阅读说明：本技术 一种用于中低风速的风机叶片 (Fan blade for medium and low wind speed ) 是由 王恩民 任鑫 王剑钊 童彤 王晨 王�华 杨晓峰 赵鹏程 于 2019-11-19 设计创作，主要内容包括：本发明提供的一种用于中低风速的风机叶片,包括原风机叶片本体、叶尖延长部和格林襟翼,其中,原风机叶片本体包括叶根部和叶片中部,其中,叶片中部的一端与叶根部连接,另一端与叶片叶尖延长部连接,所述格林襟翼安装在叶片叶尖延长部上；本发明通过格林襟翼用以实现对叶片尖端附近流场进行优化控制,达到提升叶片升阻比,协调和改善叶片气动特性的目的；同时,能够增加和改善叶片的捕风能力,从而提高风机在中低风速区域的发电能力。(The invention provides a fan blade for medium and low wind speeds, which comprises an original fan blade body, a blade tip extension part and a Green flap, wherein the original fan blade body comprises a blade root part and a blade middle part, one end of the blade middle part is connected with the blade root part, the other end of the blade middle part is connected with the blade tip extension part, and the Green flap is arranged on the blade tip extension part; according to the invention, the Green flap is used for realizing optimized control of the flow field near the tip of the blade, so that the purposes of improving the lift-drag ratio of the blade and coordinating and improving the aerodynamic characteristics of the blade are achieved; meanwhile, the wind catching capacity of the blades can be increased and improved, so that the power generation capacity of the fan in a medium-low wind speed area is improved.)

1. The utility model provides a fan blade for well low wind speed, its characterized in that includes former fan blade body (1), apex extension (3) and green wing flap (4), wherein, former fan blade body (1) includes root of blade portion and blade middle part, and wherein, the one end and the root of blade portion in blade middle part are connected, and the other end is connected with blade apex extension (3), green wing flap (4) are installed on blade apex extension (3).

2. The fan blade for medium and low wind speed according to claim 1, wherein the structure of the blade tip extension part (3) is the same as that of the original blade tip (2), and a mounting groove is formed in the tail edge of the lower surface of the blade tip extension part and arranged along the length direction of the fan blade; the Green flap (4) is arranged in the mounting groove.

3. A fan blade for medium and low wind speeds according to claim 2, characterised in that the green flap (4) is fixed at both ends to both side walls of the mounting slot by means of mechanical shaft parts (5).

4. A fan blade for medium and low wind speeds according to claim 1, characterized in that the green flap (4) is of a rectangular flat plate structure.

5. The fan blade for medium and low wind speeds according to claim 1, wherein the blade tip extension (3) is connected with one end of the blade middle part of the original fan blade body (1) through an adhesive.

6. A fan blade for medium and low wind speeds according to claim 1, characterised in that the length of the blade tip extension (3) is less than or equal to 10% of the original blade length.

Technical Field

The patent relates to the technical field of wind power generation, in particular to a fan blade for medium and low wind speed.

Background

At present, the market of the wind power industry in high wind speed wind areas in China is basically developed. The medium and low wind speed wind area becomes a new investment focus in the wind power industry. The medium-low wind speed wind resource area is generally close to a city and a population density area, so that the method has the advantages of being close to a load center, convenient to grid connection, small in influence on power grid dispatching operation and the like, and has development potential. But because the wind resource is relatively poor, the wind energy conversion efficiency is low, the investment recovery period is long, and the development of the wind energy conversion system is greatly restricted. In order to solve the problem, the coping method in the market at present generally adopts a mode of lengthening blades or increasing the height of a tower, and the methods have the problems of increased weight of a fan, increased cost, influenced unit safety and the like.

Aiming at the actual wind resource condition of medium and low wind speed, the invention adopts a mode of prolonging the blade tip length of the blade and increasing the Green flap at the blade tip to change the airfoil shape of the blade, optimize the aerodynamic force of the blade, improve the lift-drag ratio, improve the capability of effectively capturing wind energy of the wind generating set and improve the wind energy conversion efficiency.

Disclosure of Invention

The invention aims to provide a fan blade for medium and low wind speeds, and overcomes the defects of high cost and poor safety of wind power generation in the existing medium and low wind speed wind resource area.

In order to achieve the purpose, the invention adopts the technical scheme that:

the invention provides a fan blade for medium and low wind speeds, which comprises an original fan blade body, a blade tip extension part and a Green flap, wherein the original fan blade body comprises a blade root part and a blade middle part, one end of the blade middle part is connected with the blade root part, the other end of the blade middle part is connected with the blade tip extension part, and the Green flap is installed on the blade tip extension part.

Preferably, the structure of the blade tip extension part is the same as that of the original blade tip, and a mounting groove is formed in the tail edge of the lower surface of the blade tip extension part and arranged along the length direction of the fan blade; the green flap is disposed within the mounting slot.

Preferably, both ends of the green flap are fixed on both side walls of the mounting groove by mechanical shaft parts.

Preferably, the green flap is of a rectangular flat plate construction.

Preferably, the blade tip extension part is connected with one end of the blade middle part of the original fan blade body through an adhesive.

Preferably, the length of the blade tip extension part is less than or equal to 10% of the original blade length.

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

according to the fan blade for medium and low wind speeds, the wind sweeping area is increased by prolonging the blade tip part of the blade; a Green wing flap is additionally arranged, so that the lift force of the blade is improved, the lift-drag ratio of the blade is improved, the blade profile is improved, and the formation of vortex is improved; the structure of the invention can increase a small amount of materials under the condition of keeping the main structure of the original fan blade, thereby improving the wind catching efficiency of the blade to the maximum extent and improving the generating capacity of the wind turbine generator; the Green flap is used for realizing the optimized control of the flow field near the tip of the blade, so that the purposes of improving the lift-drag ratio of the blade and coordinating and improving the aerodynamic characteristics of the blade are achieved; the fan blade provided by the invention can increase and improve the wind catching capacity of the blade, so that the power generation capacity of the fan in a medium-low wind speed area is improved.

Drawings

FIG. 1 is a schematic view of a raw fan blade structure;

FIG. 2 is a schematic view of a fan blade configuration to which the present invention relates;

FIG. 3 is a schematic view of the assembly of a blade tip extension and a Green flap;

the device comprises a fan blade body 1, an original fan blade body 2, an original blade tip 3, a blade tip extension part 4, a Green flap 5 and a mechanical shaft part.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

In the actual operation process of the fan blade, under the influence of factors such as an attack angle, blade airfoil profile and thickness, airflow is separated in different degrees after flowing through the front edge, the larger the attack angle is, the greater the separation degree between the airflow and the blade is, so that the operation resistance of the blade is increased, and the wind energy conversion efficiency of the unit is reduced.

In view of the above situation, in order to achieve the purpose of increasing the power of the wind turbine generator in the medium-low wind speed area, the invention provides a fan blade for medium-low wind speed, which is specifically applied to the wind turbine generator with medium-low wind speed area, megawatt level and large blades, especially to the wind turbine generator with power of 1.5MW or above:

as shown in fig. 1 to 3, the fan blade for medium and low wind speeds provided by the present invention includes an original fan blade body 1, an original blade tip 2, a blade tip extension portion 3, and a green flap 4, wherein the original fan blade body 1 includes a blade root portion and a blade middle portion, one end of the blade middle portion is connected to the blade root portion, the other end is connected to the blade tip extension portion 3, and the green flap 4 is installed at the blade tip extension portion 3.

The green flap 4 is arranged at or near the trailing edge of the lower surface of the blade tip extension 3 and along the length of the blade.

The green flap 4 is of a rectangular flat plate structure.

The green flap 4 is connected with the lengthened structural beam of the blade tip extension part 3 through a mechanical shaft part 5.

The structure of the blade tip extension part 3 is the same as that of the original blade tip 2, and a mounting groove is formed in the tail edge of the lower surface of the blade tip extension part 3.

The green wing flap 4 is installed in the mounting groove, and the two ends of the green wing flap 4 are installed on the two side walls of the mounting groove through the mechanical shaft component 5.

The blade tip extension part 3 is connected with one end of the middle part of the blade of the original fan blade body 1 through an adhesive.

The blade tip extension part 3 is of a curved surface structure, and the curved surface structure is composed of a pressure surface and a suction surface.

And the tip pressure surface and the suction surface of the blade tip extension part 3 are respectively attached to the pressure surface and the suction surface of the original fan blade body 1 and are in smooth transition.

The length of the blade tip extension part 3 is less than or equal to 10% of the original blade length.

Because the blade tip extension part 3 is additionally arranged on the original fan blade body 1, and the Green flap 4 is arranged on the blade tip extension part 3, the parameters of the obtained new fan blade, such as the equivalent torsion angle, the equivalent attack angle, the chord length and the like, are changed, and a new aerodynamic shape is formed.

A processing method for a fan blade with medium and low wind speed comprises the following steps:

step 1, cutting off and polishing a blade tip part of an original blade of a fan blade to obtain an original fan blade body 1, wherein the original fan blade body 1 comprises a blade root part and a blade middle part;

and 2, connecting the blade tip extension part 3 at the free end of the middle part of the blade through an adhesive.

The blade tip of the original blade is extended, and meanwhile, a Green flap structure is added at the extended part of the blade tip, so that a new pneumatic appearance is constructed at the tip part of the blade while the blade is extended; the structure can increase a small amount of materials under the condition of keeping the main structure of the original fan blade, so that the wind catching efficiency of the blade is improved to the maximum extent, and the generating capacity of the wind turbine generator is improved; the Green flap is used for realizing the optimized control of the flow field near the tip of the blade, and the purposes of improving the lift-drag ratio of the blade and coordinating and improving the aerodynamic characteristics of the blade are achieved.

The blade tip part of the blade is prolonged, so that the wind sweeping area is increased; and the Green wing flap is additionally arranged, so that the lift force of the blade is improved, the lift-drag ratio of the blade is improved, the blade profile is improved, and the formation of vortex is improved. The production process is similar to that of the traditional blade, and the wind capturing capacity of the blade can be increased and improved, so that the power generation capacity of the fan in a medium-low wind speed area is improved.

The structure can be transformed based on the blade structure during specific implementation, and the production and installation of required pneumatic components can adopt the production process of the original blade. The production of the parts can be realized by adopting the processes of vacuum infusion, lamination and the like, and the installation can be realized by adopting the processes of hand-pasted fiber cloth reinforcement, structural adhesive bonding, putty filling, polishing and the like.