This application claims priority of Taiwanese Patent Application No. 110105413, filed on Feb. 17, 2021.
The disclosure relates to a wind turbine, and more particularly to a wind turbine with a flow deflection unit for influencing airflow flowing to press a tip of a rotor blade.
Referring to
Therefore, an object of the disclosure is to provide a wind turbine that can alleviate at least one of the drawbacks of the prior art.
According to the disclosure, the wind turbine includes an axle unit, at least one blade unit and at least one flow deflection unit. The axle unit has a tubular hub which is rotatable about a hub axis, and an inner tube which extends coaxially in the hub. The blade unit is rotatable by a wind power in an operational direction, and includes a plurality of blades which are connected with and extend radially and outwardly from the hub and which are angularly spaced apart from each other. Each of the blades has a wind hole formed at a root end thereof adjacent to the hub axis. The flow deflection unit includes a deflection plate which is disposed corresponding with the wind holes of the blades. The deflection plate is connected with the inner tube and extends and is curved along the operational direction. The deflection plate has a deflection surface which faces the inner tube to collect and deflect wind flow toward a corresponding one of the blades.
The blades have the wind holes formed at the root ends, and the deflection plate is disposed to deflect airflow through the wind holes toward the tip ends of the blades to generate a larger torque of the blades so as to enhance the rotating efficiency.
Other features and advantages of the disclosure will become apparent in the following detailed description of the embodiments with reference to the accompanying drawings, of which:
Before the disclosure is described in greater detail, it should be noted that where considered appropriate, reference numerals or terminal portions of reference numerals have been repeated among the figures to indicate corresponding or analogous elements, which may optionally have similar characteristics.
Referring to
For orientation explanation, the wind turbine defines a first reference plane 61 which is parallel to a windward direction, a second reference plane 62 which is perpendicular to the first reference plane 61, and first, second, third and fourth spaces 63, 64, 65, 66 which are divided by the first reference plane 61 and the second reference plane 62 and distributed in an opposite operational direction of the blade units 3. In terms of the first reference plane 61 as a boundary, the first and second spaces 63, 64 serve as a tailwind side, and the third and fourth spaces 65, 66 serve as a headwind side. In terms of the second reference plane 62 as a boundary, the second and third spaces 64, 65 serve as a windward side, and the first and fourth spaces 63, 66 serve as a leeward side.
The axle unit 2 has a tubular hub 22 which is rotatable about a hub axis 20, and an inner tube 21 which extends coaxially in the hub 22. The hub axis 20 overlaps an intersecting line of the first reference plane 61 and the second reference plane 62. In this embodiment, the hub axis 20 is a horizontal axis, and may be a vertical axis in other various embodiments. The inner tube 21 extends through the hub 22 and has a projecting portion 211 which is disposed outwardly of the hub 22.
The blade unit 3 is disposed at an end of the hub and surrounds the projecting portion 211 of the inner tube 21. The blade unit 3 includes three blades 31 which are connected with and extend radially and outwardly from the hub 22 and which are angularly spaced apart from one another. Each of the blades 31 has a wind hole 32 formed at a root end thereof adjacent to the hub axis 20. Each blade 31 is in form of a straight linear blade, a curved blade, or a partially straight linear and partially curved blade. In this embodiment, each blade 31 has a straight plate portion proximate to the wind hole 32, and a curved plate portion curved from the straight plate portion along the opposite operational direction. The length of the wind hole 32 is about 30% to 50% of the total length of the blade 31, 40% preferably. Each of the blades 31 has a windward surface 312 and a leeward surface 311 in terms of the operational direction 30. It is noted that the number of the blades 31 is the same as the number of the wind holes 32, but is not limited to three. Two, four or more blades 31 may be disposed. The blade unit 3 further includes two bearings 33 which are connected between the blades 31 and the projecting portion 211 of the inner tube 21. The bearings 33 are spaced apart from each other along the hub axis 20. One bearing 33 is securely disposed at the end of the hub 22, and the other one bearing 33 is remote from the hub 22.
The flow deflection unit 4 is fixed to the inner tube 21 and includes a deflection plate 41 which is disposed corresponding with the wind holes 32 of the blades 31 so as to permit passing of the deflection plate 41 through the wind holes 32 during rotation of the blades 31. Specifically, the blade unit 3 surrounds the deflection plate 41 and the projecting portion 211 of the inner tube 21. The deflection plate 41 is connected with the inner tube 21 and extends and is curved along the operational direction 30. The curvature of the deflection plate 41 may be n/6, n/4, n/3 or n/2, and is n/2 in this embodiment. The deflection plate 41 is disposed in the first space 63 to deflect wind flowing from the second space 64 toward the fourth space 66. The deflection plate 41 has a deflection surface 411 which faces the inner tube 21 to collect and deflect wind flow toward a corresponding one of the blades 31. The deflection unit 4 further includes a plurality of connecting elements 42 which interconnect the deflection plate 41 and the projecting portion 211 of the inner tube 21.
The electric generating unit 5 includes a driving gear 51 which is coupled with and driven by the hub 22, a transmitting gear 52 which meshes with the driving gear 51, a driven gear 53 which meshes with the transmitting gear 52, and a generator 54 which is coupled with the driven gear 53 so as to convert rotational energy from the hub 21 into electrical energy. The transmission of the electric generating unit 5 may be a chain or a belt, instead of the transmitting gear 52.
When wind blows to the second space 64 and the third space 65, the airflow near the peripheral area of the wind turbine flows to the windward surfaces 312 of the blades 31 and drives the blades 31 to rotate in the operational direction 30. The airflow near the central area of the wind turbine flows through the wind holes 32 and meets the deflection plate 41 such that the deflection surface 411 collects and deflects the airflow toward the fourth space 66 and toward the tip end of the blade 31. As such, a wind resistance applying to the leeward surfaces 311 of the blades 31 in the third space 65 can be reduced, and the torque to drive rotation of the blades 31 in the operational direction 30 can be increased so as to enhance the rotational efficiency. The blades 31 synchronously rotate the hub 22 to transmit the torque to the electric generating unit 5 for generating electricity.
With reference to
Moreover, the flow deflection unit 4 further includes two frame rails 43 which are mounted adjacent to two sides of the deflection plate 41 and connected with the projecting portion 211 of the inner tube 21 by the connecting elements 42, a plurality of rollers 44 which are mounted on the two sides of the deflection plate 41 and slidable within and along the frame rails 43, a mounting frame 45 which is connected with the projecting portion 211 of the inner tube 21 and disposed adjacent to ends of the frame rails 43, and two biasing elements 46 each of which is connected between the mounting frame 45 and the deflection plate 41 to permit the deflection plate 41 to be movable along the frame rails 43. When subjected to a wind with a high wind speed or wind level, such as a typhoon, the deflector 41 is slidable back and forth along the frame rails 43 in a buffered manner so as to prevent the deflection plate 41 from being bent or deformed due to an excessive wind pressure. The number of the biasing elements 46 is not limited to two, and may be one, three or more in other various embodiments.
The flow deflection unit 4 further includes two auxiliary deflection modules 47 which are spaced apart from each other along the operational direction 30 and which are respectively disposed at an entrance and an exit of the deflection plate 41. Each of the auxiliary deflection modules 47 has a support element 471 which is connected with the projecting portion 211 of the inner tube 21, an auxiliary plate 472 which is pivotally connected with the support element 471 and which extends toward the deflection plate 41, and a biasing body 473, such as a biasing spring, a rubber block, a balloon, etc., which is connected between the support element 471 and the auxiliary plate 472 such that the auxiliary plate 472 movably conducts and diverts airflow through the deflection plate 41. Specifically, the auxiliary plate 472 at the entrance of the deflection plate 41 conducts and deflects a part of airflow to the deflection plate 41, and the auxiliary plate 472 at the exit of the deflection plate 41 diverts a large part of the airflow toward the tip end of the blades 31 and a small part of the airflow through the wind holes 32 so as to increase the driving force and reduce a negative pressure.
With reference to
With reference to
As illustrated, the blades 31 have the wind holes 32 formed at the root ends, and the deflection plate 41 is disposed to deflect airflow through the wind holes 32 toward the tip ends of the blades 31 to generate a larger torque of the blades 31 so as to enhance the rotating efficiency. Moreover, with the wind holes 32, the manufacturing costs and weights of the blades 31 can be reduced.
In the description above, for the purposes of explanation, numerous specific details have been set forth in order to provide a thorough understanding of the embodiments. It will be apparent, however, to one skilled in the art, that one or more other embodiments may be practiced without some of these specific details. It should also be appreciated that reference throughout this specification to “one embodiment,” “an embodiment,” an embodiment with an indication of an ordinal number and so forth means that a particular feature, structure, or characteristic may be included in the practice of the disclosure. It should be further appreciated that in the description, various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of various inventive aspects.
While the disclosure has been described in connection with what are considered the exemplary embodiments, it is understood that this disclosure is not limited to the disclosed embodiments but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.
Number | Date | Country | Kind |
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110105413 | Feb 2021 | TW | national |