Sandwich structure, manufacturing method thereof, fan blade and wind generating set

Abstract

The invention provides a sandwich structure, a manufacturing method thereof, a fan blade and a wind generating set. The sandwich structure comprises: a core material layer; the gridding cloth layer comprises an upper gridding cloth layer and a lower gridding cloth layer, the upper gridding cloth layer is arranged on the upper surface of the core material layer and provided with first gridding holes, and the lower gridding cloth layer is arranged on the lower surface of the core material layer and provided with second gridding holes; the fiber fabric layer comprises an upper fiber fabric layer arranged on the upper surface of the upper gridding cloth layer and a lower fiber fabric layer arranged on the lower surface of the lower gridding cloth layer; the resin, the core material layer, the gridding cloth layer and the fiber fabric layer are formed in a composite mode, and resin blocks are formed in at least one part of the first gridding holes and at least one part of the second gridding holes. According to the invention, the interface performance can be improved, the consistency of the interface performance can be ensured, and the overall strength of the sandwich structure can be ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of wind power generation, and in particular to a sandwich structure, a manufacturing method thereof, a wind turbine blade and a wind power generator set. Background Art

[0002] Core material is one of the key materials for wind turbine blade manufacturing. Currently, the core materials used in wind turbine blade manufacturing mainly include balsa wood and rigid foam.

[0003] The core material is often used in the shell and web of the blade. Generally, a sandwich structure is adopted to increase the structural rigidity, prevent local instability, and improve the load-bearing capacity of the entire blade. At the same time, the lower density helps the blade develop in the direction of lightweight and larger size.

[0004] At present, the sandwich structure is formed by laying fiber fabrics on both sides of the core material and connecting them into a whole by using a resin integral infusion molding process. However, the sandwich structure in the prior art has the problem that the core material and the fiber fabric are easily peeled off. Summary of the invention

[0005] An object of the present invention is to provide a sandwich structure capable of improving the peel strength of the sandwich structure, a manufacturing method thereof, a wind turbine blade and a wind turbine generator set.

[0006] Another object of the present invention is to provide a sandwich structure capable of improving the peel strength of the sandwich structure while preventing the core material from breaking or falling apart, a manufacturing method thereof, a wind turbine blade and a wind turbine generator set.

[0007] Another object of the present invention is to provide a sandwich structure capable of reducing the manufacturing cost of the sandwich structure, a manufacturing method thereof, a wind turbine blade and a wind turbine generator set.

[0008] Another object of the present invention is to simplify the method for manufacturing the sandwich structure.

[0009] According to one aspect of the present invention, there is provided a sandwich structure of a wind turbine blade, the sandwich structure comprising: a core material layer; a mesh cloth layer, comprising an upper mesh cloth layer provided on the upper surface of the core material layer and having first mesh holes, and a lower mesh cloth layer provided on the lower surface of the core material layer and having second mesh holes; a fiber fabric layer, comprising an upper fiber fabric layer provided on the upper surface of the upper mesh cloth layer, and a lower fiber fabric layer provided on the lower surface of the lower mesh cloth layer; and a resin, which is compositely molded with the core material layer, the mesh cloth layer and the fiber fabric layer, and forms a resin block in at least a portion of the first mesh holes and at least a portion of the second mesh holes.

[0010] Optionally, the upper mesh cloth layer and the upper fiber fabric layer are woven together, and / or the lower mesh cloth layer and the lower fiber fabric layer are woven together.

[0011] Optionally, a plurality of grooves are formed in the core material layer, the plurality of grooves extend a predetermined distance from the upper surface of the core material layer toward the lower surface of the core material layer and are separated from the lower surface of the core material layer, and the resin fills at least a portion of the plurality of grooves.

[0012] Optionally, the upper mesh cloth layer includes cross-woven first warp yarns and first weft yarns, the first warp yarns and the first weft yarns form the first mesh holes, and the lower mesh cloth layer includes cross-woven second warp yarns and second weft yarns, the second warp yarns and the second weft yarns form the second mesh holes.

[0013] Optionally, the first warp yarn is woven orthogonally to the first weft yarn and the first warp yarn surrounds the first weft yarn, and the second warp yarn is woven orthogonally to the second weft yarn and the second warp yarn surrounds the second weft yarn.

[0014] Optionally, the area of ​​the second mesh holes is smaller than the area of ​​the first mesh holes.

[0015] Optionally, the weight of the upper mesh fabric layer and the lower mesh fabric layer is 50 g / m 2 -200g / m 2 The area of ​​the first mesh hole and the second mesh hole is 2 mm 2 -9mm 2 .

[0016] Optionally, the grammage of the mesh cloth layer is less than the grammage of the fiber fabric layer.

[0017] Optionally, the upper mesh cloth layer and the lower mesh cloth layer are both configured as a single layer.

[0018] Optionally, the upper mesh cloth layer and the lower mesh cloth layer are glass fiber or carbon fiber.

[0019] Optionally, the plurality of grooves are formed along two directions orthogonal to each other, the core material layer is further provided with a plurality of through holes, the plurality of through holes penetrate the core material layer, and the resin fills at least a portion of the through holes.

[0020] Optionally, the core material layer includes polyvinyl chloride foam, polyethylene terephthalate foam, high-performance high-chlorinated polyethylene foam, polyurethane foam, polystyrene foam, polyethylene foam, polymethacrylimide foam, polyamide foam, polyimide foam, polyarylethernitrile foam, natural fiber foam, balsa wood, paulownia wood or a composite of at least two of them, and / or the fiber fabric layer includes glass fiber, carbon fiber, basalt fiber, aramid fiber, natural fiber, ultra-high molecular polyethylene fiber or a blended fabric of at least two of them, and / or the resin is a thermoplastic resin or a thermosetting resin.

[0021] According to another aspect of the present invention, there is provided a method for manufacturing a sandwich structure of a wind turbine blade, the manufacturing method comprising: forming a stacked body, the stacked body comprising a core material layer, a mesh cloth layer and a fiber fabric layer, the mesh cloth layer comprising an upper mesh cloth layer arranged on the upper surface of the core material layer and having a first mesh hole, and a lower mesh cloth layer arranged on the lower surface of the core material layer and having a second mesh hole, the fiber fabric layer comprising an upper fiber fabric layer arranged on the upper surface of the upper mesh cloth layer and a lower fiber fabric layer arranged on the lower surface of the lower mesh cloth layer; pouring resin into the stacked body and curing the resin so that the resin is compositely molded with the core material layer, the mesh cloth layer and the fiber fabric layer, and the resin forms a resin block in at least a portion of the first mesh hole and at least a portion of the second mesh hole.

[0022] Optionally, the steps of forming the stacking body include: bonding the lower mesh cloth layer to the lower surface of the core material layer; cutting the core material layer to form a plurality of grooves, wherein the plurality of grooves extend from the upper surface of the core material layer toward the lower surface of the core material layer by a predetermined distance and are separated from the lower surface of the core material layer; laying the lower fiber fabric layer and the core material layer bonded with the lower mesh cloth layer on the mold in sequence; and weaving the upper mesh cloth layer and the upper fiber fabric layer together and laying them on the upper surface of the core material layer.

[0023] Optionally, the step of forming the stacking body includes: cutting the core material layer to form a plurality of grooves, wherein the plurality of grooves extend from the upper surface of the core material layer toward the lower surface of the core material layer by a predetermined distance and are separated from the lower surface of the core material layer; weaving the lower fiber fabric layer and the lower mesh cloth layer together and laying them on a mold, wherein the lower mesh cloth layer is located on the lower fiber fabric layer; laying the core material layer on the lower mesh cloth layer; and weaving the upper mesh cloth layer and the upper fiber fabric layer together and laying them on the upper surface of the core material layer.

[0024] According to another aspect of the present invention, a wind blade is provided, wherein the wind blade comprises the sandwich structure of the wind blade as described above.

[0025] Optionally, the sandwich structure constitutes at least a part of at least one of a web and a blade shell of the wind blade.

[0026] According to another aspect of the present invention, a wind turbine generator set is provided, wherein the wind turbine generator set comprises the wind turbine blade as described above.

[0027] According to the present invention, mesh cloth layers are provided on both sides of the core material layer, which can improve the interface performance of both sides and ensure the consistency of the interface performance of both sides, thereby improving the peeling strength of both sides, which is more conducive to ensuring the overall strength of the sandwich structure.

[0028] According to the present invention, the mesh cloth layer and the fiber fabric layer can be woven together in advance and laid together with the fiber fabric layer without increasing the number of steps.

[0029] According to the present invention, the support strength and the peeling strength can be improved at the same time by adjusting the area of ​​the second mesh holes and the area of ​​the first mesh holes. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description in conjunction with the accompanying drawings, in which:

[0031] Figure 1 is an exploded schematic diagram of a sandwich structure according to an embodiment of the present invention;

[0032] Figure 2 is a perspective view of a sandwich structure according to an embodiment of the present invention, a portion of the sandwich structure being cut away;

[0033] Figure 3 is a schematic diagram of a mesh fabric layer used in a sandwich structure according to an embodiment of the present invention;

[0034] Figure 4 is a flow chart of a method for manufacturing a sandwich structure according to an embodiment of the present invention;

[0035] Figure 5 is a flow chart of a method for forming a stack according to one embodiment of the present invention;

[0036] Figure 6 is a flow chart of a method for forming a stack according to another embodiment of the present invention.

[0037] Explanation of the symbols in the drawings: 100 - sandwich structure, 10 - core material layer, 11 - groove, 20 - mesh cloth layer, 21 - upper mesh cloth layer, 21a - first mesh hole, 21b - first warp yarn, 21c - first weft yarn, 22 - lower mesh cloth layer, 30 - fiber fabric layer, 31 - upper fiber fabric layer, 32 - lower fiber fabric layer. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0040] Sandwich structure

[0041] Below, we will refer to Figures 1 to 3 A sandwich structure according to an embodiment of the present invention is described. Figure 1 is an exploded schematic diagram of a sandwich structure according to an embodiment of the present invention; Figure 2 is a perspective view of a sandwich structure according to an embodiment of the present invention, a portion of the sandwich structure being cut away; Figure 3 is a schematic diagram of a mesh fabric layer used in a sandwich structure according to an embodiment of the present invention.

[0042] like Figures 1 to 3 As shown, the sandwich structure of the wind turbine blade according to the embodiment of the present invention may include a core material layer 10 , a mesh cloth layer 20 , a fiber fabric layer 30 , and a resin compositely molded with the core material layer 10 , the mesh cloth layer 20 and the fiber fabric layer 30 .

[0043] The mesh cloth layer 20 may include an upper mesh cloth layer 21 disposed on the upper surface of the core material layer 10 and a lower mesh cloth layer 22 disposed on the lower surface of the core material layer 10. The fiber fabric layer 30 may include an upper fiber fabric layer 31 disposed on the upper surface of the upper mesh cloth layer 21 and a lower fiber fabric layer 32 disposed on the lower surface of the lower mesh cloth layer 22.

[0044] According to an embodiment of the present invention, the upper mesh cloth layer 21 has first mesh holes 21a, the lower mesh cloth layer 22 has second mesh holes (not shown), and the resin can form a resin block in at least a portion of the first mesh holes 21a and at least a portion of the second mesh holes.

[0045] The present invention forms an upper mesh cloth layer 21 having first mesh holes 21a between the core material layer 10 and the upper fiber fabric layer 31, and forms a lower mesh cloth layer 22 having second mesh holes between the core material layer 10 and the lower fiber fabric layer 32. When the core material layer 10, the mesh cloth layer 20 and the fiber fabric layer 30 are infused with resin and compositely molded with the core material layer 10, the mesh cloth layer 20 and the fiber fabric layer 30, the resin can form resin blocks in at least a portion of the first mesh holes 21a and at least a portion of the second mesh holes, thereby increasing the contact area between the core material layer 10 and the fiber fabric layer 30, improving the interface performance, and thus improving the peeling strength.

[0046] According to the present invention, the mesh cloth is cheap and can be integrally formed with the core material layer and the fiber fabric layer during the resin infusion process of manufacturing the sandwich structure, so there is no need to introduce a separate manufacturing process. Compared with the case where a prepreg is provided between the core material layer and the fiber fabric layer, cost can be saved and the manufacturing process can be simplified. In addition, compared with the case where an adhesive film is provided between the core material layer and the fiber fabric layer, cost can be saved and there is no need to perform a process of hot pressing the adhesive film.

[0047] In addition, the present invention arranges mesh cloth layers on both sides of the core material layer, which can improve the interface performance of both sides and ensure the consistency of the interface performance of both sides, thereby improving the peeling strength of both sides, which is more conducive to ensuring the overall strength of the sandwich structure.

[0048] Hereinafter, the specific structure of the sandwich structure according to the embodiment of the present invention will be described in detail.

[0049] According to an embodiment of the present invention, the core material layer 10 may include polyvinyl chloride (PVC) foam, polyethylene terephthalate (PET) foam, high-performance high-chlorinated polyethylene (HPE) foam, polyurethane (PU) foam, polystyrene (PS) foam, polyethylene (PE) foam, polymethacrylimide (PMI) foam, polyamide (PA) foam, polyimide (PI) foam, polyarylethernitrile (PEN) foam, natural fiber foam, balsa wood, paulownia wood, or a composite of at least two of them. However, the present invention does not specifically limit the specific material of the core material layer 10.

[0050] According to an embodiment of the present invention, the fiber fabric layer 30 may include glass fiber, carbon fiber, basalt fiber, aramid fiber, natural fiber, ultra-high molecular weight polyethylene fiber, or a blended fabric of at least two of them. However, the present invention does not specifically limit the specific material of the fiber fabric layer 30.

[0051] According to an embodiment of the present invention, resin can be a thermoplastic resin or a thermosetting resin. Thermoplastic resin can include polyester, polyvinyl chloride, polyamide, polystyrene, polyacrylate, polyolefin, polyether, polycarbonate, polyacrylonitrile, polysulfone, polyketone, polyamide, polyimide, polyacrylic acid or their copolymers, mixtures or modified substances. Thermosetting resin can be epoxy resin, polyester resin, vinyl ester, bismaleimide, thermosetting polyimide, cyanate ester, etc. However, the present invention does not specifically limit the type of thermoplastic resin or thermosetting resin.

[0052] According to an embodiment of the present invention, the gram weight of the mesh cloth layer 20 may be less than the gram weight of the fiber fabric layer 30. By making the gram weight of the mesh cloth layer 20 less than the gram weight of the fiber fabric layer 30, the weight of the mesh cloth layer 20 can be reduced while improving the peel strength. As an example, the gram weight of the upper mesh cloth layer 21 and the lower mesh cloth layer 22 is 50 g / m 2 -200g / m 2 If the weight of the upper mesh fabric layer 21 and the lower mesh fabric layer 22 is less than 50 g / m 2 , the area of ​​the first mesh hole 21a and the second mesh hole will be too large, and the resin block connecting the mesh cloth layer 20 and the fiber fabric layer 30 cannot be effectively formed. If the weight of the upper mesh cloth layer 21 and the lower mesh cloth layer 22 is greater than 200g / m 2 , it is not conducive to reducing the weight of the mesh cloth layer 20, or the area of ​​the first mesh hole 21a and the second mesh hole will be too small, resulting in too small a resin block, and the degree of improvement of the bonding strength between the core material layer 10 and the fiber fabric layer 30 will be insufficient.

[0053] According to an embodiment of the present invention, the area of ​​the first mesh hole 21a and the second mesh hole is 2 mm 2 -9mm 2 When the area of ​​the first mesh hole 21a and the second mesh hole is less than 2mm 2 When the area of ​​the first mesh hole 21a and the second mesh hole is too small, the resin block is too small, and the degree of improvement of the bonding strength between the core material layer 10 and the fiber fabric layer 30 is insufficient. 2 When the mesh holes 21 a and the second mesh holes are too large, the resin blocks connecting the mesh cloth layer 20 and the fiber fabric layer 30 cannot be effectively formed.

[0054] According to an embodiment of the present invention, the upper mesh cloth layer 21 and the lower mesh cloth layer 22 may be glass fiber or carbon fiber. As an example, the upper mesh cloth layer 21 and the lower mesh cloth layer 22 may both be glass fiber or both be carbon fiber. As an example, one of the upper mesh cloth layer 21 and the lower mesh cloth layer 22 may be glass fiber, and the other may be carbon fiber.

[0055] According to an embodiment of the present invention, the upper mesh fabric layer 21 and the lower mesh fabric layer 22 are both configured as a single layer. By configuring the upper mesh fabric layer 21 and the lower mesh fabric layer 22 as a single layer, the weight of the mesh fabric layer 20 can be reduced while improving the peel strength, without affecting the overall performance of the sandwich structure 100.

[0056] According to an embodiment of the present invention, Figure 3 As shown, the upper mesh fabric layer 21 may include cross-woven first warp yarns 21b and first weft yarns 21c, and the first warp yarns 21b and the first weft yarns 21c surround the first mesh holes 21a. Although not shown, similar to the upper mesh fabric layer 21, the lower mesh fabric layer 22 may include cross-woven second warp yarns and second weft yarns, and the second warp yarns and the second weft yarns surround the second mesh holes.

[0057] According to an embodiment of the present invention, Figure 3 As shown, the first warp yarn 21b is woven orthogonally with the first weft yarn 21c and the first warp yarn 21b surrounds the first weft yarn 21c. Although not shown, similar to the upper mesh cloth layer 21, the second warp yarn is woven orthogonally with the second weft yarn and the second warp yarn surrounds the second weft yarn. According to an embodiment of the present invention, by making the first warp yarn 21b surround the first weft yarn 21c and the second warp yarn surround the second weft yarn, the intersection of the warp yarn and the weft yarn can be thickened, the amount of dipping can be increased without increasing the yarn, and the interface performance can be improved.

[0058] According to an embodiment of the present invention, Figure 2 As shown, a plurality of grooves 11 may be provided in the core material layer 10, and the plurality of grooves 11 extend from the upper surface of the core material layer 10 toward the lower surface of the core material layer 10 by a predetermined distance and are separated from the lower surface of the core material layer 10. For example, the plurality of grooves 11 may be formed in two directions orthogonal to each other. When the resin is poured, the resin may fill at least a portion of the plurality of grooves 11, thereby improving the bonding strength between the core material layer 10 and the fiber fabric layer 30. According to an embodiment of the present invention, a plurality of perforations (not shown) are further provided in the core material layer 10, and the plurality of perforations may penetrate the core material layer 10. When the resin is poured, the resin may fill at least a portion of the plurality of perforations, thereby improving the bonding strength between the core material layer 10 and the fiber fabric layer 30. The present invention does not specifically limit the width of the grooves 11 and the diameter of the perforations.

[0059] When the sandwich structure 100 is used to form the shell of the fan blade, the groove 11 opened in the core material layer 10 is relatively deep, for example, a bottom of 1.5 mm may be left. At this time, in order to prevent the core material layer 10 from breaking or falling apart after the grooves are opened, the lower mesh cloth layer 22 may be glued to the lower surface of the core material layer 10 before the grooves are opened, so that after the grooves are opened, the lower mesh cloth layer 22 plays a connecting role, which can prevent the core material layer 10 from breaking or falling apart after the grooves are opened. When the sandwich structure 100 is used to form the shell of the fan blade, the upper mesh cloth layer 21 and the upper fiber fabric layer 31 may be woven together and then laid on the upper surface of the core material layer 10 after the grooves are opened to simplify the process.

[0060] According to an embodiment of the present invention, the area of ​​the second mesh hole can be smaller than the area of ​​the first mesh hole 21a. Since the lower mesh cloth layer 22 not only improves the bonding strength between the core material layer 10 and the lower fiber fabric layer 32, but also prevents the core material layer 10 from breaking or breaking apart after slotting, the area of ​​the second mesh hole can be appropriately reduced compared with the first mesh hole 21a, thereby improving the support strength of the lower mesh cloth layer 22.

[0061] When the sandwich structure 100 is used to form the web of a wind turbine blade, the groove 11 opened in the core material layer 10 is relatively shallow (for example, the groove depth may be 2 mm), and the core material layer 10 is not easy to break or fall apart after the grooves are opened. Therefore, the lower mesh cloth layer 22 and the upper mesh cloth layer 21 may be bonded after the core material layer 10 is grooved. As an example, the upper mesh cloth layer 21 and the upper fiber fabric layer 31 may be woven together and then laid on the upper surface of the grooved core material layer 10, and the lower mesh cloth layer 22 and the lower fiber fabric layer 32 may be woven together and then laid on the lower surface of the grooved core material layer 10 to simplify the process.

[0062] The present invention does not specifically limit the thickness of the core material layer 10, and the thickness of the core material layer 10 can be determined according to the model of the fan blade or the purpose of the sandwich structure. In addition, the present invention does not specifically limit the number of layers of the upper fiber fabric layer 31 and the lower fiber fabric layer 32, and the number of layers of the upper fiber fabric layer 31 and the lower fiber fabric layer 32 can be determined according to the model of the fan blade or the purpose of the sandwich structure. The number of layers of the upper fiber fabric layer 31 and the lower fiber fabric layer 32 can be the same or different, and there is no specific limitation on this.

[0063] Method for manufacturing sandwich structure

[0064] Below, refer to Figures 4 to 6 And combined with Figure 1 and Figure 2 A method for manufacturing a sandwich structure according to an embodiment of the present invention is described. In describing the method for manufacturing a sandwich structure according to an embodiment of the present invention, contents overlapping with the above description will be omitted.

[0065] Figure 4is a flow chart of a method for manufacturing a sandwich structure according to an embodiment of the present invention; Figure 5 is a flow chart of a method for forming a stack according to one embodiment of the present invention; Figure 6 is a flow chart of a method for forming a stack according to another embodiment of the present invention.

[0066] like Figure 4 As shown, the method for manufacturing a sandwich structure according to an embodiment of the present invention may include forming a stacked body ( S100 ) and pouring a resin into the stacked body and curing the resin ( S200 ).

[0067] In step S100, a stacked body may be formed. The stacked body may include the core material layer 10, the mesh cloth layer 20, and the fiber fabric layer 30 described above. The mesh cloth layer 20 may include an upper mesh cloth layer 21 disposed on the upper surface of the core material layer 10 and having a first mesh hole 21a and a lower mesh cloth layer 22 disposed on the lower surface of the core material layer 10 and having a second mesh hole, and the fiber fabric layer 30 may include an upper fiber fabric layer 31 disposed on the upper surface of the upper mesh cloth layer 21 and a lower fiber fabric layer 32 disposed on the lower surface of the lower mesh cloth layer 22. The materials and structures of the core material layer 10, the mesh cloth layer 20, and the fiber fabric layer 30 have been described above, and will not be repeated here.

[0068] In step S200, resin may be infused into the stacked body using, for example, a vacuum resin infusion molding method and the resin may be cured. The resin may infiltrate the core material layer 10, the mesh cloth layer 20, and the fiber fabric layer 30 and form a composite molded body of the resin, the core material layer 10, the mesh cloth layer 20, and the fiber fabric layer 30 after curing. The resin may form a resin block 40 in at least a portion of the first mesh hole 21a and at least a portion of the second mesh hole to improve the peel strength between the core material layer 10 and the upper fiber fabric layer 31 and the lower fiber fabric layer 32. In addition, during the process of infusing the resin, the resin may flow into the groove 11 of the core material layer 10 and the hole of the core material layer 10 through the first mesh hole 21a and the second mesh hole.

[0069] When the sandwich structure of the present invention forms a prefabricated part, the prefabricated part of the sandwich structure can be formed by vacuum infusing resin after forming a stacked body, and when a wind blade is subsequently formed, the prefabricated part of the sandwich structure is hoisted to a designated position. For example, when the sandwich structure of the present invention forms the web of a wind blade, it can be formed into a prefabricated part. In addition, the sandwich structure can also be formed into a prefabricated part instead of a stacked body when the wind blade is layered and integrally infused with the layers of the wind blade. For example, when the sandwich structure of the present invention forms the shell of a wind blade, the stacked body can be formed when the wind blade is layered and integrally infused with the layers of the wind blade. However, the present invention is not limited thereto, and when the sandwich structure of the present invention forms the shell of a wind blade, it can also be formed into a prefabricated part.

[0070] Depending on the specific use of the sandwich structure, the steps of forming the stack may be different. Specifically, when the core material structure is used for a web or a blade shell, the steps of forming the stack are different because the depth of the grooves of the core material layer 10 in the core material structure for the web and the core material structure for the blade shell are different. As described above, the groove depth of the core material layer 10 of the core material structure for the blade shell requires the use of the lower mesh cloth layer 22 to prevent the core material layer 10 from breaking or falling apart after grooving, that is, the lower mesh cloth layer 22 needs to be bonded to the lower surface of the core material layer 10 before grooving. In addition, in order to save process, the upper mesh cloth layer 21 and the upper fiber fabric layer 31 can be woven together and then bonded to the upper surface of the core material layer 10. The grooves of the core material layer 10 of the core material structure used for the web are shallow, so there is no need to stick the lower mesh cloth layer 22 before grooving to prevent breakage or loosening. In order to save process, the upper mesh cloth layer 21 and the upper fiber fabric layer 31 can be woven together and then pasted to the upper surface of the core material layer 10, and the lower mesh cloth layer 22 and the lower fiber fabric layer 32 can be woven together and then pasted to the lower surface of the core material layer 10.

[0071] Specifically, Figure 5 As shown, when the core material structure according to the present invention is used to form a blade shell, the steps of forming a stack may include: bonding the lower mesh cloth layer 22 to the lower surface of the core material layer 10 (S111); cutting the core material layer 10 to form a plurality of grooves 11, wherein the plurality of grooves 11 extend from the upper surface of the core material layer 10 toward the lower surface of the core material layer 10 by a predetermined distance and are separated from the lower surface of the core material layer 10 (S112); laying the lower fiber fabric layer 32 and the core material layer 10 bonded with the lower mesh cloth layer 22 on the mold in sequence (S113); weaving the upper mesh cloth layer 21 and the upper fiber fabric layer 31 together and laying them on the upper surface of the core material layer 10 (S114).

[0072] In step S111 , the lower mesh cloth layer 22 is bonded to the lower surface of the core material layer 10 . The specific bonding method is not limited. For example, adhesive (eg, hot melt adhesive) may be used to partially fix the lower mesh cloth layer 22 to the lower surface of the core material layer 10 .

[0073] In step S112, the core material layer 10 may be cut to form a plurality of grooves 11. The plurality of grooves 11 may be deep grooves and may be formed along two directions orthogonal to each other. The structure of the grooves 11 has been described above and will not be described in detail here.

[0074] In step S113, the lower fiber fabric layer 32 and the core material layer 10 bonded with the lower mesh fabric layer 22 are sequentially laid on the mold. The mold can be a conventional mold for forming a sandwich structure of a shell of a wind turbine blade in the art, and the present invention does not impose any specific restrictions on its specific structure.

[0075] In step S114, the upper mesh cloth layer 21 and the upper fiber fabric layer 31 may be woven together and laid on the upper surface of the core material layer 10. According to the present invention, after the grooved core material layer 10 is laid on the mold, the upper mesh cloth layer 21 and the upper fiber fabric layer 31 are laid on the upper surface of the core material layer 10. Since the sandwich structure used for the blade shell has a certain curvature, if the upper mesh cloth layer 21 is laid on the upper surface of the core material layer 10 before the grooved core material layer 10 is laid on the mold, the shape of the core material layer 10 will be limited when it is laid, and it cannot fit the shape of the mold.

[0076] According to an embodiment of the present invention, adhesive glue (eg, hot melt adhesive) may be used to partially fix the upper mesh cloth layer 21 and the upper fiber fabric layer 31 on the upper surface of the core material layer 10 .

[0077] like Figure 6 As shown, when the core material structure according to the present invention is used to form a web, the steps of forming a stack may include: cutting the core material layer 10 to form a plurality of grooves 11, wherein the plurality of grooves 11 extend from the upper surface of the core material layer 10 toward the lower surface of the core material layer 10 by a predetermined distance and are separated from the lower surface of the core material layer 10 (S121); weaving the lower fiber fabric layer 32 and the lower mesh cloth layer 22 together and laying them on a mold, wherein the lower mesh cloth layer 22 is located on the lower fiber fabric layer 32 (S122); laying the core material layer 10 on the lower mesh cloth layer 22 (S123); weaving the upper mesh cloth layer 21 and the upper fiber fabric layer 31 together and laying them on the upper surface of the core material layer 10 (S124).

[0078] In step S121, the core material layer 10 may be cut to form a plurality of grooves 11. The plurality of grooves 11 may be shallow grooves and may be formed along two directions orthogonal to each other. The structure of the grooves 11 has been described above and will not be described in detail here.

[0079] In step S122, the lower fiber fabric layer 32 and the lower mesh cloth layer 22 are woven together and laid on the mold, and the lower mesh cloth layer 22 is located on the lower fiber fabric layer 32. There is no obvious order relationship between step S121 and step S122, for example, step S121 and step S122 can be performed simultaneously, or step S121 can be performed first and then step S122, or step S122 can be performed first and then step S121.

[0080] In step S123 , the core material layer 10 is laid on the lower mesh cloth layer 22 .

[0081] In step S124 , the upper mesh cloth layer 21 and the upper fiber fabric layer 31 are woven together and then laid on the upper surface of the core material layer 10 .

[0082] Fan blades

[0083] According to an embodiment of the present invention, a wind blade comprising the sandwich structure may be provided. As described above, the sandwich structure 100 may constitute at least a portion of a web and / or a blade shell of a wind blade.

[0084] Wind turbines

[0085] According to an embodiment of the present invention, a wind turbine generator set including the above-mentioned wind turbine blade may also be provided.

[0086] According to the sandwich structure and the method for manufacturing the sandwich structure of the present invention as described above, beneficial technical effects not limited to the following description can be achieved.

[0087] According to the present invention, mesh cloth layers are provided on both sides of the core material layer, which can improve the interface performance of both sides and ensure the consistency of the interface performance of both sides, thereby improving the peeling strength of both sides, which is more conducive to ensuring the overall strength of the sandwich structure.

[0088] According to the present invention, the mesh cloth layer and the fiber fabric layer can be woven together in advance and laid together with the fiber fabric layer without increasing the number of steps.

[0089] According to the present invention, the support strength and the peeling strength can be improved at the same time by adjusting the area of ​​the second mesh holes and the area of ​​the first mesh holes.

[0090] According to the present invention, the shape of the core material layer during laying is not affected and can be fitted to the shape of the mold.

[0091] While exemplary embodiments of the present invention have been described in detail with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the claims.

Claims

1. A sandwich structure of a fan blade, characterized in that: The sandwich structure (100) comprises: A core material layer (10); A mesh cloth layer (20), comprising an upper mesh cloth layer (21) disposed on the upper surface of the core material layer (10) and having first mesh holes (21a) and a lower mesh cloth layer (22) disposed on the lower surface of the core material layer (10) and having second mesh holes; A fiber fabric layer (30), comprising an upper fiber fabric layer (31) arranged on the upper surface of the upper mesh fabric layer (21) and a lower fiber fabric layer (32) arranged on the lower surface of the lower mesh fabric layer (22); The resin is compositely molded with the core material layer (10), the mesh cloth layer (20) and the fiber fabric layer (30), and forms a resin block (40) in at least a portion of the first mesh holes (21a) and at least a portion of the second mesh holes.

2. The sandwich structure according to claim 1, characterized in that: The upper mesh cloth layer (21) and the upper fiber fabric layer (31) are woven together, and / or the lower mesh cloth layer (22) and the lower fiber fabric layer (32) are woven together.

3. The sandwich structure according to claim 1 or 2, characterized in that: A plurality of grooves (11) are provided in the core material layer (10), and the plurality of grooves (11) extend a predetermined distance from the upper surface of the core material layer (10) toward the lower surface of the core material layer (10) and are separated from the lower surface of the core material layer (10), and the resin fills at least a portion of the plurality of grooves (11).

4. The sandwich structure according to claim 3, characterized in that: The upper mesh cloth layer (21) includes cross-woven first warp yarns (21b) and first weft yarns (21c), wherein the first warp yarns (21b) and the first weft yarns (21c) surround the first mesh holes (21a), and the lower mesh cloth layer (22) includes cross-woven second warp yarns and second weft yarns, wherein the second warp yarns and the second weft yarns surround the second mesh holes.

5. The sandwich structure according to claim 4, characterized in that: The first warp yarn (21b) is woven orthogonally to the first weft yarn (21c) and the first warp yarn (21b) surrounds the first weft yarn (21c), and the second warp yarn is woven orthogonally to the second weft yarn and the second warp yarn surrounds the second weft yarn.

6. The sandwich structure according to claim 4, characterized in that: The area of ​​the second mesh holes is smaller than the area of ​​the first mesh holes (21a).

7. The sandwich structure according to claim 4, characterized in that: The weight of the upper mesh cloth layer (21) and the lower mesh cloth layer (22) is 50 g / m 2 -200g / m 2 The area of ​​the first mesh hole (21a) and the second mesh hole is 2 mm 2 -9mm 2 .

8. The sandwich structure according to claim 1, characterized in that: The gram weight of the mesh cloth layer (20) is less than the gram weight of the fiber fabric layer (30).

9. The sandwich structure according to claim 1, characterized in that: The upper mesh cloth layer (21) and the lower mesh cloth layer (22) are both configured as single layers.

10. The sandwich structure according to claim 1, characterized in that The upper mesh cloth layer (21) and the lower mesh cloth layer (22) are made of glass fiber or carbon fiber.

11. The sandwich structure according to claim 3, characterized in that: The plurality of grooves (11) are formed along two directions orthogonal to each other. The core material layer (10) is also provided with a plurality of through holes, the plurality of through holes passing through the core material layer (10), and the resin fills at least a portion of the through holes.

12. The sandwich structure according to claim 1, characterized in that The core material layer (10) comprises polyvinyl chloride foam, polyethylene terephthalate foam, high-performance high-chlorinated polyethylene foam, polyurethane foam, polystyrene foam, polyethylene foam, polymethacrylimide foam, polyamide foam, polyimide foam, polyarylethernitrile foam, natural fiber foam, balsa wood, paulownia wood or a composite of at least two of these foams, and / or The fiber fabric layer (30) comprises glass fiber, carbon fiber, basalt fiber, aramid fiber, natural fiber, ultra-high molecular weight polyethylene fiber or a mixed fabric of at least two of them, and / or The resin is a thermoplastic resin or a thermosetting resin.

13. A method for manufacturing a sandwich structure of a fan blade, characterized in that: The manufacturing method comprises: A stacked body is formed, wherein the stacked body comprises a core material layer (10), a mesh cloth layer (20) and a fiber fabric layer (30), wherein the mesh cloth layer (20) comprises an upper mesh cloth layer (21) disposed on the upper surface of the core material layer (10) and having first mesh holes (21a) and a lower mesh cloth layer (22) disposed on the lower surface of the core material layer (10) and having second mesh holes, and the fiber fabric layer (30) comprises an upper fiber fabric layer (31) disposed on the upper surface of the upper mesh cloth layer (21) and a lower fiber fabric layer (32) disposed on the lower surface of the lower mesh cloth layer (22); Resin is poured into the stack and cured, so that the resin is composite-formed with the core material layer (10), the mesh cloth layer (20) and the fiber fabric layer (30), and the resin forms a resin block (40) in at least a portion of the first mesh holes (21a) and at least a portion of the second mesh holes.

14. The manufacturing method according to claim 13, characterized in that: The steps of forming the stack include: Bonding the lower mesh fabric layer (22) to the lower surface of the core material layer (10); Cutting the core material layer (10) to form a plurality of grooves (11), wherein the plurality of grooves (11) extend from the upper surface of the core material layer (10) toward the lower surface of the core material layer (10) by a predetermined distance and are separated from the lower surface of the core material layer (10); Laying the lower fiber fabric layer (32) and the core material layer (10) bonded with the lower mesh fabric layer (22) on the mold in sequence; The upper mesh cloth layer (21) and the upper fiber fabric layer (31) are woven together and then laid on the upper surface of the core material layer (10).

15. The manufacturing method according to claim 13, characterized in that: The steps of forming the stack include: Cutting the core material layer (10) to form a plurality of grooves (11), wherein the plurality of grooves (11) extend from the upper surface of the core material layer (10) toward the lower surface of the core material layer (10) by a predetermined distance and are separated from the lower surface of the core material layer (10); Weaving the lower fiber fabric layer (32) and the lower mesh cloth layer (22) together and laying them on a mold, wherein the lower mesh cloth layer (22) is located on the lower fiber fabric layer (32); Laying the core material layer (10) on the lower mesh cloth layer (22); The upper mesh cloth layer (21) and the upper fiber fabric layer (31) are woven together and then laid on the upper surface of the core material layer (10).

16. A fan blade, characterized in that: The wind blade comprises a sandwich structure (100) of a wind blade according to any one of claims 1 to 12.

17. The fan blade according to claim 16, characterized in that: The sandwich structure (100) constitutes at least a part of at least one of a web and a blade shell of the wind blade.

18. A wind turbine generator set, characterized in that: The wind turbine generator set comprises the wind turbine blade according to claim 16 or 17.

Images