Ceramic matrix composite blade crown-shaft structure based on three-dimensional orthogonal weaving process

Abstract

The application discloses a ceramic matrix composite blade crown-blade body structure based on a three-dimensional orthogonal weaving process, comprising a blade crown and a blade body, the blade crown comprises an upper edge plate, the tail edge of the blade body is connected with the blade crown, the upper edge plate comprises upper edge plate warp yarns and upper edge plate weft yarns, the blade body comprises blade body warp yarns and blade body weft yarns, at least part of the blade body warp yarns in the blade body are divided into two groups averagely according to the direction of one side of a blade pot curve and one side of a blade back curve after being led out from one end matched with the upper edge plate, the blade body warp yarns in the same group are combined to form two bundles of upper edge plate joint yarns, participate in the weaving of the upper edge plate, the upper edge plate joint yarns pass through the gap between the upper edge plate warp yarns, and the three-dimensional orthogonal weaving is carried out together with the upper edge plate warp yarns and the upper edge plate weft yarns to form an interlocking structure. The blade body and the blade crown adopt different weaving modes according to the load and the shape characteristics, the adaptability of the material and the structure is improved, the three-dimensional orthogonal weaving and the yarn combining method are adopted, and the connecting strength between the blade body and the blade crown is improved.

Description

Technical Field

[0001] This invention relates to the technical field of composite materials, and more particularly to a ceramic matrix composite blade crown-blade structure based on a three-dimensional orthogonal weaving process. Background Technology

[0002] Ceramic matrix composites (CMCs) exhibit excellent performance in various applications, including aerospace vehicles, aero engines, nuclear protection, and braking systems, due to their superior mechanical, electronic, and oxidation resistance properties. In these applications, the use of CMCs has been proven to significantly improve the thrust-to-weight ratio and efficiency of aero engines. Studies have shown that using CMCs in hot-end components such as combustion chambers, turbines, afterburners, and nozzles can increase engine operating temperatures by 300-500 degrees Celsius, reduce structural weight by 50-70%, and increase thrust by 30%-100%.

[0003] The blade crown structure is mainly found on low-pressure turbine rotor blades, which operate at relatively low speeds. Because turbine rotor blades must withstand not only the influence of the thermal environment but also speeds ranging from thousands to tens of thousands of revolutions per minute, the strength requirements are even more stringent. As anisotropic composite materials, CMCs exhibit significant performance differences in various directions. To fully realize the material potential of CMCs, it is essential to design the blade crown-blade structure at a microscale, taking into account both the material properties and the structural stress characteristics.

[0004] However, current publicly available literature on CMC (Chemical Miturbine Components) blade-blade structure design mostly considers only the macroscopic shape of the structure, lacking design for the microscopic woven structure. Furthermore, the connection between the blade and blade is generally achieved through stitching, welding, or pinning. This method increases the structural complexity and can damage the internal fibers during fabrication. Considering the significant difference in shape between the blade and blade and their obvious microscopic aperiodicity, how to achieve integral weaving of the blade and blade and effectively transition the fiber bundles between structures to maximize the overall performance of the structure and materials is a major challenge hindering the design of CMC turbine rotor structures. Summary of the Invention

[0005] The technical problem to be solved by this invention is to address the shortcomings of the prior art by providing a ceramic matrix composite (CMC) crown-blade structure based on a three-dimensional orthogonal weaving process. Compared to existing CMC crown-blade structures, the structure in this patent employs an integrated micro-weaving method to ensure the continuity of fiber bundles between the blade and the crown; different weaving methods are used for the blade and crown to suit different load and shape characteristics, improving the adaptability of the material and structure; and the use of three-dimensional orthogonal weaving and yarn merging methods enhances the connection strength between the blade and the crown.

[0006] To achieve the above-mentioned technical objectives, the technical solution adopted by the present invention is as follows:

[0007] A ceramic matrix composite leaf crown-blade structure based on a three-dimensional orthogonal weaving process includes a leaf crown and a blade. The leaf crown includes an upper edge plate, and the trailing edge of the blade connects to the leaf crown. The upper edge plate includes upper edge plate warp and upper edge plate weft yarns, and the blade includes blade blade warp and blade blade weft yarns. The upper edge plate warp and upper edge plate weft yarns are interwoven, and the blade blade warp and blade blade weft yarns are interwoven. The blade has a longitudinal section consisting of two long curves and two short arcs, forming an aerodynamic profile. The two long curves are the blade base curve and the blade back curve, and the two short arcs are the blade leading edge and the blade trailing edge. The blade back curve is a protruding section in the profile, forming the suction surface of the blade. The blade base... The curve is the concave section in the contour, forming the pressure surface of the blade. The ends of the blade basin curve and the blade back curve are connected by the leading edge and trailing edge of the blade, respectively. The short arc in the direction of gas flow is the leading edge of the blade, and the short arc in the direction of gas outflow is the trailing edge of the blade. At least part of the blade warp yarns are drawn out from the end that mates with the upper edge plate and are divided into two groups equally in the direction of the side where the blade basin curve is located and the side where the blade back curve is located. The blade warp yarns in the same group are merged to form two bundles of upper edge plate knotting yarns, which participate in the weaving of the upper edge plate. The upper edge plate knotting yarns pass through the gaps between the upper edge plate warp yarns and are woven together with the upper edge plate warp yarns and upper edge plate weft yarns in three-dimensional orthogonal weaving to form an interlocking structure.

[0008] To optimize the above technical solution, the specific measures also include:

[0009] The aforementioned leaf crown includes sealing teeth, which are located on the upper surface of the upper edge plate. The sealing teeth include sealing tooth warp yarns and sealing tooth weft yarns. The sealing tooth warp yarns start from the outermost side of the upper edge plate, are drawn out from the uppermost part of the upper edge plate weft yarns near the center of the leaf crown, and bend upwards. The sealing tooth warp yarns interweave and wrap between the sealing tooth weft yarns to form the sealing teeth.

[0010] The upper and lower surfaces of the aforementioned upper edge plate are irregular curved surfaces along the circumference of the turbine where the blade is located. The edges of multiple blade upper edge plates distributed along the turbine circumference contact each other to form the upper wall of the turbine airflow channel. The upper edge plate extends along the turbine circumference and is perpendicular or nearly perpendicular to the leading edge of the blade.

[0011] The upper edge plate described above has serrated curved surfaces on both sides in the circumferential direction, and adjacent upper edge plates mesh with each other through the serrated curved surfaces.

[0012] The thickness of the upper edge plate mentioned above gradually decreases from the junction of the blade and the upper edge plate toward the serrated curved surface.

[0013] The aforementioned leaf body is woven using a 2D, 2.5D, or 3D twill weave method, wherein the warp yarns of the leaf body are woven along a direction perpendicular to the longitudinal section of the leaf body, and the weft yarns of the leaf body are woven along a direction parallel to the longitudinal section of the leaf body.

[0014] Of the aforementioned leaf warp yarns, only half are drawn out to participate in the weaving of the upper edge plate, while the remaining leaf warp yarns, which are on the same plane as the upper edge plate warp yarns, extend to the transition point between the leaf body and the upper edge plate and are cut off.

[0015] The warp yarns of the upper edge plate, the weft yarns of the upper edge plate, the warp yarns of the leaf body, and the weft yarns of the leaf body mentioned above are all made of ceramic matrix composite materials.

[0016] The aforementioned leaf crown is provided with two sealing grates, which are arranged parallel to each other.

[0017] The aforementioned closed-tooth warp yarns and closed-tooth weft yarns are both made of ceramic matrix composite materials.

[0018] The present invention has the following advantages:

[0019] 1. This invention discloses a microstructure of the blade crown-blade that matches material properties with structure and load. Compared with existing macroscopic designs, it can match the load transmission direction in the material with the optimal direction of material properties, and better bring out the excellent performance of CMCs.

[0020] 2. The CMCs leaf crown-blade structure in this invention adopts an integrated weaving method based on three-dimensional orthogonal weaving technology, which can effectively avoid fiber delamination caused by using a split weaving method, improve the overall rigidity of the structure, and avoid damage to the fibers caused by sewing, riveting and other reinforcement methods.

[0021] 3. The CMCs crown-blade structure in this invention solves the problem of yarn connection and transition between the blade and crown by using a yarn merging method, which can fully utilize the mechanical properties of continuous yarn and enhance the rigidity of the upper edge plate. It also has strong adaptability, allowing for the combination of various blade weaving structures without changing the crown weaving method. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the blade crown-blade structure of a turbine rotor.

[0023] Figure 2 This is a front view of a prefabricated ceramic matrix composite blade crown-blade structure.

[0024] Figure 3 A side view of a ceramic matrix composite blade crown-blade structure prefabrication.

[0025] Figure 4 Top view of a ceramic matrix composite blade crown-blade structure prefabrication;

[0026] Figure 5 This is a partial schematic diagram of a prefabricated ceramic matrix composite leaf crown structure after machining.

[0027] Figure 6 This is a schematic diagram of the yarn connection in the crown-blade structure of a ceramic matrix composite blade.

[0028] In the figure, the attached labels are as follows: leaf crown 1, upper margin plate 11, upper margin plate warp yarn 11a, upper margin plate weft yarn 11b, upper margin plate knotting yarn 11c, sealing comb teeth 12, sealing comb tooth warp yarn 12a, sealing comb tooth weft yarn 12b, serrated curved surface 13, leaf body 2, leaf body warp yarn 2a, leaf body weft yarn 2b, leaf body longitudinal section 20, leaf back curve 21, leaf basin curve 22, leaf body leading edge 23, leaf body trailing edge 24. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this application clearer, the application is described and illustrated below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application. All other embodiments obtained by those skilled in the art based on the embodiments provided in this application without inventive effort are within the scope of protection of this application.

[0030] Obviously, the accompanying drawings described below are merely some examples or embodiments of this application. Those skilled in the art can apply this application to other similar scenarios based on these drawings without any inventive effort. Furthermore, it is understood that although the efforts made in this development process may be complex and lengthy, for those skilled in the art related to the content disclosed in this application, any changes to design, manufacturing, or production based on the technical content disclosed in this application are merely conventional technical means and should not be construed as insufficient disclosure of the content of this application.

[0031] In this application, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application may be combined with other embodiments without conflict.

[0032] Unless otherwise defined, the technical or scientific terms used in this application shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms “a,” “an,” “a,” “the,” and similar words used in this application do not indicate quantity limitation and may indicate singular or plural. The terms “comprising,” “including,” “having,” and any variations thereof used 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 (elements) is not limited to the listed steps or units, but may also include steps or units not listed, or may include other steps or units inherent to these processes, methods, products, or devices. The terms “connected,” “linked,” “coupled,” and similar words used in this application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The terms “multiple” / “several” used in this application refer to two or more. “And / or” describes the relationship between related objects, indicating that three relationships may exist; for example, “A and / or B” can indicate: A alone, A and B simultaneously, or B alone. The character " / " generally indicates that the preceding and following objects are in an "or" relationship. The terms "first," "second," and "third" used in this application are merely to distinguish similar objects and do not represent a specific ordering of the objects.

[0033] This example uses the microstructure described in the invention to design a ceramic matrix composite blade crown-blade structure. The location of the blade crown-blade structure within the turbine rotor blade is as follows: Figure 1 As shown, the turbine comprises two parts: a crown 1 and a blade body 2. The crown is further divided into an upper edge plate 11 and sealing grates 12. The blade body 2 extends from near to far along the turbine radius, forming a perpendicular connection with the lower surface of the upper edge plate 11. The upper and lower surfaces of the upper edge plate 11 are irregular curved surfaces along the turbine circumference. The edges of the upper edge plates 11 of multiple circumferentially distributed blades contact each other to form the upper wall of the turbine airflow channel. The sealing grates 12 are located on the upper surface of the upper edge plate 11, extending circumferentially and approximately perpendicular to the leading and trailing edges of the blade body 2. They enhance the sealing effect, reduce axial leakage, and improve turbine efficiency.

[0034] The upper edge plate 11 of the blade crown has serrated curved surfaces 13 on both sides of its circumference, formed by machining. The interlocking of the curved surfaces 13 between adjacent upper edge plates 11 ensures that the contact surfaces remain pressed together during operation. Compared with a quadrilateral blade crown, this design has the advantages of increasing the blade vibration frequency and improving uneven wear on the contact surfaces. To reduce the centrifugal force and bending moment caused by the blade crown 1, the upper edge plate 11 adopts a variable cross-section design, with the cross-sectional thickness gradually decreasing from the blade body 2 towards the serrated curved surfaces 13, thus achieving weight reduction.

[0035] The longitudinal section 20 of the blade has an aerodynamic profile, consisting of two long curves and two short circular arcs. The blade basin curve 22 is the concave section of the profile, forming the pressure surface of the blade, while the blade back curve 21 is the convex section, forming the suction surface of the blade. The blade basin curve 22 and the blade back curve 21 are connected by two circular arcs, with the arc in the direction of incoming gas flow forming the leading edge 23 and the arc in the direction of outgoing gas flow forming the trailing edge 24.

[0036] In this example, the blade is woven using a 2.5D twill weave method. The warp yarns 2a are woven along a direction perpendicular to the longitudinal section 20 of the blade, while the weft yarns 2b are woven along a direction parallel to the longitudinal section 20. By aligning the warp yarns 2a perpendicular to the longitudinal section 20, the main direction of the yarns is kept as consistent as possible with the direction of stress on the blade, thus maximizing the material's performance.

[0037] The upper edge plate 11 of the leaf crown is woven using a three-dimensional orthogonal weaving method, with leaf warp yarns 2a drawn from above the leaf body 2 to participate in the weaving of the upper edge plate 11. Each row of leaf warp yarns 2a in the leaf body 2, after being drawn from above, is evenly divided into two groups (3 yarns in each group in this example) according to the directions of the leaf back curve 21 and the leaf base curve 22, and then merged to form two bundles of upper edge plate knotting yarns 11c to participate in the weaving of the upper edge plate 11. Figure 2 and Figure 6 As shown. Two bundles of upper edge plate knotted yarns 11c pass through the gap between the upper edge plate warp yarns 11a, forming an interlocking structure. Only half of the leaf body warp yarns 2a are drawn out to participate in the weaving of the upper edge plate 11; the remaining leaf body warp yarns 2a, which are on the same plane as the upper edge plate warp yarns 11a, only extend to the transition between the leaf body 2 and the upper edge plate 11, as shown. Figure 3 As shown.

[0038] The sealing grate warp yarns 12a originate from the outermost edge of the upper edge plate 11, and are drawn from the uppermost portion of the upper edge plate weft yarns 11b near the center of the blade crown 1, bending upwards and interlacing with the sealing grate weft yarns 12b to form two rows of tooth-like structures. The sealing grate weft yarns 12b extend along the turbine circumference, providing shape support and positioning for the sealing grate teeth 12, such as... Figure 5 As shown.

[0039] Different yarn densities and yarn plies can be used for each warp and weft yarn. Alternatively, yarn can be added or subtracted locally, or the number of layers can be increased or decreased locally. The mold is used to press and position the structural shape to form the structural outline.

[0040] To illustrate the effects of the present invention, the weaving parameters of the leaf crown-leaf body preform used in this embodiment are shown in Table 1.

[0041] Table 1. Weaving parameters of the crown-blade preform in this example.

[0042]

[0043] This example utilizes the microstructure described in the invention to ensure the continuity of fiber bundles between the leaf blade and the leaf crown; different weaving methods are used for the leaf blade and leaf crown according to load and shape characteristics, which improves the adaptability of materials and structure; the use of three-dimensional orthogonal weaving and yarn merging methods improves the connection strength between the leaf blade and the leaf crown.

[0044] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A ceramic matrix composite leaf crown-blade structure based on three-dimensional orthogonal weaving technology, comprising a leaf crown (1) and a blade (2), wherein the leaf crown (1) comprises an upper edge plate (11), the trailing edge of the blade (2) is connected to the leaf crown (1), the upper edge plate (11) comprises upper edge plate warp yarns (11a) and upper edge plate weft yarns (11b), the blade (2) comprises blade body warp yarns (2a) and blade body weft yarns (2b), wherein the upper edge plate warp yarns (11a) and upper edge plate weft yarns (11b) are interwoven, and the blade body warp yarns (2a) and blade body weft yarns (2b) are interwoven, characterized in that: The blade (2) is a structure with an aerodynamic profile, consisting of two long curves and two short arcs in its longitudinal section. The two long curves are the blade basin curve (22) and the blade back curve (21), and the two short arcs are the blade leading edge (23) and the blade trailing edge (24). The blade back curve (21) is a protruding section in the profile, forming the blade suction surface. The blade basin curve (22) is a concave section in the profile, forming the blade pressure surface. The ends of the blade basin curve (22) and the blade back curve (21) are connected by the blade leading edge (23) and the blade trailing edge (24), respectively. The short arc in the direction of gas flow is the blade leading edge (23), and the short arc in the direction of gas outflow is the blade trailing edge (24). At least part of the blade warp yarn (2a) in the blade (2) is drawn out from the end that mates with the upper edge plate (11) and follows the direction of the blade basin curve (22) and the blade back curve (21). The leaf blade is divided into two groups. The warp yarns (2a) of the same group are combined to form two bundles of upper edge plate knotting yarns (11c), which participate in the weaving of the upper edge plate (11). The upper edge plate knotting yarns (11c) pass through the gaps between the upper edge plate warp yarns (11a) and together with the upper edge plate warp yarns (11a) and upper edge plate weft yarns (11b) to perform three-dimensional orthogonal weaving, forming an interlocking structure. The leaf crown (1) includes sealing ferrules (12), which are located on the upper edge plate. On the upper surface of the edge plate (11), the sealing teeth (12) include sealing tooth warp yarns (12a) and sealing tooth weft yarns (12b). The sealing tooth warp yarns (12a) start from the outermost side of the upper edge plate (11), and are drawn out from the uppermost part of the upper edge plate weft yarns (11b) near the center of the leaf crown (1) and bent upward. The sealing tooth warp yarns (12a) are interwoven and wrapped between the sealing tooth weft yarns (12b) to form the sealing teeth (12).

2. The ceramic matrix composite blade-blade structure based on three-dimensional orthogonal weaving technology according to claim 1, characterized in that: The upper and lower surfaces of the upper edge plate (11) are irregular curved surfaces along the circumferential direction of the turbine where the blade (2) is located. The edges of multiple blade upper edge plates (11) distributed along the circumferential direction of the turbine contact each other to form the upper wall of the turbine airflow channel. The upper edge plate (11) extends along the circumferential direction of the turbine and is perpendicular or approximately perpendicular to the leading edge (23) of the blade.

3. The ceramic matrix composite blade-blade structure based on three-dimensional orthogonal weaving technology according to claim 2, characterized in that: The upper edge plate (11) has serrated curved surfaces (13) on both sides in the circumferential direction, and adjacent upper edge plates (11) mesh with each other through the serrated curved surfaces (13).

4. The ceramic matrix composite blade-blade structure based on three-dimensional orthogonal weaving technology according to claim 3, characterized in that: The thickness of the upper edge plate (11) gradually decreases from the connection between the blade (2) and the upper edge plate (11) toward the serrated curved surface (13).

5. The ceramic matrix composite blade-blade structure based on three-dimensional orthogonal weaving technology according to claim 4, characterized in that: The leaf body (2) is woven using a 2.5-dimensional twill weave method, wherein the warp yarn (2a) of the leaf body is woven in a direction perpendicular to the longitudinal section (20) of the leaf body, and the weft yarn (2b) of the leaf body is woven in a direction parallel to the longitudinal section (20) of the leaf body.

6. The ceramic matrix composite blade-blade structure based on three-dimensional orthogonal weaving technology according to claim 5, characterized in that: Only half of the leaf warp yarns (2a) are drawn out to participate in the weaving of the upper edge plate (11), while the remaining leaf warp yarns (2a) that are on the same plane as the upper edge plate warp yarns (11a) extend to the transition point between the leaf body (2) and the upper edge plate (11) and are cut off.

7. The ceramic matrix composite blade-blade structure based on three-dimensional orthogonal weaving technology according to claim 1, characterized in that: The upper edge plate warp yarn (11a), upper edge plate weft yarn (11b), leaf body warp yarn (2a), and leaf body weft yarn (2b) are all made of ceramic matrix composite material.

8. The ceramic matrix composite blade-blade structure based on three-dimensional orthogonal weaving technology according to claim 1, characterized in that: The leaf crown (1) is provided with two sealing grates (12), which are arranged parallel to each other.

9. The ceramic matrix composite blade-blade structure based on three-dimensional orthogonal weaving technology according to claim 1, characterized in that: Both the closed-tooth warp yarn (12a) and the closed-tooth weft yarn (12b) are made of ceramic matrix composite material.

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