A multi-layer staggered φ-type wind turbine

Abstract

The present invention discloses a multi-layer staggered φ-type wind turbine blade structure, which includes a wind turbine shaft and several layers of curved blade groups with wing-shaped cross sections. The several layers of curved blade groups are fixed on the wind turbine shaft in an inner and outer layered manner. Each layer of curved blade group includes several curved blades, and the curved blades are all φ-type wind turbine blades with upper and lower ends fixed to the wind turbine shaft and the middle part bent outward. The inner layer of curved blades and the outer layer of curved blades are staggered at a certain angle and arranged circumferentially around the wind turbine shaft. The present invention can effectively improve the wind capture capability, thereby improving the self-starting performance. The positions where the wind turbine blade structures of each layer are fixed to the wind turbine shaft are also symmetrically distributed, which can enhance the integrity of the structure, improve the buckling stability of the wind turbine shaft, and improve the utilization rate of wind energy. The curved blades are fixed to the wind turbine shaft through bolt sleeves, so that the installation and removal of the inner layer of wind turbine blades are simple and easy to maintain.

Description

Technical Field

[0001] The present invention belongs to the field of vertical axis wind turbines, and in particular relates to a lift-type vertical axis wind turbine in which wind turbine curved blades with different rotation radii are arranged according to a certain rule, and specifically, to a multi-layer staggered φ-type wind turbine. Background Art

[0002] As the energy supply problem becomes increasingly serious, wind energy as an ideal renewable clean energy has attracted widespread attention. The wind turbines currently used mainly include horizontal axis wind turbines and vertical axis wind turbines. Compared with horizontal axis wind turbines, vertical axis wind turbines have the advantages of good safety, low noise, easy installation and low maintenance cost. They have broad application prospects in urban energy conservation and environmental protection construction.

[0003] The traditional φ-type lift wind turbine has a good wind energy capture capability at a suitable wind speed, but it is difficult to start at a lower wind speed, and it is also difficult to start under certain wind directions. This will affect the promotion and use of curved blade vertical axis wind turbines. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a multi-layer staggered φ-type wind turbine with improved self-starting performance and adaptability to more wind directions in view of the deficiencies of the above-mentioned prior art.

[0005] In order to achieve the above technical objectives, the technical solution adopted by the present invention is:

[0006] A multi-layer staggered φ-shaped wind turbine blade structure, which includes: a wind turbine shaft and several layers of curved blade groups with wing-shaped cross-sections, the several layers of curved blade groups are fixed on the wind turbine shaft in an inner and outer layered manner, each layer of curved blade group includes several curved blades, and the curved blades are all φ-shaped wind turbine blades with the upper and lower ends fixed to the wind turbine shaft and the middle part bent outward, and the inner layer of curved blades and the outer layer of curved blades are staggered at a certain angle and arranged circumferentially around the wind turbine shaft.

[0007] To optimize the above technical solutions, the specific measures taken also include:

[0008] The curved blades of each curved blade group mentioned above are staggered at the same angle with the curved blades of the curved blade group next to it, and the angle is α. The maximum number of layers n of the curved blade group is: n=[120 / α], where n is a natural number.

[0009] The cross-sectional dimensions of the inner curved blades and the outer curved blades are the same.

[0010] The ratio of the rotation radius of the outer curved blade to the rotation radius of the curved blade immediately inside the outer curved blade is 3:2.

[0011] The central axes of the curved blades of each layer of the curved blade groups in the horizontal direction are all located in the same horizontal plane.

[0012] The staggered angle of the curved blades of the adjacent curved blade groups is 15° or 20°.

[0013] Bolt sleeves are fixedly installed at both ends of the above-mentioned curved blades. Bolt holes for bolts to pass through are opened on the bolt sleeves. The bolts pass through the bolt sleeves and the fixing holes reserved on the wind turbine shaft at the same time to fix the curved blades on the wind turbine shaft.

[0014] Each layer of the curved blade group mentioned above includes three curved blades, and the three curved blades are arranged with equal arcs around the wind turbine shaft; accordingly, the upper and lower ends of the curved blades are welded to the arc-shaped bolt sleeves, and the three arc-shaped bolt sleeves are closely clamped around the wind turbine shaft.

[0015] The lower end of the wind turbine shaft is fixed on the wind turbine tower and can rotate relative to the wind turbine tower.

[0016] A multi-layer staggered φ-type wind turbine blade structure of the present invention is provided with a multi-layer aerofoil curved blade group, and each layer of aerofoil curved blades are staggered at the same angle with the aerofoil curved blades of a layer adjacent to the outside thereof, and the staggered angle can be selected as 15° or 20°. When the staggered angle remains unchanged, the maximum number of layers that can be stacked is determined by comparing the change in the moment coefficient. This wind turbine blade structure with multiple stacked layers can effectively improve the wind capture capability, thereby improving the self-starting performance. The positions of each layer of wind turbine blade structure fixed to the wind turbine shaft are also symmetrically distributed, which can enhance the integrity of the structure, improve the buckling stability of the wind turbine shaft, and improve the utilization rate of wind energy. The curved blades are fixed to the wind turbine shaft by bolt sleeves, so that the installation and removal of the inner layer of wind turbine blades are simple and easy to maintain. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The overall structure diagram of the double-layer staggered φ-type wind turbine of the present invention, the staggered angle is 20°;

[0018] Figure 2 It is a top view of the double-layer staggered φ-type wind turbine of the present invention, and the staggered angle is 20°;

[0019] Figure 3 The overall structure diagram of the three-layer staggered φ-type wind turbine of the present invention is shown, and the staggered angle is 20°;

[0020] Figure 4 It is a top view of a three-layer staggered φ-type wind turbine of the present invention, with a staggered angle of 20°;

[0021] Figure 5 Schematic diagram of the local structure fixed with bolts.

[0022] The reference numerals are: wind turbine shaft 1 , curved blade 2 , bolt sleeve 3 , bolt 4 , wind turbine tower 5 . DETAILED DESCRIPTION

[0023] The embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings.

[0024] A multi-layer staggered φ-type wind turbine blade structure of the present embodiment comprises a wind turbine shaft 1 and several layers of curved blade groups with wing-shaped cross sections, wherein the several layers of curved blade groups are fixed on the wind turbine shaft 1 in an inner and outer layered manner, and each layer of curved blade groups comprises several curved blades 2, and the curved blades 2 are all φ-type wind turbine blades with the upper and lower ends fixed to the wind turbine shaft 1 and the middle part bent outward, and the inner layer of curved blades and the outer layer of curved blades are staggered at a certain angle and arranged circumferentially around the wind turbine shaft.

[0025] In the embodiment, the curved blades 2 of each curved blade group are staggered with the curved blades 2 of the curved blade group next to it at the same angle, denoted as α, and the maximum number of layers n of the curved blade group is: n=[120 / α], where n is a natural number.

[0026] In the embodiment, the cross-sectional dimensions of the inner curved blades 2 and the outer curved blades 2 are the same.

[0027] In the embodiment, the ratio of the rotation radius of the outer curved blade 2 to the rotation radius of the curved blade 2 immediately inside the outer curved blade 2 is 3:2.

[0028] In the embodiment, the central axes of the curved blades 2 of each layer of the curved blade group in the horizontal direction are all located in the same horizontal plane.

[0029] In the embodiment, the staggered angle of the curved blades 2 of adjacent curved blade groups is 15° or 20°.

[0030] In the embodiment, bolt sleeves 3 are fixedly installed at both ends of the curved blade 2. Bolt holes for bolts 4 to pass through are opened on the bolt sleeves 3. The bolts 4 pass through the bolt sleeves 3 and the fixing holes reserved on the wind turbine shaft 1 at the same time to fix the curved blade 2 on the wind turbine shaft 1.

[0031] In the embodiment, each layer of curved blade group includes three curved blades 2, and the three curved blades 2 are arranged with equal arcs around the wind turbine shaft 1; accordingly, the upper end and the lower end of the curved blade 2 are welded to the arc-shaped sheet-shaped bolt sleeve 3, and the three arc-shaped sheet-shaped bolt sleeves 3 are closely surrounded around the wind turbine shaft 1.

[0032] The lower end of the wind turbine shaft 1 is fixed on the wind turbine tower 5 and can rotate relative to the wind turbine tower 5 .

[0033] like Figure 1The figure shows a double-layer staggered φ-type wind turbine blade structure, including a wind turbine shaft 1, curved blades 2, bolt sleeves 3, bolts 4 and a tower 5. Three airfoil curved blades are evenly installed on the inner and outer layers around the wind turbine shaft, and the angle between adjacent curved blades of the same size in each layer is 120°, and the angle between curved blades of different rotation radii in adjacent layers is 20°; the small blades of the inner layer are fixed to the wind turbine shaft along the center of the vertical height of the curved blades adjacent to the outer side, and the upper and lower parts of the three airfoil curved blades of each inner layer except the outer layer are welded to the arc-shaped bolt sleeves, and the three arc-shaped sleeves are closely clamped around the wind turbine shaft. The local structure of bolt fixing is shown in FIG. Figure 3 shown.

[0034] The torque coefficient of a certain φ-type wind turbine with three blades changes with the rotation position angle when the tip speed ratio is constant, and its total torque coefficient rarely produces negative torque. When the staggered angle is 20°, and the angle between the innermost curved blade and the outermost curved blade is 100° or 20°, the number of layers of the wind turbine should not be increased further. On the one hand, the additional layer of blades will overlap with the outermost blades; on the other hand, the reduction of the rotation radius will definitely reduce the torque coefficient of the corresponding layer. The increase in the number of layers will increase the cost, and the corresponding increase in the torque coefficient is not large, which is not economical.

[0035] Therefore, when the staggered angle α is determined, the maximum number of stacked layers n is: n=[120 / α] ([ ] is rounded down).

[0036] The above are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should be regarded as the protection scope of the present invention.

Claims

1. A multi-layer staggered φ-shaped wind turbine blade structure, characterized by: The invention comprises a wind turbine shaft (1) and a plurality of layers of curved blade groups with wing-shaped cross sections, wherein the plurality of layers of curved blade groups are fixed on the wind turbine shaft (1) in an inner and outer layered manner, wherein each layer of curved blade groups comprises a plurality of curved blades (2), wherein the curved blades (2) are all φ-shaped wind turbine blades with their upper and lower ends fixed to the wind turbine shaft (1) and their middle portions bent outwardly, and the inner layer of curved blades and the outer layer of curved blades are staggered at a certain angle and arranged circumferentially around the wind turbine shaft; The curved blades (2) of each curved blade group are staggered at the same angle as the curved blades (2) of the curved blade group immediately outside the curved blade group, and the angle is α. The maximum number of layers n of the curved blade groups is: n=[120 / α], where n is a natural number; The cross-sectional dimensions of the inner curved blades (2) and the outer curved blades (2) are the same; The ratio of the rotation radius of the outer curved blade (2) to the rotation radius of the curved blade (2) immediately inside the outer curved blade (2) is 3:2; The central axes of the curved blades (2) of each layer of the curved blade group in the horizontal direction are all located in the same horizontal plane; The staggered angles of the curved blades (2) of adjacent curved blade groups are 15° or 20°.

2. A multi-layer staggered φ-shaped wind turbine blade structure according to claim 1, characterized in that: Bolt sleeves (3) are fixedly mounted at both ends of the blade (2), and the bolt sleeves (3) are provided with bolt holes for the bolts (4) to pass through. The bolts (4) pass through the bolt sleeves (3) and the fixing holes reserved on the wind turbine shaft (1) at the same time, thereby fixing the curved blade (2) on the wind turbine shaft (1).

3. The multi-layer staggered φ-shaped wind turbine blade structure according to claim 2 is characterized in that: Each layer of curved blade group comprises three curved blades (2), and the three curved blades (2) are arranged with equal arcs around the wind turbine shaft (1); accordingly, the upper end and the lower end of the curved blade (2) are welded to the arc-shaped sheet-shaped bolt sleeve (3), and the three arc-shaped sheet-shaped bolt sleeves (3) are closely encircled around the wind turbine shaft (1).

4. The multi-layer staggered φ-shaped wind turbine blade structure according to claim 3 is characterized by: The lower end of the wind turbine shaft (1) is fixed on the wind turbine tower (5) and can rotate relative to the wind turbine tower (5).

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