Manufacturing method of blade rear edge bonding structure, fan blade and wind turbine generator

Abstract

The embodiment of the invention provides a manufacturing method of a blade rear edge bonding structure, a fan blade and a wind turbine generator, and belongs to the technical field of blade preparation. The method comprises the steps that the bonding thickness and the bonding width of each bonding area of the blade rear edge are determined; baffles are arranged at the two ends of each bonding area respectively, forming tools are installed on the bonding areas based on the bonding thickness and the bonding width, and the blades, the baffles and the forming tools form a containing cavity; laying a plurality of prepreg layers and a foaming material in the accommodating cavity, wherein the amount of the foaming material is determined by the volume of the accommodating cavity; and heating each bonding area until the curing degree of the foaming material reaches a preset threshold value, stopping heating, and completing preparation of the blade rear edge bonding structure. The method has the advantages of high positioning precision, simple forming method, high forming quality, and high structural rigidity and buckling stability of the integral trailing edge of the blade.

Description

Technical Field

[0001] The present invention relates to the technical field of blade preparation, and in particular to a method for manufacturing a blade trailing edge bonding structure, a wind turbine blade and a wind turbine generator set. Background Art

[0002] In a wind turbine, wind turbine blades are important devices that convert wind energy into electrical energy. At present, in order to obtain high efficiency, good performance and excellent economy, wind turbines are developing in the direction of being larger, lighter and more reliable. As a key component of a wind turbine that converts wind energy into electrical energy, the performance of wind turbine blades is directly related to the entire wind power generation system. Therefore, the reliability of the blades is particularly important for the power generation efficiency of the system. However, since wind turbine blades are mostly made of composite materials, especially large-sized offshore blades, their shapes and structures are relatively complex, and they are subjected to harsh and complex dynamic loads during operation. Among blade accidents, accidents caused by damage caused by cracking of the trailing edge of the blade account for a large proportion. In addition, under the repeated action of wind load fatigue, the trailing edge area is greatly deformed and is also prone to damage. Therefore, in order to improve the trailing edge stability of wind turbine blades, the design of the trailing edge area, especially the trailing edge bonding area, is a key area of ​​blade design and technology, and special attention needs to be paid. At present, the trailing edge of the blade is usually bonded by using a bonding angle at about 20m in the trailing edge area, and PVC wrapping cloth is generally used for bonding after 20 meters, while direct bonding is generally used for bonding near the tip section. It is necessary to prepare the bonding angle and PVC wrapping cloth. Due to the complex shape and special position, infusion defects are prone to occur, resulting in unnecessary time consumption such as quality and rework and repair. Moreover, with the development of large-scale blades and the requirements of cost reduction and efficiency improvement, the blade design is longer, lighter, and more flexible. The trailing edge, especially the maximum chord length and the root area of ​​the blade are obviously deformed under load, which is not conducive to ensuring the operating stability of large blades.

[0003] In the prior art, patent CN115795708A discloses a method and device for simulating the mold shape of the trailing edge bonding angle of a wind turbine blade using three-dimensional software. This method mainly uses a three-dimensional method to quickly simulate the mold shape of the trailing edge bonding angle to achieve accurate bonding of the bonding angle and ensure the quality of the finished wind turbine blade. The main purpose is to make a bonding angle mold. It does not involve a specific design and method for trailing edge bonding. Patent CN209141488U discloses a wind turbine blade trailing edge bonding angle forming device, which mainly uses a core material block as a mold at the bonding position to form the adhesive angle and bond. This method has a complex shape of the trailing edge of the blade and poor conformability of the core material, resulting in low molding quality. And it only involves a molding device, and the specific molding preparation method is not involved. Patent CN215762026U discloses a trailing edge structure of a wind turbine blade and a wind turbine blade, which mainly introduces a sandwich structure with a core added at the trailing edge to meet the trailing edge bonding and buckling requirements. This method also only involves the structural form, and the existing molding technology still has shortcomings such as low molding quality and difficult to control shape and size, which cannot meet the high-reliability bonding requirements of the blade.

[0004] Therefore, developing a trailing edge bonding form and method that is simple to construct, has guaranteed quality, and can overall improve the trailing edge stiffness of the blade is of great significance for the safety and reliability of large blades. Summary of the invention

[0005] The purpose of the embodiments of the present invention is to provide a method for manufacturing a blade trailing edge bonding structure, a wind turbine blade and a wind turbine generator set, so as to solve the above-mentioned problems of complex manufacturing, high molding defects, low trailing edge stiffness and low reliability.

[0006] In order to achieve the above object, an embodiment of the present invention provides a method for manufacturing a blade trailing edge bonding structure, the method comprising: Determine the bonding thickness and bonding width of each bonding area at the trailing edge of the blade; Baffles are respectively arranged at both ends of each bonding area, and based on the bonding thickness and bonding width, a molding tool is installed on the bonding area, and the blades, the baffles and the installed molding tool form a receiving cavity; Laying multiple layers of prepreg layers and foaming material in the accommodation cavity, wherein the amount of the foaming material is determined by the volume of the accommodation cavity; Each bonding area is heated until the curing degree of the foaming material reaches a preset threshold, and the heating is stopped to complete the preparation of the blade trailing edge bonding structure.

[0007] Optionally, determining a bonding thickness and a bonding width of a blade trailing edge bonding area includes: According to the blade design data, the trailing edge simulation of the blade layer is carried out; Based on the finite element analysis method, the buckling stability corresponding to different bonding thicknesses and bonding widths is calculated; The bonding thickness and bonding width corresponding to the highest buckling stability are determined as the final bonding thickness and bonding width of the blade trailing edge bonding area.

[0008] Optionally, the molding tool comprises: A first support frame is vertically arranged on the blade mold; At least one connecting crossbar, movably disposed on the first support frame, capable of generating a vertical displacement relative to the first support frame; A second support plate is movably arranged on the corresponding connecting cross bar, capable of generating vertical displacement and lateral displacement relative to the connecting cross bar, wherein the bottom end of the second support plate contacts the surface of the blade; At least two telescopic adjustment rods are rotatably arranged on corresponding connecting cross rods, and ends of the telescopic adjustment rods are connected to the upper baffle.

[0009] Optionally, a suction cup is provided at the end of the telescopic adjustment rod, and the telescopic adjustment rod is connected to the upper baffle via the suction cup.

[0010] Optionally, the first support frame, the connecting cross bar and the second support plate are each provided with a plurality of positioning holes, and the positions of the connecting cross bar and the second support plate are fixed by inserting positioning pins into corresponding positioning holes.

[0011] Optionally, the baffle is a foam board.

[0012] Optionally, the prepreg layer is a biaxial or triaxial epoxy resin-based prepreg.

[0013] Optionally, the foaming material is a fiber-reinforced foaming core material.

[0014] On the other hand, an embodiment of the present invention further provides a fan blade, which is manufactured using the above-mentioned method for manufacturing the blade trailing edge bonding structure.

[0015] On the other hand, an embodiment of the present invention further provides a wind turbine generator set, comprising the above-mentioned wind turbine blades.

[0016] The manufacturing method of the blade trailing edge bonding structure of the technical solution has high positioning accuracy, simple molding method, high molding quality, and high rigidity and buckling stability of the overall blade trailing edge structure.

[0017] Other features and advantages of the embodiments of the present invention will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following specific implementations, they are used to explain the embodiments of the present invention, but do not constitute a limitation on the embodiments of the present invention. In the accompanying drawings: Figure 1 It is a flow chart of a method for manufacturing a blade trailing edge bonding structure provided by the present invention; Figure 2 is a schematic diagram of the trailing edge bonding shape provided by the present invention; Figure 3 is a schematic diagram of the trailing edge after filling provided by the present invention; Figure 4 It is a structural schematic diagram of the forming tooling provided by the present invention.

[0019] Description of Reference Numerals 11-first support frame; 12-connecting cross bar; 13-second support plate; 14- telescopic adjustment rod; 15- upper baffle; 16- suction cup; 2-blade mold; 3-blade; 101-positioning hole. DETAILED DESCRIPTION

[0020] The specific implementation of the embodiment of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the embodiment of the present invention, and is not used to limit the embodiment of the present invention.

[0021] In the embodiments of the present invention, unless otherwise specified, directional words such as "up, down, left, right" generally refer to the directions or positional relationships shown in the accompanying drawings, or the directions or positional relationships in which the inventive product is usually placed when in use.

[0022] The terms “first”, “second”, “third”, etc. are merely used for distinguishing descriptions and should not be understood as indicating or implying relative importance.

[0023] The terms "parallel", "vertical", etc. do not mean that the components must be absolutely parallel or vertical, but can be slightly tilted. For example, "parallel" only means that its direction is more parallel than "vertical", and does not mean that the structure must be completely parallel, but can be slightly tilted.

[0024] The terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal, vertical or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0025] In addition, the terms "roughly" and "basically" are intended to explain that the relevant content does not require absolute precision, but can have certain deviations. For example, "roughly equal" does not only mean absolute equality. Since it is difficult to achieve absolute "equality" in actual production and operation, there are generally certain deviations. Therefore, in addition to absolute equality, "roughly equal" also includes the above-mentioned situation with certain deviations. Taking this as an example, in other cases, unless otherwise specified, the terms "roughly" and "basically" have similar meanings to the above.

[0026] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] Figure 1 It is a flow chart of a method for manufacturing a blade trailing edge bonding structure provided by the present invention; Figure 2 is a schematic diagram of the trailing edge bonding shape provided by the present invention; Figure 3 is a schematic diagram of the trailing edge after filling provided by the present invention; Figure 4 It is a structural schematic diagram of the forming tooling provided by the present invention.

[0028] like Figure 1-3 As shown, this embodiment provides a method for manufacturing a blade trailing edge bonding structure, the method comprising: Determine the bonding thickness and bonding width of each bonding area at the trailing edge of the blade; Baffles are respectively arranged at both ends of each bonding area, and based on the bonding thickness and bonding width, a molding tool is installed on the bonding area, and the blades, the baffles and the installed molding tool form a receiving cavity; Laying multiple layers of prepreg layers and foaming material in the accommodation cavity, wherein the amount of the foaming material is determined by the volume of the accommodation cavity; Each bonding area is heated until the curing degree of the foaming material reaches a preset threshold, and the heating is stopped to complete the preparation of the blade trailing edge bonding structure.

[0029] Specifically, in this embodiment, the installation of the molding tool can adjust the bonding thickness and bonding width of the bonding area; the heating temperature for heating each bonding area can be determined according to the type of foaming material. After the preparation of the blade trailing edge bonding structure is completed, the molding tool is removed, and the blade is further coated with glue and molded to complete the bonding of the blade.

[0030] Further, determining the bonding thickness and bonding width of the blade trailing edge bonding area includes: According to the blade design data, the trailing edge simulation of the blade layer is carried out; Based on the finite element analysis method, the buckling stability corresponding to different bonding thicknesses and bonding widths is calculated; The bonding thickness and bonding width corresponding to the highest buckling stability are determined as the final bonding thickness and bonding width of the blade trailing edge bonding area.

[0031] Specifically, in this embodiment, three-dimensional software is used to simulate the trailing edge of the ply to simulate the conformal bonding shape such as the appropriate bonding thickness and width of the trailing edge of the blade from the bonding angle of the trailing edge of the blade to the mold seam, and then the bonding surface of the trailing edge bonding molding tooling is prepared according to the simulated data. During the simulation process, based on the finite element analysis method, the buckling stability corresponding to different bonding thicknesses and bonding widths is calculated, and the bonding thickness and bonding width corresponding to the highest buckling stability are determined as the final bonding thickness and bonding width of the trailing edge bonding area of ​​the blade.

[0032] Furthermore, if Figure 4 The molding tool shown includes: A first support frame 11 is vertically arranged on the blade mold 2; At least one connecting cross bar 12 is movably disposed on the first support frame 11 and can generate vertical displacement relative to the first support frame 11; The second support plate 13 is movably arranged on the corresponding connecting cross bar 12, and can generate vertical displacement and lateral displacement relative to the connecting cross bar 12, and the bottom end of the second support plate 13 is in contact with the surface of the blade 3; At least two telescopic adjustment rods 14 are rotatably disposed on the corresponding first support frame 11 and the connecting cross bar 12 , respectively, and the ends of the telescopic adjustment rods 14 are connected to the upper baffle 15 .

[0033] Specifically, in this embodiment, the first support frame 11 is fixed on the blade mold 2, the connecting cross bar 12 is movably set on the first support frame 11, and the second support plate 13 is movably set on the connecting cross bar 12, so as to realize the adjustment of the width of the accommodating cavity; after the prepreg layer and the foaming material are laid in the accommodating cavity, by adjusting the length and angle of the two retractable adjustment rods 14, the upper baffle 15 is at a specified height, so that the accommodating cavity constitutes a closed area.

[0034] In addition, in order to ensure the stability of the contact part, a slide rail is vertically arranged on the first support frame 11, and the connecting cross bar 12 is slidably arranged on the slide rail of the first support frame 11 by a slider to limit the movement path of the connecting cross bar 12, so that the connecting cross bar 12 can achieve vertical movement along the slide rail; similarly, a slide rail is arranged on the connecting cross bar 12, and the second support plate 13 is slidably arranged on the slide rail of the connecting cross bar by a slider to achieve lateral movement of the second support plate 13. At the same time, in order to achieve vertical movement of the second support plate 13, the second support plate 13 is installed on the slider by screws, and the height of the second support plate 13 relative to the slider is adjusted according to usage requirements.

[0035] Furthermore, a suction cup 16 is provided at the end of the telescopic adjustment rod 14 , and the telescopic adjustment rod 14 is connected to the upper baffle 15 via the suction cup 16 .

[0036] Specifically, in this embodiment, in order to facilitate installation and disassembly, as well as adjustment of the connection position, a suction cup 16 is provided at the end of the telescopic adjustment rod 14 , and is connected to the upper baffle 15 via the suction cup 16 .

[0037] Furthermore, a plurality of positioning holes 101 are provided on the first support frame 11 , the connecting cross bar 12 and the second support plate 13 , and the positions of the connecting cross bar 12 and the second support plate 13 are fixed by inserting the positioning pins 1 into the corresponding positioning holes 101 .

[0038] Specifically, in this embodiment, the first support frame 11 is fixed to the blade mold 2 (female mold) by the locking mechanism 1, and the first support frame 11 is provided with a plurality of positioning holes 101 from top to bottom. At the same time, a plurality of positioning holes 101 are also provided on the connecting cross bar 12. When it is necessary to adjust the height between the connecting cross bar 12 and the first support frame 11, the latch on the first support frame 11 is pulled out, the connecting cross bar 12 is moved to the corresponding position, and the latch is inserted into the corresponding two positioning holes 101 to achieve the fixation between the connecting cross bar 12 and the first support frame 11. When it is necessary to adjust the width between the connecting cross bar 12 and the second support plate 13, the latch on the second support plate 13 is pulled out, the position of the second support plate 13 is adjusted to the corresponding position, and the latch is inserted into the corresponding two positioning holes 101 to achieve the fixation between the connecting cross bar 12 and the second support plate 13. The second support plate 13 has a certain width and length, which is determined by bonding parameters such as bonding width.

[0039] Furthermore, the baffle is a foam board. The foam board is used as the side board for limiting and blocking, which is light in weight and low in use cost.

[0040] Furthermore, the prepreg layer is a biaxial or triaxial epoxy resin-based prepreg.

[0041] Furthermore, the foaming material adopts a fiber-reinforced foaming core material, which has stable performance and good foaming effect.

[0042] This embodiment also provides a fan blade, which is manufactured using the above-mentioned method for manufacturing the blade trailing edge bonding structure.

[0043] This embodiment also provides a wind turbine generator set, comprising the above-mentioned wind turbine blades.

[0044] Example 1 Preparation of integral forming tooling. The trailing edge of the ply is simulated by 3D software to simulate the appropriate bonding thickness and width of the trailing edge of the blade and the conformal bonding shape. Then, the finite element results are comprehensively considered and the trailing edge bonding forming tooling is prepared according to the simulated data.

[0045] After the preparation of the molding tooling is completed. After the blade is formed, tear off the vacuum bag and auxiliary materials such as the demoulding cloth at the bonding point of the trailing edge, clean them up, and then lay 8 layers of biaxial cloth epoxy resin prepreg along the bottom and trailing edge of the blade shell, the upper rib and the rib in the blade cavity, with a laying angle of ±45 degrees; set the molding tooling along the axial direction of the blade root from 2m to 12m, and close the openings on both sides of the 2m blade root and 12m with foam baffles. Then, use a medium-ratio adhesive film (3-5 times the foaming rate) on the prepreg, with an original density of 0.6g / cm 3 , density after foaming 0.12g / cm 3 According to the calculated foaming volume, it is calculated that a certain amount of about 120kg of self-foaming core board needs to be laid. The trailing edge is closed as a whole with a retaining edge close to the side of the cavity. The mold is heated to 80-90 degrees, and the foam film is further foamed according to the shape of the mold, and forms an integral sandwich structure with the surrounding epoxy resin prepreg. Then, the 12m-blade tip section is laid and heated in sequence, and the sections are laid every 10m, heated and foamed, and then the heating is stopped after the overall heating reaches a certain degree of curing; then, the adhesive is further applied to the formed bonding area to perform blade mold bonding. Finite element calculation of buckling stability can be improved by 8%.

[0046] Example 2 The preparation of the integral forming tooling is to simulate the trailing edge of the ply through 3D software to simulate the appropriate bonding thickness and width of the trailing edge of the blade as well as the conformal bonding shape. Then, the finite element results are comprehensively considered and the trailing edge bonding forming tooling is prepared according to the simulated data.

[0047] After the preparation of the molding tooling is completed. After the blade is formed, tear off the vacuum bag and auxiliary materials such as the demoulding cloth at the bonding point of the trailing edge, clean them up, and then lay 6 layers of triaxial cloth epoxy resin prepreg along the bottom and trailing edge of the blade shell, the upper rib and the rib on the right side away from the cavity, with a laying angle of ±45 / 0 degrees; set the molding tooling along the axial direction of the blade root from 2m to 22m, and close the openings on both sides of the 2m blade root and 22m with foam baffles. Use low-ratio adhesive film (2-4 times foaming rate) with an original density of 1.6g / cm 3 , density after foaming 0.3g / cm 3 According to the calculated foaming volume, it is calculated that a certain amount of about 60kg of self-foaming core material board needs to be laid. Then, on the prepreg, a certain amount of epoxy resin foam is cast and laid according to the calculated foaming volume. The mold is heated to 100-150 degrees, and the epoxy foam is further foamed according to the shape of the mold, and forms an integral sandwich structure with the surrounding epoxy resin prepreg. Then, the 22m-blade tip section is laid and heated in sequence, and the sections are laid every 20m, heated and foamed, and then the heating can be stopped after the whole is heated to a certain degree of curing; then, the adhesive is further applied to the molded bonding area to perform blade mold bonding. Finite element calculation of buckling stability can be improved by 10%.

[0048] The optional implementation modes of the embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details in the above implementation modes. Within the technical concept of the embodiments of the present invention, various simple modifications can be made to the technical scheme of the embodiments of the present invention, and these simple modifications all belong to the protection scope of the embodiments of the present invention.

[0049] Those skilled in the art can understand that all or part of the steps in the above-mentioned embodiment method can be completed by instructing the relevant hardware through a program, and the program is stored in a storage medium, including several instructions for making a single-chip microcomputer, a chip or a processor (processor) perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0050] The optional embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details in the above embodiments. Within the technical concept of the embodiments of the present invention, the technical scheme of the embodiments of the present invention can be subjected to a variety of simple modifications, and these simple modifications all belong to the protection scope of the embodiments of the present invention. It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner when there is no contradiction. In order to avoid unnecessary repetition, the embodiments of the present invention will not further describe various possible combinations. In addition, various implementations of the embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the embodiments of the present invention, they should also be regarded as the contents disclosed in the embodiments of the present invention.

Claims

1. A method for manufacturing a blade trailing edge bonding structure, characterized in that: The method comprises: Determine the bonding thickness and bonding width of each bonding area at the trailing edge of the blade; Baffles are respectively arranged at both ends of each bonding area, and based on the bonding thickness and bonding width, a molding tool is installed on the bonding area, and the blades, the baffles and the installed molding tool form a receiving cavity; Laying multiple layers of prepreg layers and foaming material in the accommodation cavity, wherein the amount of the foaming material is determined by the volume of the accommodation cavity; Each bonding area is heated until the curing degree of the foaming material reaches a preset threshold, and the heating is stopped to complete the preparation of the blade trailing edge bonding structure.

2. The method for manufacturing a blade trailing edge bonding structure according to claim 1, characterized in that: Determine the bond thickness and bond width of the blade trailing edge bond area, including: According to the blade design data, the trailing edge simulation of the blade layer is carried out; Based on the finite element analysis method, the buckling stability corresponding to different bonding thicknesses and bonding widths is calculated; The bonding thickness and bonding width corresponding to the highest buckling stability are determined as the final bonding thickness and bonding width of the blade trailing edge bonding area.

3. The method for manufacturing a blade trailing edge bonding structure according to claim 1, characterized in that: The molding tool comprises: A first support frame is vertically arranged on the blade mold; At least one connecting crossbar, movably disposed on the first support frame, capable of generating a vertical displacement relative to the first support frame; A second support plate is movably arranged on the corresponding connecting cross bar, capable of generating vertical displacement and lateral displacement relative to the connecting cross bar, wherein the bottom end of the second support plate contacts the surface of the blade; At least two telescopic adjustment rods are rotatably arranged on corresponding connecting cross rods, and ends of the telescopic adjustment rods are connected to the upper baffle.

4. The method for manufacturing a blade trailing edge bonding structure according to claim 3, characterized in that: A suction cup is arranged at the end of the telescopic adjustment rod, and the telescopic adjustment rod is connected to the upper baffle through the suction cup.

5. The method for manufacturing a blade trailing edge bonding structure according to claim 3, characterized in that: The first support frame, the connecting cross bar and the second support plate are all provided with a plurality of positioning holes, and the positions of the connecting cross bar and the second support plate are fixed by inserting positioning pins into corresponding positioning holes.

6. The method for manufacturing a blade trailing edge bonding structure according to claim 1, characterized in that: The baffle is a foam board.

7. The method for manufacturing a blade trailing edge bonding structure according to claim 1, characterized in that: The prepreg layer is a biaxial or triaxial epoxy resin-based prepreg.

8. The method for manufacturing a blade trailing edge bonding structure according to claim 1, characterized in that: The foaming material is a fiber-reinforced foaming core material.

9. A fan blade, characterized in that: The blade trailing edge bonding structure is manufactured by the manufacturing method of any one of claims 1 to 8.

10. A wind turbine generator set, characterized in that: Including the fan blade described in claim 9.

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