Twisted wind turbine blade
By designing a twisted blade, combined with a wind-catching section and drag-reducing protrusions, the problems of poor self-starting capability and stalling under high wind speed of vertical axis wind turbines are solved, achieving the effect of starting in light wind and high speed. The structure is simple and easy to manufacture.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- WEIFANG ZHOULEI BUILDING MATERIALS CO LTD
- Filing Date
- 2025-07-31
- Publication Date
- 2026-06-19
AI Technical Summary
Traditional vertical shaft wind turbines have poor self-starting capability of their blades, making it difficult to generate enough torque to drive the rotating shaft at low wind speeds. They are also prone to stalling when wind speed changes, resulting in low power generation efficiency. Existing improvement solutions are complex and costly.
It adopts a twisted blade design, with the outer blade and bottom blade arranged in a spiral shape. The windward side is equipped with a wind-catching part, which guides the wind force in combination with the twisted path to increase the wind force receiving capacity. A drag-reducing protrusion is set on the back to reduce drag, forming an L-shaped cross-section structure.
It achieves strong start-up capability under light wind conditions, high rotational speed at high wind speeds, simple structure, and easy manufacturing, reducing stall problems caused by wind speed changes and improving power generation efficiency.
Smart Images
Figure CN224379995U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of wind turbine technology, and in particular to a twisted blade for a wind turbine. Background Technology
[0002] A vertical axis wind turbine (VAWT) is a wind power generation device with its rotor shaft perpendicular to the ground. Compared to the traditional horizontal axis wind turbine (HAWT), it has advantages such as simple structure, good wind direction adaptability, low noise, and convenient maintenance, making it particularly suitable for urban environments or low-wind-speed areas. This type of wind turbine typically has two, three, or more blades mounted on its rotating shaft to receive wind power. The wind forces the rotating shaft to rotate, which in turn causes the generator's main rotor to cut through the magnetic field, generating electricity.
[0003] Traditional vertical-axis wind turbines use straight blades and rely primarily on lift for drive. They have poor self-starting capability and struggle to generate sufficient torque to rotate the shaft at low wind speeds, typically requiring wind speeds of 3–4 m / s to start. Furthermore, they are highly sensitive to variations in wind speed and load, and stalling can occur with rapid changes in wind speed or increased load, resulting in overall low power generation efficiency and limiting their application. While some technologies, such as composite impellers or self-adjusting blade angles, have been developed to mitigate these shortcomings, these have introduced increased manufacturing complexity and cost, and have not significantly improved the inability to achieve high rotational speeds at high wind speeds. Utility Model Content
[0004] The technical problem to be solved by this utility model is to provide a twisted blade for a wind turbine that is simple in structure, easy to manufacture, has strong wind receiving ability, facilitates start-up in light winds, and facilitates high speed at high wind speeds.
[0005] To solve the above-mentioned technical problems, the technical solution of this utility model is: a twisted blade for wind turbine, used to be configured on the rotating shaft of a wind turbine, including an outer blade facing the rotating shaft, the outer blade being arranged in a spiral shape around the rotating shaft; a bottom blade extending towards the rotating shaft is fixedly provided at one of the spiral edges of the outer blade, the near surfaces of the outer blade and the bottom blade are respectively the windward surfaces, and a wind-catching part is provided at the windward surfaces of the outer blade and / or the windward surfaces of the bottom blade.
[0006] As a preferred technical solution, the wind-catching part is a groove recessed on the corresponding windward side.
[0007] As a preferred technical solution, the wind-catching part includes a wind-catching groove side that is arranged intersecting the wind-guiding direction of the blade.
[0008] As a preferred technical solution, the wind-catching part further includes a reinforcing groove along the air-guiding direction of the blade.
[0009] As a preferred technical solution, the wind-catching section is a strip-shaped part arranged along the air-guiding direction of the blade.
[0010] As a preferred technical solution, the wind-catching section is a strip shape that is intersected with the air-guiding direction of the blades.
[0011] As a preferred technical solution, the wind-catching part is a protrusion that is arranged intersecting the air-guiding direction of the blade.
[0012] As a preferred technical solution, the far surfaces of the outer blade and the bottom blade are respectively the leeward side, and the leeward side of the outer blade and / or the leeward side of the bottom blade are provided with drag-reducing protrusions.
[0013] As a preferred technical solution, a rotating shaft connection is fixedly provided on the windward side of the outer blade and / or the windward side of the bottom blade.
[0014] Due to the adoption of the above technical solution, the twisted blade of the wind turbine is configured on the rotating shaft of the wind turbine. It includes an outer blade facing the rotating shaft, the outer blade being spirally arranged around the rotating shaft. A bottom blade extending towards the rotating shaft is fixed at one spiral edge of the outer blade. The near-surface surfaces of the outer blade and the bottom blade are respectively the windward surfaces. A wind-catching section is provided on the windward surface of the outer blade and / or the windward surface of the bottom blade. This invention utilizes the outer blade and the bottom blade to jointly form a roughly L-shaped cross-section of the blade, improving its ability to receive incoming wind. The addition of the wind-catching section, combined with the wind-guiding effect of the twisted path, promotes more efficient utilization of the incoming wind force, achieving greater torque in light wind conditions and facilitating light wind start-up. Furthermore, the back surfaces of the outer blade and the bottom blade form an approximately spindle-shaped structure, resulting in low wind resistance. Therefore, when multiple blades are installed on the rotating shaft, the blade stall problem is not significant when wind speed changes, which is beneficial for achieving high speeds at high wind speeds. This utility model has a thin plate-like structure, which is simple in structure, flexible in processing method, and convenient to manufacture. Attached Figure Description
[0015] The following figures are intended only to illustrate and explain the present invention and do not limit the scope of the present invention. Wherein:
[0016] Figure 1 This is a three-dimensional structural schematic diagram of Embodiment 1 of this utility model;
[0017] Figure 2 yes Figure 1 A schematic diagram of the AA magnified structure;
[0018] Figure 3 yes Figure 1 A schematic diagram of the enlarged BB structure;
[0019] Figure 4 This is a schematic diagram of the structure of Embodiment 1 of this utility model configured on the rotating shaft;
[0020] Figure 5 This is a three-dimensional structural schematic diagram of Embodiment 2 of this utility model;
[0021] Figure 6 This is a three-dimensional structural schematic diagram of Embodiment 3 of this utility model;
[0022] Figure 7 This is a three-dimensional structural schematic diagram of Embodiment 4 of this utility model;
[0023] Figure 8 This is a three-dimensional structural schematic diagram of Embodiment 5 of this utility model;
[0024] Figure 9 This is a three-dimensional structural diagram of Embodiment Six of this utility model;
[0025] Figure 10 This is a three-dimensional structural schematic diagram of Embodiment Seven of this utility model;
[0026] Figure 11 This is a three-dimensional structural schematic diagram of Embodiment 8 of this utility model;
[0027] Figure 12 yes Figure 11 Enlarged schematic diagram of the structure at point I.
[0028] In the figure: 1-rotating shaft; 2-outer blade; 3-bottom blade; 4-wind catcher; 41-wind catcher groove edge; 42-reinforcing groove edge; 5-drag reduction protrusion; 6-shaft connection part. Detailed Implementation
[0029] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the following detailed description, only certain exemplary embodiments of the present invention are described by way of illustration. Undoubtedly, those skilled in the art will recognize that various modifications can be made to the described embodiments without departing from the spirit and scope of the present invention. Therefore, the drawings and description are illustrative in nature and not intended to limit the scope of the claims.
[0030] Example 1: As Figure 1 and Figure 4As shown, a twisted blade for a wind turbine is mounted on the rotating shaft 1 of the wind turbine, including an outer blade 2 facing the rotating shaft 1. Conventionally, the blade is a thin, sheet-like structure with two surfaces, one of which faces the rotating shaft 1, thus constituting the aforementioned orientation facing the rotating shaft 1. Of course, this orientation is not strictly a normal direction; as long as the surface generally faces the rotating shaft 1, it is within the protection range of this orientation.
[0031] The outer blade 2 is arranged in a spiral shape around the rotation axis 1. A bottom blade 3 extending towards the rotation axis 1 is fixedly provided at one of the spiral edges of the outer blade 2. Thus, the outer blade 2 and the bottom blade 3 form a roughly L-shaped cross-section of the fan blade, and the fan blade as a whole is twisted. The near surfaces of the outer blade 2 and the bottom blade 3 are the windward surfaces. Therefore, when the windward surfaces of the outer blade 2 and the bottom blade 3 face the wind together, they can exhibit a better ability to gather airflow, that is, they can gather a larger volume of airflow to generate rotational driving force. After facing the wind, the airflow flows upward or downward along the twisted shape of the fan blade, and the fan blade itself generates an airflow guiding effect. Under this effect, the resistance problem caused by the direct wind on the outer blade 2 can be reduced, and the airflow can drive the fan blade to form a more stable rotation. The outer blade 2 and the bottom blade 3 form an approximately spindle-shaped structure on their back sides, resulting in low wind resistance. When the back side is partially in a windward state, there is no significant resistance problem. Therefore, the blade stall problem is not obvious when the wind speed changes, which is conducive to achieving high speed at high wind speeds.
[0032] When the bottom blade 3 is located at the lower edge of the outer blade 2, the airflow is guided upward in this embodiment; when the bottom blade 3 is located at the upper edge of the outer blade 2, the airflow is guided downward in this embodiment. This embodiment only illustrates the former.
[0033] like Figures 1 to 4 As shown, the windward side of the outer blade 2 and / or the windward side of the bottom blade 3 are provided with a wind-catching part 4, which can further improve the wind-catching capacity. The wind-catching part 4 can also cooperate with the wind-guiding effect of the blade twisting path to make the airflow generate a secondary driving effect, thereby enabling the generator to achieve greater torque in light wind conditions, which is conducive to realizing the generator's light wind start-up.
[0034] In this embodiment, both the windward side of the outer blade 2 and the windward side of the bottom blade 3 are provided with the wind-catching part 4. Furthermore, in this embodiment, the wind-catching part 4 is a groove-shaped recess in the corresponding windward side. This groove structure achieves the aforementioned effect of improving wind-catching capacity. (Refer to...) Figure 2The airflow gathered in the groove structure is guided along a twisted path and then impacts the groove edge of the groove structure a second time. The horizontal component of the impact force at the groove edge achieves the aforementioned secondary pushing effect. Accordingly, the wind-collecting part 4 includes at least a wind-collecting groove edge 41 that intersects with the airflow direction of the blades to achieve the aforementioned secondary pushing effect. In this embodiment, when the blades guide the airflow upwards, the wind-collecting groove edge 41 is the upper groove edge of the wind-collecting part 4; conversely, when the blades guide the airflow downwards, the wind-collecting groove edge 41 is the lower groove edge of the wind-collecting part 4.
[0035] The choke section 4 also includes reinforcing grooves 42 along the airflow direction of the blade, which simultaneously strengthen the thin-plate-shaped blade, reduce structural deformation during operation, and promote long-term stable operation. In this embodiment, the choke section 4 is schematically a rectangular groove, and its two grooves along the airflow direction of the blade are the reinforcing grooves 42.
[0036] The far surfaces of the outer blade 2 and the bottom blade 3 are respectively the leeward surfaces, and drag-reducing protrusions 5 are provided on the leeward surfaces of the outer blade 2 and / or the bottom blade 3. Figure 3 As shown, the drag-reducing protrusion 5 can produce a better drag reduction effect on the back side of the bottom blade 3, especially the outer blade 2, when facing the wind directly, further ensuring the breeze start-up effect of this embodiment.
[0037] Since both the outer blade 2 and the bottom blade 3 described in this embodiment are thin plate structures, the recess of the wind-catching part 4 can directly form the drag-reducing protrusion 5 on the leeward side. This can be achieved in one piece through die pressing, which simplifies the manufacturing process. Of course, the drag-reducing protrusion 5 and the wind-catching part 4 are not in a one-to-one correspondence. When die pressing is not used, the quantity, size and shape can be set separately.
[0038] A rotating shaft connecting part 6 is fixedly provided on the windward side of the outer blade 2 and / or the windward side of the bottom blade 3 to achieve configuration on the rotating shaft 1. The rotating shaft connecting part 6 can be set according to the actual connection method, and is not limited here.
[0039] This embodiment utilizes the outer blades 2 and the bottom blades 3 to form a roughly L-shaped cross-section of the wind turbine, improving its ability to receive incoming wind. The addition of the catching section 4 further enhances the catching capacity and, combined with the wind-guiding effect of the twisted path, promotes more efficient utilization of the incoming wind force, achieving greater torque even in light winds and facilitating start-up in light winds. Furthermore, the back surfaces of the outer blades 2 and the bottom blades 3 form an approximately spindle-shaped structure, resulting in low wind resistance. Therefore, when multiple blades are mounted on the rotating shaft 1, the problem of wind turbine stalling during wind speed changes is not significant, facilitating high rotational speeds at high wind speeds. This embodiment presents a thin-plate structure overall, with a simple design. It can be manufactured using various processing methods such as welding, die pressing, bending, casting, or mold casting, offering flexibility and ease of manufacturing.
[0040] Example 2: Figure 5 As shown, the difference between this embodiment and embodiment one is that: in this embodiment, the wind-catching part 4 is provided only on the windward side of the bottom blade 3, so there is wind-catching enhancement and secondary propulsion at least at the bottom blade 3, which is also conducive to achieving start-up in a light breeze and achieving high rotation speed at high wind speed, and the structure is simpler and easier to manufacture.
[0041] Example 3: Figure 6 As shown, the difference between this embodiment and embodiment one is that: in this embodiment, the wind-catching part 4 is provided only on the windward side of the outer blade 2, so there is wind-catching enhancement and secondary propulsion at least on the outer blade 2, which is also conducive to achieving start-up in a light breeze and achieving high rotation speed at high wind speed, and the structure is simpler and easier to manufacture.
[0042] Example 4: Figure 7 As shown, the difference between this embodiment and Embodiment 2 is that the wind-catching part 4 is schematically a triangular groove, with the upper groove side forming the wind-catching groove side 41, and the other two groove sides forming the reinforcing groove side 42. Accordingly, the reinforcing groove side 42 does not necessarily have to be strictly aligned with the airflow guiding direction; as long as the direction is roughly aligned, it can play a role in reinforcing the blades.
[0043] Example 5: Figure 8 As shown, the difference between this embodiment and embodiment two is that the wind-catching part 4 is schematically an elongated groove, and the arc-shaped groove edge on its upper side constitutes the wind-catching groove edge 41. Accordingly, the wind-catching groove edge 41 is not necessarily a straight groove edge. As long as its direction intersects with the airflow guiding direction, it can play the required secondary pushing role.
[0044] Example 6: Figure 9As shown, the difference between this embodiment and Embodiment 2 is that the wind-catching part 4 is a strip-shaped structure arranged along the air-guiding direction of the blades, that is, it is a strip-shaped groove structure. Under this structure, the two ends of the strip-shaped groove can play a certain secondary pushing role, and the long groove side can achieve the required blade reinforcement effect. In actual installation, multiple parallel strip-shaped grooves can be set to improve the secondary pushing effect.
[0045] Example 7: Figure 10 As shown, the difference between this embodiment and Embodiment 2 is that the wind-catching section 4 is a strip-shaped section intersecting the air-guiding direction of the blades. The long groove side on the upper side of this strip-shaped groove constitutes the wind-catching groove side 41, which can still achieve a certain secondary pushing effect. In actual use, the wind-catching section 4 of this structure can be used in combination with wind-catching sections 4 of other structures.
[0046] Example 8: Figure 11 and Figure 12 As shown, the difference between this embodiment and embodiment two is that the wind-catching part 4 is a protrusion arranged intersecting the wind-guiding direction of the blade. Under this structure, the two adjacent wind-catching parts 4 are also approximately grooved, which can also have the function of enhancing wind-catching ability and the required secondary propulsion.
[0047] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope. For example, both the outer blade 2 and the bottom blade 3 may be provided with, or only the outer blade 2 may be provided with, a duct 4 of triangular, oblong, strip-shaped, or protruding shapes, as well as a mixture of ducts 4 of different shapes on each blade, etc. All such changes and modifications fall within the scope of this utility model as claimed. The scope of protection of this utility model is defined by the appended claims and their equivalents.
Claims
1. A twisted blade for a wind turbine, used for mounting on the rotating shaft of a wind turbine, characterized in that: It includes an outer blade facing the rotation axis, the outer blade being spirally arranged around the rotation axis; a bottom blade extending towards the rotation axis is fixedly provided at one of the spiral edges of the outer blade, the near surfaces of the outer blade and the bottom blade are respectively the windward surfaces, and a wind-catching part is provided at the windward surfaces of the outer blade and / or the windward surfaces of the bottom blade.
2. The twisted blade of the wind turbine as described in claim 1, characterized in that: The wind-catching part is a groove-shaped recess on the corresponding windward side.
3. The twisted blade of the wind turbine as described in claim 2, characterized in that: The choke section includes a choke groove that is arranged intersecting the airflow direction of the blades.
4. The twisted blade of the wind turbine as described in claim 3, characterized in that: The choke section also includes a reinforcing groove along the air guiding direction of the blades.
5. The twisted blade of a wind turbine as described in claim 2, characterized in that: The choke section is a strip-shaped section arranged along the air guiding direction of the blades.
6. The twisted blade of a wind turbine as described in claim 2, characterized in that: The choke section is a strip-shaped section that is arranged intersecting the airflow direction of the blades.
7. The twisted blade of a wind turbine as described in claim 1, characterized in that: The choke section is a protrusion that is arranged intersecting the airflow direction of the blades.
8. The twisted blade of a wind turbine as described in claim 1, characterized in that: The far surfaces of the outer blade and the bottom blade are respectively the leeward side, and the leeward side of the outer blade and / or the leeward side of the bottom blade are provided with drag-reducing protrusions.
9. The twisted blade of a wind turbine as described in any one of claims 1 to 8, characterized in that: A rotating shaft connection is fixedly provided on the windward side of the outer blade and / or the windward side of the bottom blade.