber bundle in the CT image according to different RGB values,

[0013] Step 5: Based on the B-spline curve, take the center points of each cross-section as control points, and fit the guiding lines of each fiber bundle as the out-of-plane geometric information of the fiber bundle;

[0014] Step 6: Consider the cross-section of the fiber bundle as an ellipse, take the center point as the center of the ellipse, and the values of the major axis and minor axis of the ellipse are equal to the width and height values of the circumscribed rectangle of the cross-section. Combine the in-plane geometric parameter information of each cross-section of each fiber bundle in the CT image to draw each cross-section of each fiber bundle. Use the guiding line as the sweeping path, and establish the single fiber bundle models of all warp and weft yarns respectively by the sweeping method;

[0015] Step 7: Piece together all the established single models to form the final model that can reflect the true structure of the braided ceramic matrix composite structural component.

[0016] To optimize the above technical solutions, the specific measures taken also include:

[0017] In Step 1, in adjacent slices of the same fiber bundle, when the cross-section of the fiber bundle in the latter slice is projected onto the former slice, there is an intersecting part with the cross-section of the fiber bundle in the former slice, and at this time, the distance between the adjacent two slices does not exceed 3 times the size of the pixels in the slice.

[0018] In step 2, by creating three-dimensional indexes corresponding to the front and rear CT images and a distance retrieval table of the center points of the fiber bundle cross-sections in the two CT images, and re-numbering after fiber bundle cross-section matching according to the three cases of adding yarn, subtracting yarn, and continuity. Among them, adding yarn means that a certain fiber bundle cross-section that appears in the latter CT image has no corresponding cross-section in the former CT image; subtracting yarn means that a certain fiber bundle cross-section that appears in the former CT image does not appear in the latter CT image; continuity means that a certain fiber bundle cross-section in the latter CT image has a unique corresponding fiber bundle cross-section in the former CT image. At this time, the value at the corresponding position in the distance retrieval table is the minimum value of its row and column. The specific method for re-numbering the fiber bundle cross-sections in a certain CT slice after matching is as follows: create two three-dimensional indexes respectively. The first and second three-dimensional indexes store the information of the fiber bundles in the front and rear images respectively. The first dimension of each three-dimensional index stores the numbers of all current fiber bundles in the order of numbering, the second dimension stores the central abscissa values corresponding to the fiber bundle cross-sections, and the third dimension stores the central ordinate values corresponding to the fiber bundle cross-sections. Create a distance retrieval table, the rows of which represent the fiber bundle numbers in the latter image, and the columns represent the fiber bundle numbers in the former image. The Euclidean distances between the center points of each fiber bundle cross-section in the latter image and the center points of each fiber bundle cross-section in the former image are stored in the distance retrieval table. Calculate the relevant Euclidean distances according to the center coordinates of each cross-section obtained by the connected component labeling method and fill them into the above distance retrieval table. Regard the fiber bundle cross-section as an ellipse, and use one-tenth of the average major axis length of all cross-sections belonging to the fiber bundle as the threshold to judge the cases of adding yarn and fiber bundle continuity. For a column in the distance retrieval table, if the minimum value of this column is greater than or equal to the established threshold, then regard the fiber bundle cross-section corresponding to this column as adding yarn; if the minimum value of this column is less than the established threshold but not the minimum value in its corresponding row, then also regard the fiber bundle cross-section corresponding to this column as adding yarn; if the minimum value of this column is less than the established threshold and is also the minimum value in the corresponding row, then regard the fiber bundle cross-section corresponding to this column as continuous. For the fiber bundle cross-section of adding yarn, set a new number to replace the fiber bundle number corresponding to the second three-dimensional index. For the fiber bundle cross-section of continuity, use the fiber bundle number matched in the first three-dimensional index to replace the corresponding fiber bundle number in the second three-dimensional index. Judge each column of the distance retrieval table according to the above method, so as to complete the matching numbering of the fiber bundle cross-sections in the latter CT image, and use this method to perform matching marking on the fiber bundle cross-sections in all CT images except the first CT image.

[0019] In step 3, the number of fiber bundles in the woven ceramic matrix composite structural part is less than 1000. The R, G, and B channel values can be completely represented by only two of the channels. Let the B channel value of the warp yarn be constantly 255, and the R channel value of the weft yarn be constantly 255.

[0020] In step 3, the specific method for realizing the visualization of fiber bundle matching marks is: constructing a warp yarn number visualization function: At the same time, construct a visualization function for the weft yarn numbering: in "%" represents rounding down, and "%" represents remainder. After the decimal number is converted into RGB value through the above number visualization function, the fiber bundle cross section in the warp and weft CT images are colored respectively to realize number visualization.

[0021] In step 4, the in-plane geometric parameter information of each section of each fiber bundle in the CT image includes the width w and height h of the section, the coordinates of the center point of the section (a, b, c) and the main direction angle θ. The range of the main direction angle is (-90°, 90°), and it is stipulated that the width of the circumscribed rectangle is always greater than the height of the circumscribed rectangle.

[0022] In step 4, the specific method for obtaining the in-plane geometric parameter information of each cross section of each fiber bundle in the CT image is as follows:

[0023] By formula Calculate the average vector (x0, y0) in the fiber bundle cross section, where x and y are the horizontal and vertical coordinates of each pixel point in the fiber bundle cross section, R is the set of all pixel points in the fiber bundle cross section, and n is the total number of pixel points in the fiber bundle cross section. The horizontal and vertical coordinates of each point in the cross section and the average vector are obtained by the formula Calculate the directional deviation moment m 11 、m 20 、m 02 , substituting these directional deviation moments into the formula The main direction angle θ is calculated, and finally the horizontal and vertical coordinates of the center point and the main direction angle are calculated according to the formula Each pixel point in the fiber bundle cross section is rotated counterclockwise by θ degrees around the center point of the fiber bundle cross section to obtain the horizontal coordinate x' and vertical coordinate y' of each pixel point after the rotation transformation. After the fiber bundle cross section is straightened by the above rotation transformation, according to the formula w = x' max -x' min ,h=y' max -y' min , x′ max is the maximum value of the horizontal coordinate after transformation, x′ min is the minimum value of the horizontal coordinate after transformation, y′ max is the maximum value of the ordinate after transformation, y′ min The minimum value of the ordinate after transformation is the minimum value, and the difference between the maximum and minimum values ​​of the abscissa and ordinate after transformation is calculated as the width w and height h of the section.

[0024] In Step 5, the type of the B-spline curve used is a fourth-order quasi-uniform B-spline curve, so that the first and last points of the fiber bundle guiding line always coincide with the midpoints of the first and last cross-sections of the fiber bundle.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0026] 1. When modeling a single fiber bundle, compared with the existing methods, first, the fiber bundles in the XCT images are matched and numbered; then, different colors are assigned to different fiber bundles to realize the visualization of the numbers; then, the relevant geometric information of each fiber bundle is extracted according to the colors of the fiber bundles; then, a single fiber bundle is established by the sweeping method; finally, all the fiber bundles are spliced to form a model that can finally reflect the real structure of the woven ceramic matrix composite material, and this model has a higher degree of authenticity and is more in line with the actual situation.

[0027] 2. A method for matching and labeling fiber bundles by establishing two three-dimensional indexes and a distance retrieval table is proposed for the first time. The principle of this method is simple, and only two cases of increasing yarn and continuous cross-sections of the fiber bundle need to be considered, which improves the matching efficiency. Therefore, hundreds of fiber bundles can be quickly matched and marked at one time, solving the problems of low efficiency and large consumption of computing resources of the current matching algorithm, and being applicable to the matching and numbering tasks of fiber bundles in CMC woven structural parts such as tenons.

[0028] 3. The proposed number visualization function colors the cross-sections of the fiber bundles in the CT by converting the decimal number value into a 256-based RGB value, realizing the visualization of the fiber bundle numbers for the first time. And by fixing the value of one channel to 255, the warp and weft yarns are distinguished, which is convenient for subsequent extraction of the relevant geometric parameters of the fiber bundles, helps to reduce the retrieval time of the fiber bundles, and improves the modeling efficiency.

[0029] 4. The present invention determines the directions of different fiber bundle cross-sections by using the principal direction angle for the first time, so that a fiber bundle model in the real woven ceramic matrix composite material structure can be established. And the B-spline curve is used to simulate the real trend of the fiber bundle, thereby improving the accuracy of the established model of the woven ceramic matrix composite material structure.

[0030] 5. The fiber bundle matching and marking method, number visualization method, acquisition of fiber bundle cross-section geometric parameters, determination of the guiding line, and establishment of a single fiber bundle in the present invention can all be realized by programming. The present invention can automatically establish a model reflecting the real woven ceramic matrix composite material structure within one hour through a computer program, while the existing model establishment methods all require manual participation, and it takes at least one week to establish a model of a woven ceramic matrix composite material structure of the same size. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1Flow chart of a modeling method for a woven ceramic matrix composite structural member considering the actual structure in the present invention;

[0032] Figure 2 Is the CT image of the identified and segmented warp cross-section;

[0033] Figure 3 Is the CT image of the identified and segmented weft cross-section;

[0034] Figure 4 Is the three-dimensional index t1 for storing the fiber bundle cross-section information in the previous CT image;

[0035] Figure 5 Is the three-dimensional index t2 for storing the fiber bundle cross-section information in the next CT image;

[0036] Figure 6 Is the distance retrieval table td for storing the distances between the center points of the fiber bundle cross-sections in the front and back CT images;

[0037] Figure 7 Is the change in the fiber bundle cross-section number in the three-dimensional index t2 when the fiber bundle cross-section is an added yarn;

[0038] Figure 8 Is the change in the fiber bundle cross-section number in the three-dimensional index t2 when the fiber bundle cross-section is continuous;

[0039] Figure 9 Is the warp yarn diagram colored with the number visualization function;

[0040] Figure 10 Is the weft yarn diagram colored with the number visualization function;

[0041] Figure 11 Is the in-plane and out-of-plane geometric information of the fiber bundle required to be obtained from the CT image;

[0042] Figure 12 Are all the established single warp yarn models;

[0043] Figure 13 Are all the established single weft yarn models;

[0044] Figure 14 Is the final model that reflects the actual tenon structure formed by splicing and combining all single fiber bundles. Detailed implementation method

[0045] In order to make the objectives, technical solutions and advantages of the present application more clear and understandable, the present application will be described and explained below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments provided in the present application without creative efforts fall within the scope of protection of the present application.

[0046] Obviously, the accompanying drawings in the following description are only some examples or embodiments of the present application. For those of ordinary skill in the art, without creative efforts, the present application can also be applied to other similar scenarios based on these drawings. In addition, it can also be understood that although the efforts made in this development process may be complex and lengthy, however, for those of ordinary skill in the art related to the content disclosed in the present application, some design, manufacturing or production changes based on the technical content disclosed in the present application are only conventional technical means and should not be understood as the content disclosed in the present application being insufficient.

[0047] Referring to "embodiments" in the present application means that the specific features, structures or characteristics described in connection with the embodiments may be included in at least one embodiment of the present application. The phrase appears in various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those of ordinary skill in the art explicitly and implicitly understand that the embodiments described in the present application can be combined with other embodiments without conflict.

[0048] Unless otherwise defined, the technical terms or scientific terms involved in this application shall have the ordinary meanings understood by those with ordinary skills in the technical field to which this application belongs. The words such as "a", "an", "one kind", "the" and the like involved in this application do not indicate a quantity limitation and may represent a singular or plural number. The terms "including", "comprising", "having" and any variations thereof involved in this application are intended to cover non-exclusive inclusion; for example, a process, method, system, product or device that includes a series of steps or units (units) is not limited to the listed steps or units, but may further include steps or units not listed, or may further include other steps or units inherent to these processes, methods, products or devices. The words such as "connected", "coupled" and the like involved in this application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The "multiple" / "several" involved in this application refers to two or more. "And / or" describes the association relationship of associated objects and indicates that three relationships may exist. For example, "A and / or B" may represent: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally represents an "or" relationship between the associated objects before and after. The terms "first", "second", "third" and the like involved in this application are only used to distinguish similar objects and do not represent a specific order for the objects.

[0049] As Figure 1 shown, this embodiment provides a modeling method for a woven ceramic matrix composite structural member considering the real structure. Taking a 2.5D woven CMC tenon structural member as an example, the model is reconstructed by the above method, including the following steps:

[0050] Step 1: Use XCT technology to scan the tenon structural member, obtain a CT image reflecting the internal fiber bundle structure, and identify and segment the fiber bundle cross-sections in the warp and weft CT images, as Figure 2 and Figure 3 shown.

[0051] Step 2: Match and number the warps and wefts identified and segmented in the CT image respectively. The specific steps are as follows:

[0052] First, use the connected region labeling method to randomly number each fiber bundle cross-section in the CT image and obtain the center coordinates of each cross-section. Then, as Figure 4 and Figure 5 shown, construct a three-dimensional index t1 and a three-dimensional index t2 to store the numbers of each fiber bundle cross-section, the abscissa of the cross-section center point, and the ordinate of the cross-section center point in the previous and the next CT images of two adjacent CT images respectively. Then, as Figure 6As shown in the figure, create a distance retrieval table td to store the Euclidean distances between the central points of each fiber bundle cross-section in the subsequent image and the central points of each fiber bundle cross-section in the previous image. Then determine the threshold for judging the yarn addition and continuity of the fiber bundle cross-sections. Finally, retrieve the minimum value of each column in td column by column, and use this as the judgment basis to match numbers for the fiber bundle cross-sections in the subsequent image. Taking column j in td as an example, obtain its minimum value a mj . Compare a mj with all elements in the m-th row. If a mj is not the minimum value in the m-th row, then cross-section j is a yarn addition in the subsequent CT image; if a mj is the minimum value in the m-th row but the value of a mj exceeds the set threshold, cross-section j is also regarded as a yarn addition. For the above two cases where the fiber bundle cross-sections are yarn additions, a new number n1 + k needs to be added in t2 to replace number j. As shown in Figure 7 , where k represents the number of yarn additions found so far. If a mj is the minimum value in the m-th row and the value of a mj is within the set threshold range, the fiber bundle cross-section is considered continuous, and number m needs to be used in t2 to replace the original number of cross-section j. As shown in Figure 8 .

[0053] According to the above method, match each fiber bundle cross-section in all CT images except the first image in the warp and weft CT images respectively, and complete the re-numbering.

[0054] Step Three: Visualize the fiber bundles with the matched numbers.

[0055] Construct a visualization function for the numbers of the warp yarns: At the same time, construct a visualization function for the numbers of the weft yarns: where represents rounding down, and "%" represents taking the remainder. After converting the decimal numbers to RGB values through the above number visualization functions, color the fiber bundle cross-sections in the warp and weft CT images respectively to achieve number visualization. The visualization effect diagrams of the numbers of the warp and weft yarns are as shown in Figure 9 and Figure 10 .

[0056] Step Four: Extract the in-plane geometric information of all cross-sections of each fiber bundle according to the RGB values of the fiber bundle cross-sections in each CT image. As shown in Figure 11 , the obtained in-plane geometric information includes: the width w and height h of the cross-section, the coordinates (a, b, c) of the cross-section center point and the main direction angle θ. The specific steps are as follows:

[0057] First, in step 2, the horizontal coordinate a and vertical coordinate b of the center point of each fiber bundle cross section have been obtained by the connected region method, and c is the height of the CT image where the current fiber bundle cross section is located, which can be obtained from the parameters of the XCT scan in step 1, thereby determining the coordinates (a, b, c) of the fiber bundle cross section in space. Secondly, by the formula Calculate the average vector (x0, y0) in the fiber bundle cross section, and use the horizontal and vertical coordinates of each point in the cross section and the average vector by the formula Calculate the directional deviation moment m 11 、m 20 、m 02 , substituting these directional deviation moments into the formula Calculate the main direction angle θ. Finally, according to the horizontal and vertical coordinates of the center point and the main direction angle according to the formula After the fiber bundle cross section is straightened by rotation transformation, according to the formula w = x' max -x' min ,h=y' max -y' min , calculate the difference between the maximum and minimum values ​​of the horizontal and vertical coordinates after the transformation as the width w and height h of the section.

[0058] According to the above steps, the in-plane geometric information of all fiber bundle cross sections in the warp yarn and the weft yarn is extracted in turn.

[0059] Step 5: Determine the out-of-plane geometric information of each fiber bundle. Figure 11 As shown, the out-of-plane geometric information of the fiber bundle is the guiding line of the fiber bundle.

[0060] Based on the fourth-order quasi-uniform B-spline curve, the center point of each cross section in each fiber bundle is used as a control point to determine the guide lines of all fiber bundles.

[0061] Step 6: Construct single fiber bundle models of warp and weft yarns respectively.

[0062] The fiber bundle cross section is regarded as an ellipse, and the center point is taken as the center of the ellipse. The values ​​of the major axis and minor axis of the ellipse are equal to the values ​​of the width and height of the circumscribed rectangle of the cross section. The size of each cross section of each fiber bundle in the CT image is determined by combining the main direction angle. The guide line is used as the sweeping path, and the single fiber bundle models of all warp and weft yarns are established by the sweeping method, and the tenon part is selected and saved in the stp file format. The established single fiber bundle models of all warp and weft yarns are shown in Figure 12 and Figure 13 shown.

[0063] Step 7: Combine and splice the constructed single fiber bundle models into the final tenon model.

[0064] Import the stp files of all single fiber bundles of warp and weft into the SpaceClaim 2022R1 software and combine them into the final tenon model, as Figure 14 shown.

[0065] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited by the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention shall be equivalent replacement methods and are all included in the protection scope of the present invention.

Claims

1. A modeling method for a woven ceramic matrix composite structural component considering the real structure, characterized in that: The following steps are involved: Step 1: Obtain the XCT images of the warp and weft of the woven ceramic matrix composite structural component respectively, identify and segment the fiber bundles, and mask the cross-section of the fiber bundles in the XCT image; Step 2: For the CT images after identification and segmentation of warp and weft yarns, use the connected labeling method to number each fiber bundle in each image, and calculate the geometric center point of each fiber bundle. The cross-section numbering in the first CT image of the warp and weft yarns is arbitrary. In addition, the cross-section numbers of fiber bundles in other images must be matched with the cross-sections of fiber bundles in the previous image and then renumbered; Step 3: Design a label visualization function to convert each fiber bundle number into an RGB value, assign different colors to the fiber bundle cross-section in CT, and realize the visualization of fiber bundle matching labels; Step 4: Extract the in-plane geometric parameter information of each fiber bundle in each section of the CT image according to different RGB values. Step 5: Based on the B-spline curve, the center point of each cross section is used as the control point, and the guide line of each fiber bundle is fitted as the out-of-plane geometric information of the fiber bundle; Step 6: The cross section of the fiber bundle is regarded as an ellipse, and the center point is taken as the center of the ellipse. The values ​​of the major axis and the minor axis of the ellipse are equal to the values ​​of the width and height of the circumscribed rectangle of the cross section. Combined with the in-plane geometric parameter information of each cross section of each fiber bundle in the CT image, each cross section of each fiber bundle is drawn. The guide line is used as the sweeping path, and the single fiber bundle models of all warp yarns and weft yarns are established by the sweeping method. Step 7: All the established single models are spliced ​​and combined into a final model that can reflect the real structure of the woven ceramic matrix composite structural parts.

2. A method for modeling a woven ceramic matrix composite structural component considering a real structure according to claim 1, characterized in that: In step 1, in adjacent slices of the same fiber bundle, when the cross section of the fiber bundle in the latter slice is projected onto the previous slice, there is an intersecting portion with the cross section of the fiber bundle in the previous slice, and at this time, the distance between the two adjacent slices does not exceed 3 times the size of the pixels in the slice.

3. A method for modeling a woven ceramic matrix composite structural component considering a real structure according to claim 1, characterized in that: In step 2, by creating a three-dimensional index corresponding to the two CT images before and after and a distance retrieval table of the center points of the fiber bundle cross sections in the two CT images, the fiber bundle cross sections are matched and renumbered according to the three situations of yarn addition, yarn reduction and continuity. Among them, yarn addition means that a fiber bundle cross section appearing in the latter CT image has no corresponding cross section in the previous CT image; yarn reduction means that a fiber bundle cross section appearing in the previous CT image has no corresponding cross section in the latter CT image; continuity means that a fiber bundle cross section in the latter CT image has a unique corresponding fiber bundle cross section in the previous CT image. At this time, the distance retrieval table The value at the corresponding position is the minimum value of its row and column. The specific method for renumbering the fiber bundle cross section after matching in a CT slice is as follows: create two three-dimensional indexes respectively, and the first and second three-dimensional indexes store the information of the fiber bundles in the previous and next two pictures respectively: the first dimension of each three-dimensional index stores the numbers of all current fiber bundles in numerical order, the second dimension stores the central horizontal coordinate value corresponding to each fiber bundle cross section, and the third dimension stores the central vertical coordinate value corresponding to each fiber bundle cross section. Create a distance retrieval table, whose rows represent the fiber bundle numbers in the next picture, and whose columns represent the fiber bundle numbers in the previous picture. The distance retrieval table The table stores the Euclidean distance between the center point of each fiber bundle cross section in the latter figure and the center point of each fiber bundle cross section in the previous figure. According to the center coordinates of each cross section obtained by the connected marking method, the relevant Euclidean distance is calculated and filled into the above distance search table. The fiber bundle cross section is regarded as an ellipse, and one tenth of the average main axis length of all cross sections belonging to the fiber bundle is used as the threshold to judge the continuity of the added yarn and the fiber bundle. For a column of the distance search table, if the minimum value of this column is greater than or equal to the established threshold, the fiber bundle cross section corresponding to this column is regarded as the added yarn; if the minimum value of this column is less than the established threshold but is not the minimum value in its corresponding row, the fiber corresponding to this column is also regarded as The fiber bundle cross section is an added yarn; if the minimum value of this column is less than the established threshold and is also the minimum value in the corresponding row, the fiber bundle cross section corresponding to this column is regarded as continuous. For the fiber bundle cross section that is an added yarn, a new number is set to replace the fiber bundle number corresponding to the second three-dimensional index. For the continuous fiber bundle cross section, the fiber bundle number matched in the first three-dimensional index is used to replace the corresponding fiber bundle number in the second three-dimensional index. Each column of the distance retrieval table is judged according to the above method to complete the matching number of the fiber bundle cross section in the next CT image. This method is used to mark the matching number of the fiber bundle cross sections in other than the first CT image.

4. A method for modeling a woven ceramic matrix composite structural component considering a real structure according to claim 1, characterized in that: In step three, there are less than 1000 fiber bundles in the woven ceramic-based composite material structure. Only two of the three channels R, G, and B can fully represent the numbering of all fiber bundles, so that the B channel value of the warp yarn is always 255, and the R channel value of the weft yarn is always 255.

5. A method for modeling a woven ceramic matrix composite structural component considering a real structure according to claim 1, characterized in that: In step 3, the specific method for realizing the visualization of fiber bundle matching marks is: constructing a warp yarn number visualization function: At the same time, construct a visualization function for the weft yarn numbering: in "%" represents rounding down, and "%" represents remainder. After the decimal number is converted into RGB value by the above number visualization function, the fiber bundle cross section in the warp and weft CT images are colored respectively to realize number visualization.

6. A method for modeling a woven ceramic matrix composite structural component considering a real structure according to claim 1, characterized in that: In step 4, the in-plane geometric parameter information of each section of each fiber bundle in the CT image includes the width w and height h of the section, the coordinates of the center point of the section (a, b, c) and the main direction angle θ. The range of the main direction angle is (-90°, 90°), and it is stipulated that the width of the circumscribed rectangle is always greater than the height of the circumscribed rectangle.

7. A method for modeling a woven ceramic matrix composite structural component considering a real structure according to claim 6, characterized in that: In step 4, the specific method for obtaining the in-plane geometric parameter information of each cross section of each fiber bundle in the CT image is as follows: By formula Calculate the average vector (x0, y0) in the fiber bundle cross section, where x and y are the horizontal and vertical coordinates of each pixel point in the fiber bundle cross section, R is the set of all pixel points in the fiber bundle cross section, and n is the total number of pixel points in the fiber bundle cross section. The horizontal and vertical coordinates of each point in the cross section and the average vector are obtained by the formula Calculate the directional deviation moment m 11 、m 20 、m 02 , substituting these directional deviation moments into the formula The main direction angle θ is calculated, and finally the horizontal and vertical coordinates of the center point and the main direction angle are calculated according to the formula Each pixel point in the fiber bundle cross section is rotated counterclockwise by θ degrees around the center point of the fiber bundle cross section to obtain the horizontal coordinate x' and vertical coordinate y' of each pixel point after the rotation transformation. After the fiber bundle cross section is straightened by the above rotation transformation, according to the formula w = x' max -x' min ,h=y' max -y' min , x′ max is the maximum value of the horizontal coordinate after transformation, x′ min is the minimum value of the horizontal coordinate after transformation, y′ max is the maximum value of the ordinate after transformation, y′ min The minimum value of the ordinate after transformation is the minimum value, and the difference between the maximum and minimum values ​​of the abscissa and ordinate after transformation is calculated as the width w and height h of the section.

8. A method for modeling a woven ceramic matrix composite structural component considering a real structure according to claim 1, characterized in that: In step 5, the type of B-spline curve used is a fourth-order quasi-uniform B-spline curve, so that the first and last points of the fiber bundle guide line always coincide with the midpoints of the first and last cross sections of the fiber bundle.

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