Vertical axis wind turbine driven by side jet flow and application of vertical axis wind turbine
By setting jet slit components with opposite injection directions on the surface of the vertical axis wind turbine blade, using the power provided by the high-pressure cavity and external power source, the wind turbine self-starting under low wind speed conditions and safe deceleration under high wind speed conditions is achieved, and the operation efficiency and safety of wind turbines in different wind speed environments in the prior art are solved.
Patent Information
- Application Number
- CN202510303103.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-14
- Publication Date
- 2025-05-13
AI Technical Summary
The existing vertical axis wind turbines are difficult to start on their own under low wind speed conditions, and lack an effective deceleration mechanism under high wind speed conditions, resulting in limited operational efficiency and safety under different wind speed environments.
The vertical axis wind turbine design is designed with side jet flow drive. By setting jet slit components with opposite injection directions on the surface of the blade and connecting them to the high-pressure cavity, the power provided by the external power source is used to inject boost force at low wind speeds and provide rotational resistance at high wind speeds, thereby achieving self-starting and safe deceleration.
It effectively shortens the self-starting time of the wind turbine and achieves safe deceleration under high wind speed conditions, improving the operating efficiency and safety of the wind turbine under different wind speed environments, similar to a pneumatic brake mechanism.
Smart Images
Figure CN119982324A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of wind turbines, and in particular to a vertical axis wind turbine driven by a side jet flow and applications thereof. Background Art
[0002] At present, the commonly used way of utilizing wind energy is to generate electricity using wind power. The wind blades, the core components of wind turbines, rotate to convert wind energy into mechanical energy, and then convert mechanical energy into electrical energy through connection with generators. The most commonly used wind turbine is the vertical axis wind turbine, among which the vertical axis wind turbine can be divided into lift type and drag type according to the working principle of its blades. The lift type vertical axis wind turbine relies on the lift generated by the blades to drive the rotation. This type of vertical axis wind turbine has the advantages of simple structure, easy maintenance and wind energy conversion without aligning the wind direction. However, since it is difficult to start by itself under low wind speed conditions, this limits the widespread application of lift type vertical axis wind turbines. Since vertical axis wind turbines are usually not equipped with pneumatic braking mechanisms, they must rely on mechanical braking systems to stop rotation. However, emergency mechanical braking under high-speed rotation may cause damage to the shaft structure of the wind turbine, and in severe cases may even cause the collapse of the wind turbine.
[0003] At present, in order to improve the performance of vertical axis wind turbines, most of them improve the flow state on the blade surface, inhibit or delay the separation of its surface boundary layer, thereby improving the lift-to-drag ratio of the blade and enhancing its self-starting performance, such as active methods such as variable pitch control and plasma excitation and passive methods such as trailing edge flaps and blade surface pits. However, these methods can only improve the self-starting performance of vertical axis wind turbines, but cannot improve the performance of vertical axis wind turbines in effectively reducing speed under high wind speed conditions.
[0004] Therefore, developing a technology that is simple and practical and can enhance the self-starting ability of lift-type vertical-axis wind turbines at low wind speeds and safely decelerate to a stop at high wind speeds in a changing wind speed environment is crucial to improving the engineering application value of such wind turbines and ensuring their safe operation. Summary of the invention
[0005] The object of the present invention is to provide a vertical axis wind turbine driven by a side jet flow and applications thereof.
[0006] As a first aspect of the present invention, the present invention provides a side jet-driven vertical axis wind turbine, comprising a blade, a jet slit assembly with opposite jet directions is arranged near the trailing edge of the blade surface, a high-pressure cavity connected to the jet slit assembly is arranged inside the blade, and the high-pressure cavity is connected to an external power source;
[0007] When starting is required, the power supplied by the external power source is ejected from the forward jet slit assembly through the high-pressure cavity to provide starting power for the blades; when deceleration is required, the power supplied by the external power source is ejected from the reverse jet slit assembly through the high-pressure cavity to provide resistance for the blades.
[0008] According to the present invention, further, the jet slit assembly includes a first jet slit and a second jet slit arranged along the length direction of the blade, and the jet directions of the first jet slit and the second jet slit are opposite; when starting is required, the jet flows out from the first jet slit to provide power to the blade; when deceleration is required, the jet flows out from the second jet slit to provide resistance to the blade.
[0009] According to the present invention, further, a first high-pressure air cavity and a second high-pressure air cavity in contact therewith are provided inside the blade, and the upper and lower ends of the first high-pressure air cavity are respectively connected to the first jet slit on the corresponding side, and the upper and lower ends of the second high-pressure air cavity are respectively connected to the second jet slit on the corresponding side.
[0010] According to the present invention, further, the distance between the intersection surface of the first high-pressure air cavity and the second high-pressure air cavity and the trailing edge is 15%c, wherein c is the chord length.
[0011] According to the present invention, further, the upper and lower surfaces of the blade are both provided with a first jet slit and a second jet slit.
[0012] According to the present invention, further, the first jet slit and the second jet slit are respectively 45° and 135° with the blade chord length c.
[0013] According to the present invention, further, the external power source is a high-pressure air pump.
[0014] As a second aspect of the present invention, an application of a jet-driven vertical axis wind turbine is also provided, which is characterized in that when the wind speed is low, the jet is ejected from the first jet slit and sprayed toward the side and rear of the blade, providing the blade with the thrust required for starting; when the speed needs to be reduced, the jet is ejected from the second jet slit and sprayed toward the side and front of the blade, providing additional rotational resistance for the high-speed rotating blade.
[0015] Preferably, after the blades are started, the air pump is stopped to inflate.
[0016] Compared with the prior art, the beneficial effect of the present invention is that the present invention applies lateral jets in the slits on both sides of the vertical axis wind turbine blades. Under low wind speed conditions, the trailing edge jets on both sides are sprayed toward the side and rear of the blades, and the recoil force generated by the jets is used to provide the necessary starting torque for the wind turbine, prompting it to start rotating. Under high wind speed conditions, the trailing edge jets on both sides are sprayed toward the side and front of the blades, and the same recoil principle is used to hinder the rotation of the wind turbine, achieving a deceleration effect, which is equivalent to a pneumatic brake mechanism. This method can effectively control the operation of the wind turbine at different wind speeds and improve its efficiency and safety. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1a It is a schematic cross-sectional view of a blade of the present invention;
[0018] Figure 1b is an axonometric view of a blade of the present invention;
[0019] Figure 2a A schematic diagram of the jet direction when the blade of the present invention is started;
[0020] Figure 2b It is a schematic diagram of the jet direction of the blade deceleration of the present invention;
[0021] Figure 3 It is a schematic diagram showing the comparison results of the start-up time between a traditional lift-type vertical axis wind turbine and the vertical axis wind turbine of the present invention.
[0022] The reference numerals are as follows: 10 - blade, 1 - first jet slit, 2 - second jet slit, 3 - first high-pressure air cavity, 4 - second high-pressure air cavity, 20 - air pump, 30 - chassis. DETAILED DESCRIPTION
[0023] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer according to the following description. It should be noted that the accompanying drawings are all in a very simplified form and are not in precise proportions, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention.
[0024] As shown in Figures 1(a) and 1(b), this embodiment provides a side jet-driven vertical axis wind turbine, including a blade 10. The blade 10 is in the shape of an elongated plate, and its cross section is a typical NACA series airfoil. The leading edge of the cross section is arc-shaped, and the other end opposite to the end is sharp, i.e., the trailing edge end. The upper and lower surfaces of the blade 10 are provided with a first jet slit 1 and a second jet slit 2 arranged along the length direction thereof, and both ends of the first jet slit 1 and the second jet slit 2 overlap with the blade edge on the corresponding side; the first jet slit 1 and the second jet slit 2 located on the same side are 45° and 135° with the blade chord length c respectively; accordingly, the blade 10 is provided with a first high-pressure air cavity 3 and a second high-pressure air cavity 4 fitted therewith, and the upper and lower ends of the first high-pressure air cavity 3 are respectively connected to the first jet slit 1 on the corresponding side, and the upper and lower ends of the second high-pressure air cavity 4 are respectively connected to the second jet slit 2 on the corresponding side; the intersection surface of the first high-pressure air cavity 3 and the second high-pressure air cavity 4 is 15% c from the trailing edge, where c is the chord length. The first high-pressure air cavity 3 and the second high-pressure air cavity 4 are respectively connected to two small high-pressure air pumps 20 below them, as shown in FIG1(b), and the two air pumps 20 are placed on the chassis 30 at the lower end of the blade. When the wind speed is low, high-pressure gas is injected into the air cavity through the high-pressure air pump 20 connected to the first high-pressure air cavity 3. These gases are sprayed to the side and rear of the blade 10 through the first jet slit 1, providing the blade with the required thrust for starting and causing the blade to start rotating, as shown in Figure 2(a). Once the blade is successfully started, the inflation process of the air pump can be stopped to save energy. When the wind speed is high and brake protection is required, the high-pressure air pump 20 connected to the second high-pressure air cavity 4 is started to inject high-pressure gas into the air cavity. These gases are sprayed to the side and front of the blade through the second jet slit 2, providing additional rotational resistance to the high-speed rotating blade, thereby reducing its rotational torque and causing it to decelerate, as shown in Figure 2(b). By adjusting the flow rate of the air pump to increase the jet speed, the time required for blade starting or deceleration can be effectively shortened. Research results show that by using this technology, the self-starting time of the lift-type vertical axis wind turbine can be shortened by about 60% compared with traditional models. For specific effects, see Figure 3 .
[0025] The above technical solution solves the following problems, namely, in order to achieve high-speed rotation of the existing lift-type blades, the original resistance-type blades will become an additional source of resistance, thereby reducing the overall wind energy conversion efficiency of the wind turbine or using blade pitch technology, or by adjusting the angle of attack of the blades to reduce the resistance at startup, thereby improving the self-starting performance of the lift-type vertical axis wind turbine, which cannot be solved by achieving deceleration of the impeller at high wind speeds.
[0026] The working principle of the present invention is as follows: under low wind speed conditions, high-pressure gas is injected into the first high-pressure air cavity 3 with the help of a high-pressure air pump 20, and the jet is ejected toward the rear side of the blade 10 through the first jet slit 1, thereby pushing the blade 10 to start and rotate; while under high wind speed conditions, high-pressure gas is filled into the second high-pressure air cavity 4 with the help of a high-pressure air pump 20, and the jet is ejected toward the front side of the blade 10 through the second jet slit 2, thereby increasing the resistance to the rotation of the blade 10, gradually reducing its rotation speed, and ultimately achieving a braking effect.
[0027] The above description is only a description of the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention. Any changes or modifications made by a person skilled in the art in the field of the present invention based on the above disclosure shall fall within the scope of protection of the claims.
Claims
1. A side jet driven vertical axis wind turbine, comprising blades, characterized in that: A jet slit assembly with an opposite jetting direction is arranged near the trailing edge of the blade surface, and a high-pressure cavity connected to the jet slit assembly is arranged inside the blade, and the high-pressure cavity is connected to an external power source; When starting is required, the power supplied by the external power source is ejected from the forward jet slit assembly through the high-pressure cavity to provide starting power for the blades; when deceleration is required, the power supplied by the external power source is ejected from the reverse jet slit assembly through the high-pressure cavity to provide resistance for the blades.
2. A side jet driven vertical axis wind turbine as claimed in claim 1, characterized in that: The jet slit assembly comprises a first jet slit and a second jet slit arranged along the length direction of the blade, and the jet directions of the first jet slit and the second jet slit are opposite; when starting is required, the jet flows out from the first jet slit to provide power for the blade rotation; when deceleration is required, the jet flows out from the second jet slit to provide resistance for the blade rotation.
3. A side jet driven vertical axis wind turbine as claimed in claim 2, characterized in that: The blade is provided with a first high-pressure air cavity and a second high-pressure air cavity fitted therewith, the upper and lower ends of the first high-pressure air cavity are respectively connected to the first jet slit on the corresponding side, and the upper and lower ends of the second high-pressure air cavity are respectively connected to the second jet slit on the corresponding side.
4. A side jet driven vertical axis wind turbine as claimed in claim 3, characterized in that: The length between the intersection surface of the first high-pressure air cavity and the second high-pressure air cavity and the trailing edge is 15%c, where c is the chord length.
5. A side jet driven vertical axis wind turbine as claimed in claim 2, characterized in that: The first jet slit and the second jet slit are respectively 45° and 135° with the blade chord length c.
6. A side jet driven vertical axis wind turbine as claimed in claim 2 or 5, characterized in that: The upper and lower surface sides of the blade are both provided with a first jet slit and a second jet slit.
7. A side jet driven vertical axis wind turbine as claimed in claim 1, characterized in that: The external power source is a high-pressure air pump.
8. An application of a vertical axis wind turbine driven by a side jet according to any one of claims 1 to 7, characterized in that: When the wind speed is low, the jet is ejected from the first jet slit and sprayed toward the side and rear of the blade, providing the blade with the thrust required for starting; when the speed needs to be reduced, the jet is ejected from the second jet slit and sprayed toward the side and front of the blade, providing additional rotational resistance for the high-speed rotating blade.
9. The use of a side jet driven vertical axis wind turbine as claimed in claim 8, characterized in that: After the blades start, stop the air pump to inflate.