CN112662010A

CN112662010A - Continuous carbon nanotube fiber reinforced resin matrix composite material, wind power blade and preparation method thereof

Info

Publication number: CN112662010A
Application number: CN202011519523.9A
Authority: CN
Inventors: 梁嫄; 孙建旭; 马豪
Original assignee: Envision Energy Co Ltd
Current assignee: Envision Energy Co Ltd
Priority date: 2020-12-21
Filing date: 2020-12-21
Publication date: 2021-04-16
Anticipated expiration: 2040-12-21
Also published as: CN112662010B; WO2022134234A1

Abstract

The invention relates to a continuous carbon nanotube fiber reinforced resin matrix composite, a wind power blade and a preparation method thereof, wherein the continuous carbon nanotube fiber reinforced resin matrix composite comprises a resin matrix and continuous carbon nanotube fibers doped in the resin matrix, and the wind power blade is formed by stacking a plurality of continuous carbon nanotube fiber reinforced resin matrix composites. Compared with the prior art, the wind power blade has good mechanical property, can monitor the strain of the carbon nanotube fiber composite material in real time, and improves the competitiveness and safety of the wind power blade and a fan product.

Description

Continuous carbon nanotube fiber reinforced resin matrix composite material, wind power blade and preparation method thereof

Technical Field

The invention relates to the technical field of wind driven generators, in particular to a continuous carbon nanotube fiber reinforced resin matrix composite, a wind power blade and a preparation method thereof.

Background

Wind energy is a clean energy with large storage and high safety. The wind power generation needs to utilize the blades at the top end of the fan to drive the rotation by wind energy to generate lift force, and the lift force is further converted into torque through a transmission chain in the engine room to drive the generator to generate power. Under the same condition, the larger the impeller is, the more wind energy can be captured, so that the longer the blade of the fan is, the higher the requirements on the design of the blade are put forward. The optimal design of the blade is one of the core technologies of wind power generation. At present, most of blades are in a traditional structural form of two shells which are divided into a pressure surface and a suction surface, each shell consists of a sandwich plate consisting of glass fiber reinforced plastics and a core material and main bearing parts, namely a main beam and a tail edge beam, the main beam contributes to most of flapping rigidity, and the tail edge beam contributes to most of shimmy rigidity. The two shells are internally provided with web supports to ensure sufficient stability of the structure, and finally the webs and the shells are combined together through a bonding process. The longer the blade, the greater the deformation, the more efficient material is needed to increase the blade stiffness.

For example, a conventional main beam of a wind turbine blade is laid on a main beam mold by using a glass fiber fabric, and resin is introduced by means of vacuum infusion and finally cured. The requirement on rigidity cannot be met by adopting the glass fiber for the oversized blade, so that additives with higher modulus and high strength need to be introduced. At present, part of wind power manufacturers utilize continuous carbon fibers to manufacture a wind power blade main beam to improve the rigidity of the blade, the modulus of the adopted traditional continuous carbon fibers is generally 230GPa-260GPa, but the mechanical property of the traditional continuous carbon fibers still cannot well meet the requirement of the wind power blade.

Chinese patent publication No. CN108623999A discloses a composite material for a wind driven generator blade and a preparation method thereof, wherein the composite material is composed of the following raw materials in percentage by mass: 35-60% of epoxy resin, 10-30% of glass fiber, 2-5% of carbon nano tube, 1.4-5.0% of processing aid, 4-6% of diluent, 0.2-0.5% of coupling agent and the balance of curing agent. However, the carbon nanotubes contained in the composite material are nano-particles, more interface between the fiber and the resin is enhanced, the tensile strength, the fatigue strength, the shear strength and the impact resistance are improved, and the tensile modulus of the composite material is dominated by the modulus of the fiber, so that the material with the increased dispersion term does not greatly contribute to the unidirectional tensile modulus of the composite material.

In addition, the design life of the fan is generally 20-25 years, a sub-health operation state (namely, the deformation is too large and cannot be recovered in time) often occurs due to adverse factors such as severe weather during air operation, if the condition is not found in time, the maintenance time is delayed, overhaul is caused or the blade has to be replaced, and the maintenance cost is increased.

Therefore, there is a great need in the art for a wind turbine blade that is strong and can monitor usage conditions.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a continuous carbon nanotube fiber reinforced resin matrix composite.

The application also aims to provide a wind power blade prepared from the composite material and a preparation method thereof.

In order to achieve the object of the present invention, the present application provides the following technical solutions.

In a first aspect, the present application provides a continuous carbon nanotube fiber reinforced resin-based composite material comprising a resin matrix and continuous carbon nanotube fibers doped within the resin matrix. The continuous carbon nanotube fiber has high impact strength and tensile strength, and the two performances are the two most important factors during the operation of the wind power blade, so that the composite material prepared by doping the continuous carbon nanotube fiber in the resin matrix perfectly conforms to the application requirements of the wind power blade. In addition, research shows that the mechanical and electrical properties of the carbon nanotube fiber have certain coupling effect. During loading and unloading, the electrical resistance of the fiber increases/decreases as the amount of strain becomes an increase/decrease in stress. It is known that the fiber resistance change is consistent with its strain/stress change. The 2% strain amount generates a resistance change of 8.5 to 9.3 Ω, that is, the resistance change of the fiber caused by the elastic deformation is cyclically reversible. Thus, the magnitude of the elastic deformation of the composite material can be monitored by monitoring the change in resistance of the composite material.

In one embodiment of the first aspect, the doping amount of the continuous carbon nanotube fibers in the composite material is 40% to 80%. If the doping ratio is too low, the rigidity of the composite material is too low to reach the design modulus; if the doping ratio is too large, the process is difficult to realize.

In one embodiment of the first aspect, the continuous carbon nanotube fiber has a young's modulus of greater than 300 GPa.

In one embodiment of the first aspect, the composite material is doped with hybrid fibers, and the doped volume percentage of the hybrid fibers is 0 to 20%. The addition of other fibers can not only enhance the functionality of the composite material, such as impact resistance, electrical conductivity and thermal conductivity, but also can obtain the composite material with specific modulus and strength by adding fibers with different ratios.

In one embodiment of the first aspect, the hybrid fiber includes one or more of carbon fiber, glass fiber, aramid fiber, boron fiber, basalt fiber, and ultra-high modulus polyethylene fiber, wherein the number of filaments in the carbon fiber is 12k to 50k, and the modulus of the ultra-high modulus polyethylene fiber is 87 GPa to 172 GPa.

In one embodiment of the first aspect, the resin matrix comprises a thermosetting resin or a thermoplastic resin, wherein the thermosetting resin comprises one of an epoxy resin, a vinyl resin, an unsaturated polyester resin, a polyurethane resin, or a phenolic resin, and the thermoplastic resin comprises one of a polypropylene, a polyethylene, a polyvinyl chloride, a polystyrene, a polyacrylonitrile-butadiene-styrene, a polyamide, a polyetheretherketone, or a polyphenylene sulfide resin.

In a second aspect, the present application further provides a wind power blade, the wind power blade includes two casings and webs, the casing includes sandwich panel and main load-bearing part, main load-bearing part includes girder and trailing edge roof beam, girder and/or trailing edge roof beam are formed by the polylith as above continuous fibers reinforcing resin base combined material piles up.

In one embodiment of the second aspect, the main and/or trailing edge beams are stacked from 1 to 300 pieces of composite material.

In a third aspect, the present application provides a method for manufacturing a wind turbine blade as described above, wherein the continuous carbon nanotube fibers are introduced during the forming process of the main beam and/or the trailing edge beam.

In one embodiment of the third aspect, the forming process comprises one of vacuum infusion forming, fiber pultrusion or prepreg forming.

In one embodiment of the third aspect, the main beam and/or the trailing edge beam is provided with a resistance acquisition instrument. The main beam and/or the tail edge beam are/is prepared from the composite material, so that the elastic deformation of the main beam/the tail edge beam is coupled with the resistance change of the main beam/the tail edge beam, and the elastic deformation can be obtained by setting the resistance acquisition instrument to monitor the resistance change of the main beam/the tail edge beam, so that the running state of the blade is monitored.

Compared with the prior art, the invention has the beneficial effects that:

the carbon nanotube fiber has higher specific modulus than the traditional carbon fiber material, so that the weight of the blade can be further reduced, and other functional effects can be achieved. Compared with a glass fiber blade, the key force bearing part based on the wind power blade design can reduce weight by 20% -40% by introducing novel continuous fibers and optimizing combination. And the main beam and/or the tail edge beam are/is provided with a resistance acquisition instrument, and the resistance change of the main beam/the tail edge beam is monitored to obtain the strain change of the main beam/the tail edge beam, so that the running state of the blade is monitored.

Drawings

FIG. 1 is a typical cross-sectional view of a wind blade according to the present invention;

FIG. 2 is a cross-sectional view of a wind blade main beam of the present invention;

fig. 3 is a cross-sectional view of the composite material for wind power in example 1.

In the attached drawings, 1 is a wind power blade, 2 is a front edge, 31 is a main beam, 32 is a tail edge beam, 4 is a web, 5 is a pressure surface, 6 is a suction surface, 7 is a tail edge, 8 is a composite material plate, 9 is glass fiber, 10 is basalt fiber, 11 is a resin matrix, and 12 is continuous carbon nanotube fiber.

Detailed Description

It should be noted that the components in the figures may be exaggerated and not necessarily to scale for illustrative purposes. In the figures, identical or functionally identical components are provided with the same reference symbols.

In the present invention, "disposed on …", "disposed over …" and "disposed over …" do not exclude the presence of an intermediate therebetween, unless otherwise specified. Further, "disposed on or above …" merely indicates the relative positional relationship between two components, and may also be converted to "disposed below or below …" and vice versa in certain cases, such as after reversing the product direction.

In the present invention, the embodiments are only intended to illustrate the aspects of the present invention, and should not be construed as limiting.

In the present invention, the terms "a" and "an" do not exclude the presence of a plurality of elements, unless otherwise specified.

It is further noted herein that in embodiments of the present invention, only a portion of the components or assemblies may be shown for clarity and simplicity, but those of ordinary skill in the art will appreciate that, given the teachings of the present invention, required components or assemblies may be added as needed in a particular scenario.

It is also noted herein that, within the scope of the present invention, the terms "same", "equal", and the like do not mean that the two values are absolutely equal, but allow some reasonable error, that is, the terms also encompass "substantially the same", "substantially equal". By analogy, in the present invention, the terms "perpendicular", "parallel" and the like in the directions of the tables also cover the meanings of "substantially perpendicular", "substantially parallel".

The numbering of the steps of the methods of the present invention does not limit the order of execution of the steps of the methods. Unless specifically stated, the method steps may be performed in a different order.

Unless otherwise defined, technical or scientific terms used herein in the specification and claims should have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. All numerical values recited herein as between the lowest value and the highest value are intended to mean all values between the lowest value and the highest value in increments of one unit when there is more than two units difference between the lowest value and the highest value.

While specific embodiments of the invention will be described below, it should be noted that in the course of the detailed description of these embodiments, in order to provide a concise and concise description, all features of an actual implementation may not be described in detail. Modifications and substitutions to the embodiments of the present invention may be made by those skilled in the art without departing from the spirit and scope of the present invention, and the resulting embodiments are within the scope of the present invention.

The traditional wind power blade has the defects of insufficient mechanical property and conductivity, and mechanical properties such as rigidity and the like, so that the application of the wind power blade is limited to a certain extent. The application aims to provide a continuous fiber reinforced resin matrix composite material for a wind power blade. The material relates to one or more continuous fibers, wherein macroscopic continuous carbon nanotube fibers assembled by nanometer material carbon nanotubes are contained. The introduction of the nanofiber can greatly improve the mechanical and electrical properties of the fiber reinforced resin matrix composite material, provide more superior mechanical and functional materials for the structural design of the wind power blade, and improve the competitiveness of the wind power blade and a fan product.

The invention aims to improve the material performance of the main bearing structure of the wind power blade, and introduces novel continuous carbon nanotube fibers in the forming process of a wind power main beam or a tail edge beam, so that the mechanical and electrical properties of the formed composite material are improved. The forming process comprises vacuum infusion, fiber pultrusion and prepreg forming. In order to achieve the purpose, the continuous fiber reinforced resin matrix composite material for the wind power blade comprises fibers assembled by nano material carbon nano tubes.

The composite material may or may not contain hybrid fiber besides the continuous carbon nanotube fiber, and the hybrid fiber includes one or more of carbon fiber, glass fiber, aramid fiber, boron fiber, basalt fiber and ultrahigh modulus polyethylene fiber.

In the composite material, the resin matrix comprises a thermosetting epoxy resin, a vinyl resin, an unsaturated polyester resin, a polyurethane resin, a phenolic resin, and a thermoplastic resin. Thermoplastic polypropylene, polyethylene, polyvinyl chloride, polystyrene, polyacrylonitrile-butadiene-styrene, polyamide, polyether ether ketone and polyphenylene sulfide resin.

The invention has the advantages that: the carbon nanotube fiber has higher specific modulus than the traditional carbon fiber material, so that the weight of the blade can be further reduced, and other functional effects can be achieved. Compared with a glass fiber blade, the key force bearing part based on the wind power blade design can reduce weight by 20% -40% by introducing novel continuous fibers and optimizing combination. The main beam and the tail edge beam adopt carbon nano tube fibers, can be integrated with a lightning protection system, and serve as conductive media to lead current into a blade root from a blade tip, communicate the current to the whole machine and be grounded.

Examples

The following will describe in detail the embodiments of the present invention, which are implemented on the premise of the technical solution of the present invention, and the detailed embodiments and the specific operation procedures are given, but the scope of the present invention is not limited to the following embodiments.

Example 1

Preparing a continuous carbon nanotube fiber reinforced resin matrix composite material:

the method comprises the steps of hanging continuous carbon nanotube fibers 12 of Shenzhen Yuanwan science and technology Limited, which are commercially available, on a creel, hanging glass fibers 9 and boron fibers 10 on different rollers of the creel respectively, applying a proper drawing force to straighten the fibers and provide certain tension, uniformly mixing the continuous carbon nanotube fibers 12 with the glass fibers 9, the basalt fibers 10 and epoxy resin, and performing pultrusion through a mold with a specific cross-sectional shape to obtain a plate made of the continuous fiber reinforced resin matrix composite material, wherein the plate is structurally shown in FIG. 3, the epoxy resin is used as a resin matrix 11, and the continuous carbon nanotube fibers 12, the glass fibers 9 and the basalt fibers 10 are uniformly doped in the epoxy resin matrix, and in the embodiment, the volume ratio of the continuous carbon nanotube fibers 12 to the glass fibers 9 to the basalt fibers 10 to the resin matrix 11 is 50:5:5: 40.

A plurality of composite material sheets 8 (7 are shown as an example) are stacked to form a main beam 31 as shown in fig. 2.

Preparing a wind power blade:

the prepared main beams 31, the sandwich plate and the tail edge beam 32 are jointly poured to form two shells, wherein the sandwich plate is composed of glass fiber reinforced plastics and core materials, the tail edge beam 32 is made of the existing glass fiber pouring materials, the two shells are butted end to form the wind power blade 1, the wind power blade 1 comprises a front edge 2, a pressure surface 5, a suction surface 6 and a tail edge 7, meanwhile, a web plate 4 is fixed between the two main beams 31, and the concrete structure is shown in figure 1.

Example 2

Preparing a continuous fiber reinforced resin matrix composite material:

the method comprises the steps of mixing and weaving continuous carbon nanotube fibers and glass fibers which are purchased from Shenzhen Yuanjie science and technology Limited company to form a single-layer hybrid fabric, then uniformly and sequentially laying the multiple layers of hybrid fabric in a main beam mold, introducing a resin matrix in a vacuum environment, and curing and forming, thereby prefabricating the hybrid fiber trailing beam. In this example, the volume ratio between the continuous carbon nanotube fibers, the glass fibers, and the resin matrix was 60:10: 30.

Example 3

Preparing a continuous fiber reinforced resin matrix composite material:

the continuous carbon nanotube fiber purchased from Shenzhen Yuanwan science and technology Limited company is uniformly laid on a resin matrix film to prepare the carbon fiber prepreg. And then sequentially laying a plurality of layers of carbon fiber prepregs in a main beam mold, and heating to cure and mold the carbon fiber prepregs so as to prepare the prefabricated main beam. In this example, the volume ratio between the continuous carbon nanotube fibers and the resin matrix was 80: 20.

A plurality of composite material sheets are stacked to form a main beam and a trailing edge beam.

Example 4

Preparing a continuous fiber reinforced resin matrix composite material:

the method comprises the steps of applying a proper drawing force to continuous carbon nanotube fibers purchased from Shenzhen Yuanwan science and technology Limited company to straighten the fibers and have a certain tension, uniformly mixing the fibers with aramid fibers, basalt fibers and polystyrene resin, and performing pultrusion through a mold with a specific cross section shape to obtain a plate made of a continuous fiber reinforced resin matrix composite material, wherein in the embodiment, the mass ratio of the continuous carbon nanotube fibers to the aramid fibers to the basalt fibers to the resin matrix is 40: 10:10:40.

Example 5

The method comprises the steps of taking 100kg of continuous carbon nanotube fiber, hanging the continuous carbon nanotube fiber on a creel, simultaneously hanging basalt fiber and 100GPa ethylene fiber on different rolling shafts of the creel respectively, applying proper drawing force to straighten the fiber and have certain tension, uniformly mixing the continuous carbon nanotube fiber, the basalt fiber, the ethylene fiber and epoxy resin, and performing pultrusion through a die with a specific cross section shape to obtain a plate made of the continuous fiber reinforced resin matrix composite material, wherein the volume ratio of the continuous carbon nanotube fiber to the basalt fiber to the ethylene fiber to a resin matrix is 50:10:10:30 in the embodiment.

Example 6

Preparing a continuous fiber reinforced resin matrix composite material:

the method comprises the steps of mixing and weaving continuous carbon nanotube fibers and glass fibers which are purchased from Shenzhen Yuanjie science and technology Limited company to form a single-layer hybrid fabric, then uniformly and sequentially laying the multiple layers of hybrid fabric in a main beam mold, introducing polystyrene in a vacuum environment, and curing and forming to obtain the hybrid fiber trailing beam. In this example, the volume ratio between the continuous carbon nanotube fiber, the glass fiber, and the polystyrene was 70:1: 29.

Comparative example 1

The carbon fiber, the aramid fiber, the basalt fiber and the epoxy resin are uniformly mixed to obtain a plate made of the composite material, wherein the mass ratio of the carbon fiber to the aramid fiber to the basalt fiber to the resin matrix is 40:10:10: 40.

Comparative example 2

Preparing a continuous fiber reinforced resin matrix composite material:

firstly, uniformly mixing carbon nanotube powder and epoxy resin, wherein the mass percentage of the carbon nanotube and the epoxy resin is 2%. And uniformly mixing carbon fibers, aramid fibers, basalt fibers and epoxy resin doped with carbon nanotube powder to obtain a plate made of the composite material, wherein the mass ratio of the carbon fibers, the aramid fibers, the basalt fibers and the resin matrix is 40:10:10: 40.

Performance testing

The composite materials prepared in examples 1-6 and comparative examples 1 and 2 were subjected to modulus testing according to GB/T3354-.

The results are shown in the following table:

group of	Young's modulus (GPa)
		Example 1	176
Example 2	208
		Example 3	265
Example 4	154
		Example 5	186
Example 6	233
		Comparative example 1	114
Comparative example 2	118

From the test results we can see that: the tensile modulus of the carbon nanotube continuous fiber reinforced composite material is higher than that of the composite material reinforced by carbon fiber on the market and higher than that of the carbon fiber composite material reinforced by carbon nanotube powder.

In the running process of the fan, the wind speed can be measured through a wind measuring tower nearby or an anemometer or a laser radar at the top of the fan, the theoretical blade strain is calculated, the strain level is calculated by using the resistance change generated in the running process of the carbon nanotube fiber composite material with the electrical conductivity and the force-electricity coupling characteristics, the theoretical strain is compared with the running strain, if the deviation is overlarge, the damage of a main bearing structure is predicted, and people can be dispatched to carry out investigation and maintenance in time.

The embodiments described above are intended to facilitate the understanding and appreciation of the application by those skilled in the art. It will be readily apparent to those skilled in the art that various modifications to these embodiments may be made, and the generic principles described herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present application is not limited to the embodiments herein, and those skilled in the art who have the benefit of this disclosure will appreciate that many modifications and variations are possible within the scope of the present application without departing from the scope and spirit of the present application.

Claims

1. The continuous carbon nanotube fiber reinforced resin matrix composite is characterized by comprising a resin matrix and continuous carbon nanotube fibers doped in the resin matrix.

2. The continuous carbon nanotube fiber reinforced resin-based composite material according to claim 1, wherein the doping amount of the continuous carbon nanotube fiber in the composite material is 40% to 80%.

3. The continuous carbon nanotube fiber reinforced resin based composite of claim 1, wherein the continuous carbon nanotube fiber has a young's modulus of greater than 300 GPa.

4. The continuous carbon nanotube fiber reinforced resin-based composite material of claim 1, wherein the composite material is doped with hybrid fibers, and the volume percentage of the doped hybrid fibers is 0-20%.

5. The continuous carbon nanotube fiber reinforced resin-based composite material of claim 4, wherein the hybrid fiber comprises one or more of carbon fiber, glass fiber, aramid fiber, boron fiber, basalt fiber and ultra-high modulus polyethylene fiber, wherein the number of filaments in the carbon fiber is 12k to 50k, and the modulus of the ultra-high modulus polyethylene fiber is 87 GPa to 172 GPa.

6. The continuous carbon nanotube fiber reinforced resin based composite of claim 1, wherein the resin matrix comprises a thermosetting resin or a thermoplastic resin, wherein the thermosetting resin comprises one of an epoxy resin, a vinyl resin, an unsaturated polyester resin, a polyurethane resin, or a phenolic resin, and the thermoplastic resin comprises one of a polypropylene, a polyethylene, a polyvinyl chloride, a polystyrene, a polyacrylonitrile-butadiene-styrene, a polyamide, a polyetheretherketone, or a polyphenylene sulfide resin.

7. A wind power blade, wind power blade includes two casings and webs, the casing includes sandwich panel and main load-carrying parts, main load-carrying parts include girder and trailing edge roof beam, its characterized in that, girder and/or trailing edge roof beam are piled up by the polylith according to any one of claims 1 ~ 6 continuous fibers reinforcing resin base combined material.

8. The wind blade of claim 7 wherein the main and/or trailing edge beams are stacked from 1 to 300 pieces of composite material.

9. The wind blade of claim 7 wherein the main beam and/or the trailing edge beam is provided with a resistance collector.

10. The method for manufacturing the wind power blade according to any one of claims 7 to 9, wherein the continuous carbon nanotube fibers are introduced during the forming process of the main beam and/or the trailing edge beam.

11. The method of claim 10, wherein the forming process comprises one of vacuum infusion forming, fiber pultrusion, or prepreg forming.