Wind power blade provided with liquid damper and preparation method of wind power blade

Abstract

The invention discloses a wind power blade provided with liquid dampers and a preparation method of the wind power blade. 10-20 fish-shaped sheet type liquid dampers are arranged in series in the axial direction of an inner cavity of the blade in a section 10-20 m away from a blade tip, and the fish-shaped sheet type liquid dampers equivalently replace original blade webs in the section; the fish-shaped sheet type liquid dampers and the blade skin are bonded together through structural adhesive, and every two fish-shaped sheet type liquid dampers are bonded together through structural adhesive. The fish-shaped sheet type liquid damper is a sheet type prefabricated part with a fish-shaped section, the outer contour of the fish-shaped sheet type liquid damper is the clearance size of an inner cavity of the wing-shaped section of the blade, a flow guide partition plate perpendicular to the chord line of the blade is arranged in the fish-shaped sheet type liquid damper, and the inner cavity of the fish-shaped sheet type liquid damper is divided into zigzag and roundabout thin and long damping liquid flow channels by the flow guide partition plate. According to the blade provided with the liquid damper, vibration of the blade in the shimmy direction can be effectively restrained in the blade operation and shutdown states.

Description

Technical Field

[0001] The present invention relates to the technical field of wind power generation, and in particular to a wind power blade equipped with a liquid damper and a preparation method thereof. Background Art

[0002] The capacity of modern wind turbines has increased dramatically, and the length of blades has exceeded hundreds of meters. The blades are a standardized flexible cantilever beam structure. The structural vibration problem of the blades often plagues the operation of wind turbines and carries huge risks.

[0003] At present, there are two technical methods to suppress blade vibration: pneumatic damping and structural damping. Each technical route has active control and passive control damping mechanisms, but each has various advantages and disadvantages, and its practicality is subject to certain limitations.

[0004] The existing eddy current mass tuned damper can solve the vibration problem of the blade in the swing direction to a certain extent. However, it cannot achieve the level of lifelong maintenance-free and can only be used in the root cavity of the blade. The modal mass at this position is large, so the damping efficiency is relatively poor, requiring the use of a large number of dampers and high costs. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings and deficiencies of the prior art and to provide a wind turbine blade equipped with a liquid damper and a preparation method thereof. The damper structure and the blade bearing structure are designed as an integrated whole and are installed and used at the tip section, which can achieve efficient damping, low cost and lifelong maintenance-free.

[0006] To achieve the above-mentioned purpose, the technical solution provided by the present invention is as follows: a wind turbine blade equipped with a liquid damper, in a section 10-20m away from the blade tip, N fish-shaped sheet liquid dampers are arranged in series along the axial direction of the blade inner cavity, N is 10-20, and the sheet-type stacking is performed between two fish-shaped sheet liquid dampers, along the span direction of the blade, the shape and size of each fish-shaped sheet liquid damper is consistent with the inner cavity space of the section, so as to be adapted and embedded in the inner cavity of the blade, and the N fish-shaped sheet liquid dampers are equivalent to replace the original blade belly plate in the section; the fish-shaped The sheet-type liquid damper and the blade skin, as well as the two fish-shaped sheet-type liquid dampers, are bonded together with structural adhesive; the fish-shaped sheet-type liquid damper is a sheet-type prefabricated component with a fish-shaped cross-section, with a thickness of 50-150 mm, and its outer contour is the inner cavity clearance size of the blade airfoil cross-section; the interior of the fish-shaped sheet-type liquid damper is provided with a guide partition plate perpendicular to the blade chord line, and the guide partition plate divides the inner cavity of the fish-shaped sheet-type liquid damper into a tortuous and elongated damping liquid flow channel to extend the flow length of the damping liquid from the leading edge to the trailing edge of the blade.

[0007] Preferably, a disturbing fluid or a porous material damping filler is provided in the damping liquid flow channel of the fish-shaped sheet liquid damper.

[0008] Preferably, the fish-shaped sheet liquid damper is at least one of the following structures or a combination of two or more: no filler in the flow channel, mesh plate disturbing body in the flow channel, and porous material damping filler in the flow channel.

[0009] Preferably, the guide partition plates are arranged in a staggered manner along the chord direction of the fish-shaped sheet liquid damper; one end of the guide partition plate is connected to the PS surface fish shell of the closed fish-shaped shell of the fish-shaped sheet liquid damper, and a gap is reserved between the other end and the SS surface fish shell of the closed fish-shaped shell of the fish-shaped sheet liquid damper, or a gap is reserved between one end of the guide partition plate and the PS surface fish shell of the closed fish-shaped shell of the fish-shaped sheet liquid damper, and the other end is connected to the SS surface fish shell of the closed fish-shaped shell of the fish-shaped sheet liquid damper.

[0010] Preferably, the chord-wise spacing between adjacent flow guide partition plates is in the range of 15-50 mm, that is, the size of the damping liquid flow channel in the fish-shaped sheet liquid damper is in the range of 15-50 mm.

[0011] Preferably, the fish-shaped sheet liquid damper has a closed fish-shaped housing made of glass fiber reinforced resin composite material.

[0012] Preferably, the guide partition plate is a glass fiber reinforced resin composite material partition plate.

[0013] Preferably, the size of the damping liquid flow channel in the fish-shaped sheet liquid damper is in the range of 15-50 mm.

[0014] Preferably, the volume filling rate of the damping liquid in the fish-shaped sheet liquid damper is in the range of 20%-30%, the viscosity of the damping liquid is in the range of 1-100 centipoise, and the liquid filling amount is in the range of 2-5 kg.

[0015] Preferably, the length of the fish-shaped sheet liquid damper from the fish head to the fish tail is in the range of 600-1000 mm.

[0016] Preferably, the fish head and the fish tail of the fish-shaped plate-type liquid damper correspond to the leading edge and the trailing edge positions of the blade respectively.

[0017] The present invention also provides a method for preparing the wind turbine blade equipped with the liquid damper, comprising the following steps:

[0018] Prefabricate a fish-shaped sheet-type liquid damper and inject damping liquid;

[0019] Prefabricated blade SS half shells, PS half shells and blade webs;

[0020] Place the blade web and the fish-shaped sheet liquid damper in the SS half shell, and fix the various components with structural adhesive, and apply structural adhesive on the joint surface of the fish-shaped sheet liquid damper that will be bonded to the blade PS surface skin;

[0021] The PS half shell is turned over to the SS half shell for closing the mold, and the outer shell of the fish-shaped sheet liquid damper and the blade skin are bonded together by structural adhesive;

[0022] The structural adhesive is cured and the bonding of the two half shells is completed to obtain a wind turbine blade equipped with a liquid damper.

[0023] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0024] 1. This type of wind turbine blade equipped with a fish-shaped liquid damper can effectively reduce vibration, increase the fatigue life of the blade, prevent resonance, and avoid blade breakage accidents.

[0025] 2. Compared with blades equipped with eddy current tuned mass dampers, liquid dampers have the advantages of lifetime maintenance-free and low cost. They can be installed close to the blade tip, and installing them at the blade tip can greatly improve the damping efficiency of the blade.

[0026] 3. This fish-shaped sheet liquid damper is different from the U-shaped tuned liquid damper. Its biggest advantage is that it is not affected by the different phase postures of the blades when rotating in the air.

[0027] 4. The blades equipped with the fish-shaped liquid damper can effectively suppress the vibration of the blades in the swing direction when the blades are running, stopped and idling. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural diagram of a single fish-shaped sheet liquid damper configured at the blade tip section.

[0029] Figure 2 This is a configuration diagram of an axially series array of 15 fish-shaped sheet liquid dampers.

[0030] Figure 3 It is one of the structural forms of the fish-shaped sheet liquid damper (called form A).

[0031] Figure 4 It is the second structural form of the fish-shaped sheet liquid damper (called form B).

[0032] Figure 5 It is the third structural form of the fish-shaped sheet liquid damper (called form C). DETAILED DESCRIPTION

[0033] The present invention is further described in detail below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0034] like Figure 1 and Figure 2 As shown, this embodiment discloses a wind turbine blade equipped with a liquid damper. In a section 10-20m away from the blade tip, N fish-shaped sheet liquid dampers 1 are arranged in series along the axial direction of the blade inner cavity, N is 10-20, and the two fish-shaped sheet liquid dampers 1 are stacked in a sheet-like manner. Along the span direction of the blade, the shape and size of each fish-shaped sheet liquid damper 1 are consistent with the inner cavity space of the section, so as to be adapted and embedded in the inner cavity of the blade. The N fish-shaped sheet liquid dampers 1 are equivalent to replacing the original blade web in the section; the fish-shaped sheet liquid damper 1 and the blade skin 5 and the two fish-shaped sheet liquid dampers 1 are used between The fish-shaped sheet liquid damper 1 is a sheet prefabricated part with a fish-shaped cross-section and a thickness of 50-150mm. Its outer contour is the clearance size of the inner cavity of the blade airfoil section. In order to exert the damping effect, the fish-shaped sheet liquid damper 1 must provide a maximum flow to increase the damping effect. Therefore, the interior of the fish-shaped sheet liquid damper 1 is provided with a guide partition plate 11 perpendicular to the blade chord line. The guide partition plate 11 divides the inner cavity of the fish-shaped sheet liquid damper 1 into a tortuous and elongated damping liquid flow channel to extend the flow length of the damping liquid from the leading edge to the trailing edge of the blade. The flow channel size is in the range of 15-50mm.

[0035] This fish-shaped sheet liquid damper 1 is to eliminate the influence of the huge centrifugal force at the blade tip position on the damping effect. Therefore, the dimension of the damper along the blade span length direction, called the fish-sheet thickness, cannot be too large and is in the range of 50mm-150mm.

[0036] To achieve standardized design, the length of the fish-shaped sheet liquid damper 1 from the fish head to the fish tail is determined in a specification series within the range of 600-1000 mm, such as 600 mm, 700 mm, 800 mm, and so on.

[0037] In addition, the fish-shaped sheet-type liquid damper 1 can also be filled with spoiler or damping materials, such as mesh plates or porous materials, according to requirements.

[0038] In each fish-shaped sheet liquid damper 1, the volume filling rate of the damping liquid is in the range of 20%-30%, and the viscosity of the damping liquid is in the range of 1-100 centipoise. The damper made in this way has a liquid filling amount of 2-5kg. If the blade requires a total amount of 50kg of damping liquid, the standard damper needs to be configured in series with 10-20 fish-shaped sheet liquid dampers 1 along the blade span. First of all, a comprehensive decision should be made based on the structural essentials of the liquid damper combined with the specific spatial position of the blade tip section installation. In the blade tip section, there is a trade-off balance of the installation position. On the one hand, the damper requires as high a motion stroke as possible, so it is determined that the damper must be installed far away from the blade tip to have a larger chord length space. On the other hand, the closer the damper is to the blade tip, the smaller the modal mass of the blade and the stronger the damping capacity. Therefore, it has been verified by experiments that it is more reasonable for the damper of the present invention to be located in a section 10-20m away from the blade tip.

[0039] The fish head and fish tail of the fish-shaped sheet liquid damper 1 correspond to the leading edge 3 and trailing edge 2 of the blade, respectively. The blade web 4 is an important shear-bearing structure of the "I"-shaped main beam of the blade. It is fixed at about 1 / 3 of the blade chord line. The blade web 4 is connected to the PS beam cap and SS beam cap of the blade, perpendicular to the PS and SS airfoil surfaces of the blade. In order to install the fish-shaped sheet liquid damper 1, it is necessary to cut the blade web 4. For this purpose, the closed fish-shaped shell 6 and the guide partition plate 11 of the fish-shaped sheet liquid damper 1 must be able to equivalently replace the role of the blade web 4. Therefore, the closed fish-shaped shell 6 and the guide partition plate 11 of the fish-shaped sheet liquid damper 1 are both glass fiber reinforced plastic composite materials, and in this embodiment, they are specifically glass fiber reinforced resin composite materials, which play both the role of a container and the role of a web. The shell contour of the fish-shaped sheet liquid damper 1 has a curved contour that follows the blade airfoil, which is equivalent to being adapted and embedded in the inner cavity of the blade. Its specific contour size only needs to subtract the thickness of the blade skin 5. The fish-shaped sheet-type liquid damper 1 and the blade skin 5 are bonded into a whole by using structural adhesive.

[0040] Usually, the damping of the blade requires a certain amount of liquid mass, such as 50kg of damping liquid. However, the damper installed near the tip of the blade has limited volume space of the blade, and the damper must have limited volume. A single liquid damper can usually only be configured with about 3kg of damping liquid, which means that multiple liquid dampers, such as 15, are required. In order to improve the efficiency of the configuration space, the liquid damper is made into a fish-shaped sheet structure, that is, the damper has two parallel shell planes, and the thickness is in the range of 50-150mm. The thickness dimension is small relative to the length of the fish-shaped profile of about 800mm, so it is described as a fish-shaped sheet structure. When the damper is installed, the projection surface of the fish-shaped profile is perpendicular to the span direction of the blade, and the thickness of the fish slice is along the span direction of the blade. Figure 2This is the effect diagram of 15 fish-shaped sheet liquid dampers 1 being integrated in series along the blade span direction, so that the total damping liquid mass reaches 50kg. The sheet planes of adjacent dampers are contacted in sequence and bonded together by structural adhesive.

[0041] If the length of the integrated body of 15 fish-shaped plate-type liquid dampers 1 is 15×0.1m, it means that the blade web 4 must be cut off by a corresponding length value, and the damper integrated body will completely replace the missing web.

[0042] The technical solution of integrating a single small liquid damper is adopted, and the damper needs to be designed in a standardized series, and as few specifications as possible can cover the use of all capacity blades. The present invention recommends the use of three specifications of fish-shaped sheet liquid dampers 1 with a length from the head to the tail of 600, 700, and 800 mm.

[0043] In summary, the structure of the damper and the structure of the blade are essentially integrated into one design and have high structural efficiency.

[0044] The above-mentioned attached examples only illustrate the spatial geometric configuration between the damper and the blade and the integrated design scheme. As a technical solution for blade vibration damping, the second design link is the internal structure scheme of how the fish-shaped sheet liquid damper 1 plays a damping role.

[0045] Figure 3 In the example of a fish-shaped sheet liquid damper, if the interior is completely empty, when the blade oscillates along the chord direction, the damping liquid reciprocates between the fish head and the fish tail, and the ability to damp and dissipate the vibration kinetic energy is limited, and the damping effect is poor. For this reason, a flow channel with a specific flux is provided in the damper to increase the flow length of the damping liquid. The flow channel is composed of a group of guide partition plates 11 arranged in a staggered interval in sequence along the chord direction of the fish-shaped sheet liquid damper 1 to complete the guide partition. The guide partition plates 11 are made of glass fiber reinforced plastic composite materials, and in this embodiment, they are specifically glass fiber reinforced resin composite materials, replacing the blade web 4, and the chord spacing of the guide partition plates 11 is in the range of 15-50mm. One end of the guide partition plate 11 is connected to the PS surface fish shell 9 of the closed fish-shaped shell 6 of the fish-shaped sheet liquid damper 1, and the other end is reserved with a gap between the SS surface fish shell 10 of the closed fish-shaped shell 6 of the fish-shaped sheet liquid damper 1, for example, 15mm. In this way, the damping liquid can flow from one end to the other end in a circuitous manner in the inner cavity of the fish-shaped sheet liquid damper 1, such as flowing in the direction of the arrow shown in the figure. Of course, there is another form, such as a gap is reserved between one end of the guide partition plate 11 and the PS surface fish shell 9 of the closed fish-shaped shell 6 of the fish-shaped sheet liquid damper 1, and the other end is connected to the SS surface fish shell 10 of the closed fish-shaped shell 6 of the fish-shaped sheet liquid damper 1.

[0046] The damper of the present invention is arranged in the swing direction of the blade to damp the vibration in the swing direction of the blade, mainly to damp the first-order swing of the blade. Usually, the first-order swing frequency of large blades is about 0.5Hz. When the blade swings and vibrates, the mass inertia of the damping fluid tends to keep the damping fluid in place, but the guide partition plate 11 in the damper that moves with the blade vibration will inevitably push the liquid mass to shift and do work. When the liquid shifts and flows, the transverse guide partition plate 11 will block the flow of the liquid, and through the effects of liquid turbulence, surface tension, etc., it will dissipate the kinetic energy brought to the damping fluid by the blade vibration. Thereby, the blade vibration damping effect is achieved.

[0047] Figure 4 The fish-shaped liquid damper of the example is compared with Figure 3 The damper is just equipped with a built-in flow channel mesh plate 12 in the flow, and the damping fluid flowing through the flow channel mesh plate 12 will produce a greater damping force. Other structural features are similar and will not be repeated.

[0048] Figure 5 The fish-shaped liquid damper of the example is compared with Figure 3 The damper is just filled with a built-in porous material 13, and the damping fluid flowing through the porous material 13 will produce a greater damping force. Other structural features are similar and will not be repeated.

[0049] Figure 3 , 4 In , 5, the fish-shaped outer contour line 7 of the damper is due to the inner contour of the blade cavity obtained by following the blade airfoil curve. The PS surface fish shell 9 is obtained corresponding to the inner wall surface of the PS surface skin of the blade airfoil, and the SS surface fish shell 10 is obtained corresponding to the inner wall surface of the SS surface skin of the blade airfoil.

[0050] Figure 3 , 4 , 5, are all fish-shaped sheet liquid dampers, the damper has two parallel sheet planes 8, and the more practical fish sheet thickness range is 50-150mm.

[0051] Figure 3 , 4 In , 5, three damper structure embodiments are enumerated. A blade can be configured with any one or more combinations of fish-shaped sheet liquid damper structures A, B, and C.

[0052] The following is a method for preparing the wind turbine blade equipped with the liquid damper in this embodiment, comprising the following steps:

[0053] Prefabricate a fish-shaped sheet-type liquid damper 1 and inject damping liquid;

[0054] Prefabricated blade SS half shells, PS half shells and blade webs;

[0055] The blade web and the fish-shaped sheet liquid damper 1 are placed in the SS half shell, and the various components are bonded and fixed with structural adhesive, and the structural adhesive is applied on the joint surface of the fish-shaped sheet liquid damper 1 to be bonded with the blade PS surface skin;

[0056] The PS half shell is turned over to the SS half shell for closing the mold, and the outer shell of the fish-shaped sheet liquid damper 1 and the blade skin 5 are contacted and bonded together by structural adhesive;

[0057] The structural adhesive is cured and the bonding of the two half shells is completed to obtain a wind turbine blade equipped with a liquid damper.

[0058] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A wind turbine blade equipped with a liquid damper, characterized in that: In a section 10-20 m away from the blade tip, N fish-shaped sheet-type liquid dampers (1) are arranged in series along the axial direction of the blade inner cavity, N being 10-20, and the two fish-shaped sheet-type liquid dampers (1) are stacked in a sheet-like manner, and arrayed along the span direction of the blade. The shape and size of each fish-shaped sheet-type liquid damper (1) is consistent with the inner cavity space of the section, so as to be adapted and embedded in the inner cavity of the blade. The N fish-shaped sheet-type liquid dampers (1) are equivalent to replacing the original blade belly plate in the section; between the fish-shaped sheet-type liquid damper (1) and the blade skin (5), and between the two fish-shaped sheet-type liquid dampers (1). The fish-shaped sheet-type liquid dampers (1) are bonded together with structural adhesive; the fish-shaped sheet-type liquid damper (1) is a sheet-type prefabricated part with a fish-shaped cross-section, with a thickness of 50-150 mm, and its outer contour is the inner cavity clearance size of the blade airfoil cross-section; the fish-shaped sheet-type liquid damper (1) is provided with a guide partition plate (11) perpendicular to the blade chord line inside, and the guide partition plate (11) divides the inner cavity of the fish-shaped sheet-type liquid damper (1) into a tortuous and elongated damping liquid flow channel, so as to extend the flow length of the damping liquid from the leading edge to the trailing edge of the blade.

2. A wind turbine blade equipped with a liquid damper according to claim 1, characterized in that: A disturbing fluid or a porous material damping filling body is provided in the damping liquid flow channel of the fish-shaped sheet-type liquid damper (1).

3. A wind turbine blade equipped with a liquid damper according to claim 1, characterized in that: The fish-shaped sheet-type liquid damper (1) is at least one of three structures, or a combination of two or more structures, including no filler in the flow channel, a mesh plate disturbing body in the flow channel, and a porous material damping filler in the flow channel.

4. A wind turbine blade equipped with a liquid damper according to claim 1, characterized in that: The flow guide partition plates (11) are arranged in a staggered manner in sequence along the chord direction of the fish-shaped plate-type liquid damper (1); one end of the flow guide partition plate (11) is connected to the PS surface fish shell (9) of the closed fish-shaped shell (6) of the fish-shaped plate-type liquid damper (1), and a gap is reserved between the other end and the SS surface fish shell (10) of the closed fish-shaped shell (6) of the fish-shaped plate-type liquid damper (1); or one end of the flow guide partition plate (11) is reserved with a gap between the PS surface fish shell (9) of the closed fish-shaped shell (6) of the fish-shaped plate-type liquid damper (1), and the other end is connected to the SS surface fish shell (10) of the closed fish-shaped shell (6) of the fish-shaped plate-type liquid damper (1).

5. A wind turbine blade equipped with a liquid damper according to claim 4, characterized in that: The chord-wise spacing between adjacent flow guide partition plates (11) is in the range of 15-50 mm, that is, the size of the damping liquid flow channel in the fish-shaped sheet liquid damper (1) is in the range of 15-50 mm.

6. A wind turbine blade equipped with a liquid damper according to claim 1, characterized in that: The fish-shaped sheet-type liquid damper (1) has a closed fish-shaped shell (6) made of glass fiber reinforced resin composite material, and the flow guide partition plate (11) is a glass fiber reinforced resin composite material partition plate.

7. A wind turbine blade equipped with a liquid damper according to claim 1, characterized in that: The volume filling rate of the damping liquid in the fish-shaped sheet-type liquid damper (1) is in the range of 20%-30%, the viscosity of the damping liquid is in the range of 1-100 centipoise, and the liquid filling amount is in the range of 2-5 kg.

8. The wind turbine blade equipped with a liquid damper according to claim 1, characterized in that: The length of the fish-shaped sheet-type liquid damper (1) from the fish head to the fish tail is in the range of 600-1000 mm.

9. The wind turbine blade equipped with a liquid damper according to claim 1, characterized in that: The fish head and the fish tail of the fish-shaped sheet-type liquid damper (1) correspond to the leading edge (3) and the trailing edge (2) positions of the blade respectively.

10. The method for preparing a wind turbine blade according to any one of claims 1 to 9, characterized in that: The following steps are involved: Prefabricate a fish-shaped sheet-type liquid damper (1) and inject damping liquid; Prefabricated blade SS half shells, PS half shells and blade webs; The blade web and the fish-shaped sheet-type liquid damper (1) are placed in the SS half shell, and the various components are bonded and fixed with structural adhesive, and the structural adhesive is coated on the joint surface of the fish-shaped sheet-type liquid damper (1) to be bonded with the PS surface skin of the blade; The PS half shell is turned over to the SS half shell for closing the mold, and the outer shell of the fish-shaped sheet liquid damper (1) and the blade skin (5) are contact-bonded together by means of structural adhesive; The structural adhesive is cured and the bonding of the two half shells is completed to obtain a wind turbine blade equipped with a liquid damper.

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