Blade of vertical-axis wind turbine and vertical-axis wind turbine

Abstract

A blade of a vertical axis wind turbine comprises a blade body, the blade body is in a wing shape, and a plurality of grooves are formed in the side wall of the blade body at intervals. According to the blade of the vertical-axis wind driven generator and the vertical-axis wind driven generator, the grooves are formed in the side wall of the blade body, the blade body is installed between the upper support and the lower support, the grooves are axially formed, in the starting stage, when wind blows through the surface of the blade with sawteeth, air rushes into the grooves, the grooves serve as wind catching devices, the wind catching area is increased, and the wind catching effect is improved. Large driving force is generated; when wind passes through the sawtooth-shaped blades, the turbulence degree of airflow can be increased through the design of the grooves, the acting time and stroke of the airflow on the surfaces of the blades are further increased, and therefore resistance is improved, and generation of enough starting torque is facilitated. When the wind turbine runs, the direction of the groove can be along the airflow direction when the wind turbine rotates, the attached flow of the wing shape is not damaged, the lift-drag ratio of the wing shape is not reduced, and the aerodynamic efficiency of the wind turbine can be well guaranteed.

Description

Technical Field

[0001] The present invention relates to a blade of a vertical-axis wind turbine and a vertical-axis wind turbine. Background Art

[0002] In recent years, with the increasing global attention to renewable energy and environmental protection technologies, wind power generation, as a clean energy source, has developed rapidly. Although traditional horizontal-axis wind turbines have been widely used, they have certain deficiencies in terms of installation sites, wind speed adaptability, and maintenance costs. Vertical-axis wind turbines, due to their unique designs and advantages, have gradually received attention.

[0003] The advantages of vertical-axis wind turbines are as follows: 1. They have good wind direction adaptability, are not affected by wind direction changes, and can operate stably under various wind speed conditions; 2. The structure is relatively simple; 3. They occupy less space and are suitable for applications in cities and complex environments; 4. Ground maintenance is convenient; 5. The noise is relatively low, which helps to reduce interference with the surrounding environment. However, the biggest weakness of vertical-axis lift-type wind turbines is poor starting performance and high cut-in wind speed. Regarding the poor starting performance, the key technical problems are: low starting efficiency at low wind speeds, insufficient starting torque, and aerodynamic design limitations. To address this shortcoming, there are also many improved vertical-axis wind turbines on the market, such as designing airfoil openings at the front end of the blade, combining lift and drag designs, or using spiral blade designs; these designs have improved the starting torque to a certain extent, but have also significantly reduced the power output.

[0004] This patent aims to propose a new type of vertical-axis wind turbine airfoil, aiming to improve the starting performance of lift-type vertical-axis wind turbines, reduce the cut-in wind speed, and ensure the aerodynamic efficiency during the operation of the wind turbine to achieve starting under low-wind conditions and efficient power generation, better meeting the future demand for clean energy. Summary of the Invention

[0005] The present invention provides a blade of a vertical-axis wind turbine and a vertical-axis wind turbine.

[0006] The technical solution adopted by the present invention to solve the above technical problems is as follows:

[0007] A blade of a vertical-axis wind turbine, comprising a blade body. The blade body is an airfoil, and a plurality of grooves are spacedly arranged on the side wall of the blade body, and the grooves form a serrated structure on the blade body.

[0008] Preferably, the blade body is a straight blade or a curved blade.

[0009] Preferably, the blade body is formed by pultrusion or injection molding.

[0010] Preferably, the grooves are provided on both the front and the back.

[0011] Preferably, the whole of the groove is close to the leading edge of the blade body.

[0012] Preferably, the shape of the groove is rectangular.

[0013] Preferably, the direction of the groove faces the leading edge of the blade body.

[0014] Preferably, the shape of the groove is triangular.

[0015] A vertical-axis wind turbine, characterized in that it comprises a base and a generator arranged below the base, a main shaft passing through the base is arranged on the generator, a plurality of brackets arranged at intervals are arranged on the circumferential side of the main shaft, the brackets include an upper bracket and a lower bracket which are opposite up and down, blades are fixedly arranged on the upper bracket and the lower bracket, the top surface and the bottom surface of the blade body are respectively connected with the upper bracket and the lower bracket, and the groove is arranged axially.

[0016] Preferably, the number of the brackets is 2-5.

[0017] Compared with the prior art, for the blade of the vertical-axis wind turbine of the present invention and the vertical-axis wind turbine, by arranging a plurality of grooves on the side wall of the blade body, the blade body is installed between the upper bracket and the lower bracket, and the grooves are arranged axially. In the starting stage, when the wind blows over the serrated blade surface, the air rushes into the grooves and acts as a wind-catching device, increasing the wind-catching area and generating a greater driving force on the blade body; when the wind passes through the serrated blade, the design of the grooves can also increase the turbulence of the air flow, further increasing the acting time and travel of the air flow on the blade surface, thereby increasing the resistance and helping to generate sufficient starting torque. When the wind turbine is running, the direction of the grooves can follow the air flow direction when the wind turbine rotates, without destroying the attached flow of the airfoil and not reducing the lift-drag ratio of the airfoil, and can preferably ensure the aerodynamic efficiency of the wind turbine. The vertical-axis wind turbine of the present invention has the characteristics of low-wind-speed starting and high aerodynamic efficiency. Description of the Drawings

[0018] Figure 1 It is a three-dimensional schematic diagram of Embodiment 1 of the blade of the vertical-axis wind turbine of the present invention.

[0019] Figure 2 It is a top view of Embodiment 1 of the blade of the vertical-axis wind turbine of the present invention.

[0020] Figure 3 It is a top view of Embodiment 2 of the blade of the vertical-axis wind turbine of the present invention.

[0021] Figure 4 It is a top view of Embodiment 3 of the blade of the vertical-axis wind turbine of the present invention.

[0022] Figure 5 This is a partial schematic view of the vertical-axis wind turbine of the present invention. Specific embodiments

[0023] The present invention will be further described in detail below in conjunction with the embodiments with reference to the drawings.

[0024] Embodiment 1:

[0025] As Figure 1-2 shown, a blade of a vertical-axis wind turbine includes a blade body 1. The blade body 1 is an airfoil shape. The blade body 1 can be a straight blade or a curved blade. A plurality of grooves 2 are arranged at intervals on the side wall of the blade body 1, and the plurality of grooves 2 form a serrated structure on the blade body 1; the grooves 2 can be arranged on one side of the side wall of the front or back surface of the blade body 1, or on both sides of the front and back surfaces. The number and size of the grooves 2 are not limited, and the shape of the grooves 2 is not limited, and can be rectangular or triangular, etc.; the orientation of the grooves 2 faces the leading edge of the blade body 1; the position of the grooves 2 is also not limited, and can be close to the leading edge of the blade body 1 or close to the trailing edge of the blade body 1. In this embodiment, the grooves 2 are arranged on both the front and back surfaces and are overall close to the leading edge of the blade body 1. The shape of the grooves 2 is rectangular and the orientation faces the leading edge of the blade body 1.

[0026] Embodiment 2:

[0027] As Figure 3 shown, the shape of the groove 2 is triangular and the orientation faces the leading edge of the blade body 1. The grooves 2 are arranged on both sides of the blade body 1 and the number on one side is 4.

[0028] Embodiment 3:

[0029] As Figure 4 shown, the shape of the groove 2 is triangular and the orientation faces the leading edge of the blade body 1. The groove 2 is only arranged on one side of the blade body 1 and the number of the grooves 2 is 4.

[0030] The blade body 1 of the straight blade is formed by pultrusion process, which not only has fast forming speed but also good quality.

[0031] The blade body 1 of the curved blade is formed by injection molding.

[0032] As Figure 5As shown in the figure, a vertical axis wind turbine includes a base 3 and a generator 4 disposed below the base 3. A main shaft 41 passing through the base 3 is provided on the generator 4. A plurality of brackets 5 spaced apart are provided on the circumferential side of the main shaft 41. The number of brackets 5 is 2 - 5. In this embodiment, the number of brackets 5 is three. The bracket 5 includes an upper bracket 51 and a lower bracket 52 which are opposite to each other up and down. A blade body 1 is fixedly provided on the upper bracket 51 and the lower bracket 52. The top surface and the bottom surface of the blade body 1 are respectively connected to the upper bracket 51 and the lower bracket 52, and the groove 2 is axially provided. The groove 2 can act as a wind-catching device at startup to increase the wind-catching area and generate a greater driving force on the blade body. During operation, since the groove 2 is along the running direction, it does not disrupt the attached flow of the airfoil and does not reduce the lift-to-drag ratio of the airfoil, which can better ensure the aerodynamic efficiency of the wind turbine. Due to the difference in the work capacity of the vertical axis wind turbine blades at different circumferential phase angles, when the leading edge of the blade is in the windward position, the air flow can maintain a good attached flow, and the serrated structure will not have a negative impact on its aerodynamic performance. When the trailing edge of the blade is in the windward position, the presence of the serrated groove enhances the wind-catching ability of the blade, thereby increasing the circumferential driving force of the blade. Therefore, although the aerodynamic shape of the serrated blade is mainly a lift-type airfoil, after being applied to a vertical axis wind turbine, it has the characteristics of both lift and drag combination.

[0033] In the vertical axis wind turbine of the present invention, the blade and the vertical axis wind turbine are provided with a plurality of grooves 2 on the side wall of the blade body 1. The blade body 1 is installed between the upper bracket 51 and the lower bracket 52, and the groove 2 is axially provided. When the wind blows over the serrated blade surface, the air rushes into the groove 2, which can generate a greater driving force on the blade body 1. In the startup stage, when the wind blows over the serrated blade surface, the air rushes into the groove 2, acting as a wind-catching device, increasing the wind-catching area, and generating a greater driving force on the blade body 1. When the wind passes through the serrated blade, the design of the groove 2 can also increase the turbulence of the air flow, further increasing the action time and travel of the air flow on the blade surface, thereby increasing the resistance and helping to generate sufficient starting torque. When the wind turbine is running, the direction of the groove 2 can follow the air flow direction when the wind turbine rotates, without disrupting the attached flow of the airfoil and not reducing the lift-to-drag ratio of the airfoil, which can better ensure the aerodynamic efficiency of the wind turbine. The vertical axis wind turbine of the present invention has the characteristics of low wind speed startup and high aerodynamic efficiency.

[0034] Finally, it should be noted that the above embodiments only illustrate the technical solutions of the present invention and do not limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments or perform equivalent replacements for some of the technical features. And these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A blade for a vertical axis wind turbine, comprising a blade body (1), characterized in that: The blade body (1) is an airfoil-shaped blade, and a plurality of grooves (2) are arranged at intervals on the side wall of the blade body (1), wherein the grooves (2) form a sawtooth structure on the blade body (1).

2. The blade of the vertical axis wind turbine according to claim 1, characterized in that: The blade body (1) is a straight blade or a curved blade.

3. The blade of the vertical axis wind turbine according to claim 2, characterized in that: The blade body (1) is formed by pultrusion or injection molding.

4. The blade of the vertical axis wind turbine according to claim 1, characterized in that: The groove (2) is arranged on both the front and back sides.

5. The blade of the vertical axis wind turbine according to claim 1, characterized in that: The groove (2) is entirely close to the leading edge of the blade body (1).

6. The blade of the vertical axis wind turbine according to claim 1, characterized in that: The groove (2) is in the shape of a rectangle.

7. The blade of the vertical axis wind turbine according to claim 1, characterized in that: The groove (2) is directed toward the leading edge of the blade body (1).

8. The blade of the vertical axis wind turbine according to claim 1, characterized in that: The groove (2) is in the shape of a triangle.

9. A vertical axis wind turbine, characterized in that: The invention comprises a base (3) and a generator (4) arranged below the base (3); the generator (4) is provided with a main shaft (41) penetrating the base (3); a plurality of brackets (5) arranged at intervals are arranged on the circumferential side of the main shaft (41); the brackets (5) comprise an upper bracket (51) and a lower bracket (52) opposite to each other in upper and lower directions; the upper bracket (51) and the lower bracket (52) are fixedly provided with blades according to any one of claims 1 to 8; the top surface and the bottom surface of the blade body (1) are respectively connected to the upper bracket (51) and the lower bracket (52); and the groove (2) is arranged axially.

10. The vertical axis wind turbine according to claim 9, characterized in that: The number of the brackets (5) is 2-5.

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