NL2023264B1 - A horizontal axis wind turbine and method for generating electrical energy - Google Patents

A horizontal axis wind turbine and method for generating electrical energy Download PDF

Info

Publication number
NL2023264B1
NL2023264B1 NL2023264A NL2023264A NL2023264B1 NL 2023264 B1 NL2023264 B1 NL 2023264B1 NL 2023264 A NL2023264 A NL 2023264A NL 2023264 A NL2023264 A NL 2023264A NL 2023264 B1 NL2023264 B1 NL 2023264B1
Authority
NL
Netherlands
Prior art keywords
turbine unit
wind turbine
turbine
diameter
wind
Prior art date
Application number
NL2023264A
Other languages
Dutch (nl)
Inventor
Lambert Sjoerd Kiezebrink Popke
Van Veldhuizen Gerrit
Erik Van Der Schee William
Original Assignee
Dutch Ventus Ip B V
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Dutch Ventus Ip B V filed Critical Dutch Ventus Ip B V
Priority to NL2023264A priority Critical patent/NL2023264B1/en
Application granted granted Critical
Publication of NL2023264B1 publication Critical patent/NL2023264B1/en

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03D—WIND MOTORS
    • F03D1/00—Wind motors with rotation axis substantially parallel to the air flow entering the rotor 
    • F03D1/04—Wind motors with rotation axis substantially parallel to the air flow entering the rotor  having stationary wind-guiding means, e.g. with shrouds or channels
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03D—WIND MOTORS
    • F03D1/00—Wind motors with rotation axis substantially parallel to the air flow entering the rotor 
    • F03D1/06—Rotors
    • F03D1/0608—Rotors characterised by their aerodynamic shape
    • F03D1/0633—Rotors characterised by their aerodynamic shape of the blades
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05B—INDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G
    • F05B2240/00—Components
    • F05B2240/20—Rotors
    • F05B2240/33—Shrouds which are part of or which are rotating with the rotor
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/70—Wind energy
    • Y02E10/72—Wind turbines with rotation axis in wind direction

Landscapes

  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Wind Motors (AREA)

Abstract

A horizontal axis wind turbine comprises a turbine unit, a turbine unit supporting frame, a generator configured for generating electrical energy, and a yaw bearing mechanism. The 5 turbine unit is supported on one or more bearings by the turbine unit supporting frame. The turbine unit is rotatable about a horizontal rotation axis to drive the generator in a direction of rotation.

Description

P33917NLO0
A HORIZONTAL AXIS WIND TURBINE AND METHOD FOR GENERATING ELECTRICAL
ENERGY The present invention relates to a horizontal axis wind turbine.
Inthe art horizontal wind turbines are known of a type comprising a turbine unit, a turbine unit supporting frame, a generator configured for generating electrical energy, and a yaw bearing mechanism. The turbine unit is supported on one or more bearings by the turbine unit supporting frame and is rotatable about a horizontal rotation axis to drive the generator in a direction of rotation to generate electrical energy. The yaw bearing mechanism is configured for mounting the turbine unit supporting frame to a support structure such that the turbine unit supporting frame is rotatable about a Z-axis. An example of such a horizontal wind turbine is shown in WO2015/190916.
It is desirable to develop horizontal wind turbines of this type for use as urban wind turbines, e.g. to be placed on top of buildings, e.g. within cities, in industrial zones, on farms, etc. During actual operation the wind obviously varies from time to time. Whilst at locations close to a shoreline wind is usually quite strong, more inland locations have a yearly average wind speed that is much lower. Existing urban wind turbine designs show low overall efficiency, especially at locations having mostly low wind speeds. Another issue is that existing urban wind turbine designs are prone to produce undesirable noise.
The invention aims to provide measures that remedy one or more of these drawbacks, or at least provide an improvement over existing turbines of this type.
The invention provides a horizontal axis wind turbine according to claim 1.
The turbine unit comprises: - a central hub arranged on the horizontal rotation axis R, the central hub having a front end and a rear end, the central hub having an exterior hub surface, - a plurality of rigid twisted blades, and - an outer tubular shroud having a front end and a rear end, an inner shroud surface, an inner diameter defined by said inner shroud surface, and an outer shroud surface.
2.
For example, the turbine unit is mainly made of plastic material(s), e.g. provided with some steel reinforcement, e.g. a steel shaft through the central hub, e.g. a steel shaft through the central hub and reinforcement rods, e.g. of steel, radially outwards from the central hub through each rigid twisted blade.
Each rigid twisted blade has a leading edge, a trailing edge, a chord length between the leading edge and the trailing edge, a root end, and a tip end. The root end of each twisted blade is integral with the central hub and the tip end is integral with the outer tubular shroud so that the turbine unit is a rigid unit. For example, for production of the turbine unit use is made of a mould in which a steel reinforcement assembly is placed, with plastic material being introduced into the mould so as to mold the rigid unit. The leading edge and the trailing edge of each blade adjoin the outer tubular shroud. The leading edge and the trailing edge also adjoin the central hub. So each rigid twisted blade is fully integral with the outer shroud and with the central hub, allowing optimal distribution of forces within the structure of the turbine unit.
Each rigid twisted blade has a first main surface and an opposed second main surface. One could also identify these surfaces as an upper surface and a lower surface from the perspective of an airplane wing. Each of said first main surface and second main surface extends from the leading edge to the trailing edge of the blade. Seen in the direction of rotation of the rotatable turbine unit during operation, the first main surface precedes or is ahead of the second main surface.
The blades have a significant chord length that is at least 1/3 of a smallest inner diameter of the outer tubular shroud. In embodiments, the chord length is at least 80% of the length of the outer shroud.
The first main surface and the second main surface of the twisted blades each have a gradual twist from the leading edge towards the trailing edge, which twist is counter to the direction of rotation during operation of the turbine.
The invention envisages that each twisted blade is embodied as an aerofoil having a profile with a mean camber line midway between the first main surface and second main surface, wherein the profile has a thickness that varies in direction of the camber line, said thickness being perpendicular to the camber line. The profile of the aerofoil is configured to produce a
3. lift force that contributes to the electricity generating rotation of the turbine unit in the direction of rotation. The invention also envisages that each twisted blade is configured such that, in a tab portion thereof that is located at the trailing edge of the twisted blade, the camber line of the blade deflects, preferably over an angle of at least 30°, in a direction counter to the direction of rotation (D), so that a second airflow which passes from the leading edge along the second main surface towards the trailing edge is deflected by said tab portion of the twisted blade into a more radial direction.
By provision, in this type of turbine, of the combination of the lift producing aerofoil profile on the one hand and the deflection of the camber line of the blade in the tab portion of the blade so that a second airflow which passes from the leading edge along the second main surface towards the trailing edge is deflected by said tab portion of the twisted blade into a more radial direction, an improved overall efficiency of the turbine can be achieved compared to prior art designs. At relatively low wind speeds the lift producing aerofoil profile is the predominant factor for improved efficiency, whereas at higher wind speeds the trailing edge deflection of the camber line improves efficiency. It is believed that on yearly basis this dual concept of the blade profile offers significant efficiency gains. In addition, noise production is minimal. The structure of the turbine unit allows for a significant dimension of the deflected tab portion of the blade, as wind forces acting thereon are absorbed into the central hub and in the outer shroud to which said tab portion is connected. It is noted that the tab portion is part of the rigid blade, and therefor rigid in itself and not movable relative to a main portion of the rigid blade. This allows for an attractive structure in view of costs for production, and avoids maintenance issues that would result from any movable tab design. In practical embodiments, the chord length is between 1 and 4 meters. For example, in a practical embodiment the chord length may be between 3 and 4 meters, whereas the inner diameter of the outer tubular shroud is between 3 and 6 meters. In practical embodiments, the deflected tab portion of the blade has a camber line length of at least 5 centimetres, e.g. at least 10 centimetres, e.g. between 12 and 25 centimetres.
In practical embodiments the smallest inner diameter of the outer tubular shroud is at least 1 meter, e.g. between 1. 5 and 6 meters, e.g. between 2 and 5 meters. These dimensions
-4- allow, for example, for use as an urban wind turbine. Of course, the same design may be used offshore, e.g. on an offshore installation, e.g. a hydrocarbon production installation, onboard a vessel, etc.
It will be appreciated that in a practical embodiment the smallest inner diameter of the outer tubular shroud may be 1.5 and 5 meters, the chord length between 1 and 4 meters, and the deflected tab portion of the blade has a camber line length of at least 5 centimetres, e.g. at least 10 centimetres, e.g. between 12 and 25 centimetres.
In a further preferred embodiment, the camber line of each rigid twisted blade has, in the tab portion, a deflection point, wherein in proximity of said deflection point the thickness of the profile locally increases so as to define in the first main surface of the blade a first airflow diverging surface that diverges from the camber line in direction to the trailing edge so that a first airflow passing over the first main surface is deflected away from the camber line. It is believed that the provision of the first airflow diverging surface further contributes to the effectiveness of the tab portion, e.g. at relatively high wind speeds.
In embodiments, the exterior hub surface at the front end of the central hub has a diameter of at most 10% of the smallest diameter of the outer tubular shroud. This allows for optimal inflow of air into the turbine unit.
In embodiments, the exterior hub surface is conical, increasing in diameter, e.g. progressively increasing in diameter, towards the rear end thereof.
In embodiments, the exterior hub surface at the front end of the central hub has a diameter of at most 10% of the smallest diameter of the outer tubular shroud, and wherein the exterior hub surface at the rear end of the central hub has a diameter of at least 25%, e.g. of about 50%, of the smallest diameter of the outer tubular shroud.
In embodiments, the outer tubular shroud has a main shroud section extending from the front end thereof towards the rear end, which main shroud section has a substantially uniform inner diameter wherein a smallest inner diameter is at least 80%, e.g. 90%, of a largest inner diameter, and wherein the outer tubular shroud has an outward flaring section adjoining the main shroud section and having a flaring inner surface, e.g. an outwardly curved flaring inner surface, adjoining the inner surface of the main shroud section at a transition.
5.
In embodiments, the main shroud section has an inner diameter that tapers from a largest inner diameter at or in proximity of the front end to a smallest diameter at said transition. In embodiments, the outward flaring section has a largest diameter at the rear end of the outer tubular shroud, which larges diameter is between 1.1 and 1.3 times the smallest inner diameter of the main shroud section, e.g. about 1.2 times. In embodiments, the rear end of the central hub, e.g. embodied as a cone, protrudes beyond the rear end of the outer tubular shroud, wherein the trailing end of each blade extends from a location at or in proximity of the protruding rear end of the central hub to a location at or in proximity of said transition to the flaring inner surface.
In embodiments, the rear end of the central hub, e.g. embodied as a cone, has a central recess that is open towards the rear of the central hub so that an annular portion of the rear end of the central hub surrounds a space, wherein the generator is at least in part received within said space.
In embodiments, the turbine unit has 3, 4, 5, 6, or 7 rigid twisted blades, e.g. 5 blades.
In embodiments, the central hub comprises a metallic shaft, e.g. a hollow shaft, e.g. the blades and the outer shroud being made of plastic material(s). In embodiments, the metallic shaft is supported on bearings at opposite ends thereof relative to the supporting frame. For example, the rear bearing is formed by one or more bearing of an electrical generator having a shaft that is integral with the metallic shaft of the central hub.
In an embodiment the central hub comprises a metallic shaft embedded in plastic that forms the body and exterior surface of the central hub, e.g. in a process of moulding the turbine unit, e.g. in a one-piece moulding of the turbine unit.
In embodiments, the turbine unit supporting frame comprises: - a lower frame member extending underneath the turbine unit, - a forward turbine supporting arm connected to the lower frame member and extending in front of the turbine unit, - a rearward turbine supporting arm connected to the lower frame member and extending behind the turbine unit, e.g. wherein the rearward turbine supporting arm is embodied as a vertical wind vane assisting the orienting of the turbine unit to the actual wind direction,
-6- wherein each of the arms supports the central hub of the turbine unit on one or more bearings, e.g. one or more bearings being part of the electrical generator.
In embodiments, the turbine unit supporting frame comprises a stabilizing wing secured to the supporting frame remote from the turbine unit, wherein in use wind directed onto the front of the turbine unit also acts on the stabilizing wing and said interaction with the stabilizing wing generates a lift force at a location that is offset from the Z axis (Z}, said lift force (L) counteracting a moment force on said yaw bearing mechanism.
In embodiments, the stabilizing wing is arranged below the turbine unit, e.g. in proximity of an outlet side thereof.
In embodiments, the stabilizing wing is mounted at an angle of attack (a) of between -5 and degrees with respect to the horizontal axis, preferably at an angle of attack (a) of between 15 2 and 10 degrees.
In embodiments, the yaw bearing mechanism is a free yaw bearing mechanism, i.e. of the type that allows a self-orienting of the turbine unit with respect to incoming wind.
In embodiments, the turbine unit supporting frame further comprises a stationary inlet shroud, arranged in front of the turbine unit and in line with the outer shroud. Generally, the inlet shroud may serve to direct the flow of air relative to the rotating turbine. In an embodiment, a rear section of the stationary inlet shroud axially overlaps with a front section of the turbine unit, the inlet shroud having a larger diameter and surrounding the front section with a gap in between.
In an embodiment, one or more stator blades are arranged within the inlet shroud, e.g. one or more stator blades each extending radially from the inlet shroud to the axis of the turbine unit. For example, the one or more stator blades each extend in a plane through the axis of the turbine unit and are stationary mounted. For example, the one or more stator blades serve to reduce any vortex motion of incoming air ahead of its introduction into the turbine unit. So, then the one or more stator blades are vortex reducing stator blades.
In an embodiment, the forward turbine supporting arm is formed as a stator blade arranged within the stationary inlet shroud, e.g. embodied as a vortex reducing stator blade.
-7- Optionally, one or more stator blades could be adjustable, e.g. pivotal about a respective axis that is radial to the horizontal axis of the turbine unit. For example, one or more stator blades could be embodied, or adjusted in position, so as to act as vortex inducing stator blades. The present invention also relates to a method for generating electrical energy wherein use is made of a horizontal axis wind turbine as disclosed herein. The present invention also relates to a turbine unit as described herein.
The present invention also relates to the production of a turbine unit as described herein. For example, for production of the turbine unit use is made of a mould in which a steel reinforcement assembly is placed, wherein a plastic material is introduced into the mould so as to mold the rigid turbine unit as a one-piece structure.
The invention will now be described with reference to the drawings. In the drawings: Fig. 1 shows in side view an exemplary embadiment of a wind turbine according to the invention mounted on a support structure, Fig. 2 shows the wind turbine of figure 1 from behind in perspective view, Fig 3a shows the wind turbine of figure 2 with the turbine unit removed, Fig. 3b shows the turbine unit of the invention from behind, Fig. 4 shows figure 3 on a larger scale, Fig. 5 shows the turbine unit of figure 3b in side view, Fig. 6 shows the turbine unit of figure 3b from the front, Fig. 7 shows the turbine unit of figure 6 at an angle, Fig. 8 shows the turbine unit of figure 3b in a sectional view, Fig. 9 shows the turbine unit of figure 3b in another sectional view, Fig. 10 shows the turbine unit of figure 3b in another sectional view, Figs. 11 - 14 illustrate the rotation of the turbine unit of figure 3b in sectional views.
With reference to the figures a horizontal axis wind turbine will be discussed, which is envisaged for instance for use as an urban wind turbine.
The wind turbine 1 comprises a turbine unit 10, a turbine unit supporting frame 60, a generator 70 that is configured for generating electrical energy, and a yaw bearing mechanism 100.
-8- The yaw bearing mechanism 100 connects the wind turbine 1 to a support structure 110, e.g. configured to be placed on a roof of a building, e.g. configured as mast, etc. The yaw bearing mechanism 100, e.g. a free yawing design, is configured for mounting the turbine unit supporting frame 60 to the support structure 100 such that the turbine unit supporting frame 60 is rotatable about a Z-axis, preferably over 360 degrees. The turbine unit supporting frame 60 comprises: - a lower frame member 61 extending underneath the turbine unit 10, - a forward turbine supporting arm 82 that is connected to the lower frame member 61 and extends in front of the turbine unit 10, - a rearward turbine supporting arm 63 that is connected to the lower frame member 61 and extends behind the turbine unit 10. In the depicted example, the rearward turbine supporting arm 63 is embodied as a vertical wind vane assisting the orienting of the turbine unit to the actual wind direction.
The turbine unit 10 comprises: - a central hub 20 arranged on a horizontal rotation axis (R), said central hub having a front end 21 and a rear end 22, said central hub having an exterior hub surface 23, - a plurality of rigid twisted blades 30, and - an outer tubular shroud 50 having a front end 51 and a rear end 52, an inner shroud surface 53, an inner diameter defined by said inner shroud surface, and an outer shroud surface 54. As preferred, the shroud 50 is not surrounded by any further shroud or the like, possibly (as here) with the exception of a stationary inlet shroud 66 overlapping a small front section of the shroud 50. Therefore, the outer shroud surface 54 guides the wind passing along the outside of the unit 10. The drawings illustrate that the turbine unit supporting frame 60 further comprises a stationary inlet shroud 66, arranged in front of the turbine unit 10 and in line with the outer shroud 50. The shroud 66 may, as shown, slightly overlap with a front section of the shroud 50, as preferred the shroud 66 surrounding said front section with an annular gap in between. The drawings illustrate that the turbine unit 10 has between 3 and 7 blades 30, e.g. 5 blades
30.
Each of the arms 62, 63 supports the central hub 20 of the turbine unit 10 on one or more bearings 64, 65, e.g. one or more bearings 65 being part of the electrical generator 70.
-9- The turbine unit 10 is rotatable about a horizontal rotation axis R to drive the generator 70 in a direction of rotation D.
The turbine unit supporting frame 60 further comprises a stabilizing wing 87 that is secured to the supporting frame 60 remote from the turbine unit 10. In use, wind directed onto the front of the turbine unit 10 also acts on the stabilizing wing 67 and said interaction with the stabilizing wing generates a lift force at a location that is offset from the Z-axis, said lift force counteracting a moment force on said yaw bearing mechanism 100. The stabilizing wing is arranged below the turbine unit 10, in proximity of an outlet side thereof. In embodiments the stabilizing wing is mounted at an angle of attack (a) of between -5 and 15 degrees with respect to the horizontal axis, preferably at an angle of attack (a) of between 2 and 10 degrees.
Each rigid twisted blade 30 has a leading edge 31, a trailing edge 32, a chord length between the leading edge and the trailing edge, a root end 34, and a tip end 35. The root end 34 of each blade is fully integral with the central hub 20 and the tip end 35 is fully integral with the outer tubular shroud 50 so that the turbine unit 10 is a rigid unit.
The leading edge 31 and the trailing edge 32 each adjoin the outer tubular shroud 50. The leading edge 31 and the trailing edge 32 also adjoin the central hub 20. Each twisted blade 30 has a first main surface 40 and an opposed second main surface 41.
Each of these first main surface 40 and second main surface 41 extends from the leading edge 31 to the trailing edge 32. Seen in the direction of rotation (D) of the turbine unit 10 during operation, the first main surface 40 precedes or is ahead of the second main surface
41. As will be appreciated one could also identify surface 40 as upper surface and surface 41 as lower surface of an aerofoil profile.
The chord length of each twisted blade 30 is at least 1/3 of a smallest inner diameter of the outer tubular shroud 50. In this embodiment the chord length is over 80% of the length of the outer shroud.
The first main surface 40 and the second main surface 41 of the twisted blades 30 each have a gradual twist from the leading edge 31 towards the trailing edge 32, which twist is counter to the direction of rotation D.
-10- Each twisted blade 30 is embodied as an aerofoil having a profile with a mean camber line midway between the first main surface 40 and second main surface 41. As can be seen the profile has a thickness that varies in direction of the camber line. Herein the thickness is perpendicular to the camber line.
As will be appreciated by the skilled person the profile of the aerofoil of each blade is configured to produce a lift force that contributes to the rotation of the turbine unit in the electricity producing direction of rotation D.
As can be seen, the camber line of each blade 30 deflects in a tab portion 45 of the blade that is located at the trailing edge 32 of the twisted blade. This deflection is prominent, and preferably is over an angle of at least 30°. The deflection is in a direction counter to the direction of rotation D. The deflected tab portion 45 of the blade 30 acts on the air in such a manner that a second airflow which passes from the leading edge 31 along the second main surface 41 towards the trailing edge 32 is deflected by the tab portion 45 of the twisted blade into a more radial direction, counter to the direction of rotation D.
It is also shown that in the tab portion 45 the camber line of the blade 30 has a deflection point, wherein in proximity of said deflection point the thickness of the profile locally increases so as to define in the first main surface 40 of the blade a first airflow diverging surface 46 that diverges from the camber line in direction to the trailing edge 32 so that a first airflow passing over the first main surface 40 is deflected away from the camber line at said location.
In the depicted design of the turbine unit 10, whereof all parts are shown to scale in the drawings, the outer tubular shroud has an inlet diameter of 2.73 metres.
In a practical embodiment the deflected tab portion 45 of the blade has a camber line length of at least 5 centimetres, e.g. at least 10 centimetres, e.g. between 12 and 25 centimetres. So, in general terms, the portion 45 may be very substantial top achieve an improved efficiency. As explained the integration of the blades 30, including the tab portion 45, into the structure of the unit 10 allows for the large wind forces acting on the portion 45 to be absorbed by the entire unit 10.
In embodiments the smallest inner diameter of the outer tubular shroud is at least 1 meter, e.g. between 1. 5 and 5 meters, e.g. between 2 and 3 meters, here of 2.73 meters.
-11- The drawings illustrate that the exterior hub surface 23 at the front end 21 of the central hub 20 has a diameter of at most 10% of the smallest diameter of the outer tubular shroud 50. At the same time the generator 70 is placed at the rear of the turbine, so that inflow of air is not impaired by the nose of the hub 20 and/or the presence of a generator 70 that would disturb the inflow of air.
The drawings illustrate that the exterior hub surface 23 is conical in shape, increasing in diameter, here progressively increasing in diameter, towards the rear end thereof.
The drawings illustrate that the exterior hub surface 23 at the front end 21 of the central hub has a diameter of at most 10% of the smallest diameter of the outer tubular shroud 50. It is also shown that the exterior hub surface at the rear end 22 of the central hub 20 has a diameter of at least 25%, here of about 50%, of the smallest diameter of the outer tubular shroud 50. This, as shown here, allows to position the generator 70 at the rear end of the hub on the axis R, so as to not interfere with the flow of air.
The drawings illustrate that the outer tubular shroud 50 has a main shroud section 56 extending from the front end 51 thereof towards the rear end.
This main shroud section 56 20 has a substantially uniform inner diameter, wherein a smallest inner diameter is at least 90% of a largest inner diameter.
As shown here, and as preferred, the inner diameter of the section 56 lightly tapers inward in direction to the rear end.
The drawings illustrate that the outer tubular shroud 50 has an outward flaring section 57 adjoining the main shroud section 56 and having a flaring inner surface 58, here an outwardly curved flaring inner surface 58, adjoining the inner surface of the main shroud section 56 at a transition 59. The drawings illustrate that the main shroud section 56 has an inner diameter that tapers from alargest inner diameter at or in proximity of the front end to a smallest diameters at said transition 59. The drawings illustrate that the outward flaring section 57 has a largest diameter at the rear end of the outer tubular shroud 50. This largest diameter is between 1.1. and 1.3. times the smallest inner diameter of the main shroud section, e.g. about 1.2 times.
-12- The drawings illustrate that the rear end of the central hub 20 protrudes axially beyond the rear end of the outer tubular shroud 50. It is also shown that the trailing end of each blade 30 extends from a location at or in proximity of the protruding rear end of the central hub 20 to a location at or in proximity of said transition 59 to the flaring inner surface 57.
The drawings illustrate that the rear end of the central hub 20 has a central recess 24 that is open towards the rear so that an annular portion of the rear end of the central hub 20 surrounds a space. The generator 70 is at least in part received within said space.
Itis illustrated that the turbine unit is mainly made of plastic material(s), as is preferred, e.g. moulded as a one-piece structure, e.g. moulded about a steel reinforcement structure.
A metallic, e.g. steel, shaft 24a extends through the central hub 20, e.g. a hollow shaft 24a.
The shaft 24a is supported on the bearings 64, 65, e.g. the shaft 24a being connected in line with a shaft of generator 70.
It is illustrated that there is no transmission between the unit 10 and the generator 70.
A brake device may be provided to brake the unit 10, e.g. to lock the unit 10 for performing maintenance or in other circumstance. For example, the brake device is located at least in part in central recess 24 and/or integrated with the generator.
The central hub 20, the rigid twisted blades, and the outer shroud are preferably made of plastic material, e.g. moulded as a one-piece structure, e.g. with a metal reinforcement assembly embedded therein.
Figures 8, 9, for example, illustrate that one or more reinforcement rods 25, e.g. of metal, e.g. of steel, extend from the central hub, e.g. attached to the shaft 24, through each twisted blade. For example, one or more reinforcement hoops, e.g. of metal, e.g. of steel, are integrated in the outer shroud, with the one or more rods 25 being secured to a respective reinforcement hoop.

Claims (23)

-13- CONCLUSIES-13- CONCLUSIONS 1. Een windturbine met een horizontale as (1), omvattende een turbine-eenheid (10), een turbine-eenheiddraagframe (60), een generator (70) ingericht om elektrische energie te genereren, en een zwenklagermechanisme (100), waarbij de turbine-eenheid (10) op één of meer lagers (64,65) door het turbine-eenheiddraagframe (60) is ondersteund, waarbij de turbine-eenheid (10) roteerbaar is om een horizontale rotatieas (R) in een rotatierichting (D) om de generator (70) aan te drijven, waarbij het zwenklagermechanisme (100) is ingericht voor het zodanig aan een draagstructuur (110) bevestigen van het turbine-eenheiddraagframe (60) dat het turbine- eenheiddraagframe (80) roteerbaar is om een Z-as (Z), waarbij de turbine-eenheid omvat: - een centrale naaf (20) gelegen op de horizontale rotatie-as (R), waarbij de centrale naaf een vooruiteinde (21) en een achteruiteinde (22) heeft, waarbij de centrale naaf een buitenste naafoppervlak (23) heeft, - meerdere rigide getordeerde bladen (30), en - een buitenste buisvormige mantel (50) die een vooruiteinde (51) en een achteruiteinde (52) heeft, een binnenste manteloppervlak (53), een binnenste diameter gedefinieerd door het binnenste manteloppervlak (53), en een buitenste manteloppervlak (54), waarbij elk rigide getordeerd blad {30) een voorrand (31), een achterrand (32), een koordelengte tussen de voorrand en achterrand, een voetuiteinde (34) en een tipuiteinde (35) heeft, waarbij het voetuiteinde (34) integraal is met de centrale naaf (20) en het tipuiteinde (35) integraal is met de buitenste buisvormige mantel (50) zodat de windturbine-eenheid (10) rigide is, waarbij de voorrand (31) en de achterrand (32) op de buitenste buisvormige mantel (50) aansluiten, en waarbij de voorrand (31) en de achterrand (32} op de centrale naaf (32) aansluiten, waarbij elk getordeerd blad (30) een eerste hoofdoppervlak (40) en een tegenovergelegen tweede hoofdoppervlak (41) heeft, waarbij elk van het eerste hoofdoppervlak en tweede hoofdoppervlak zich van de voorrand (31) naar de achterrand (32) uitstrekt, waarbij - gezien in de rotatierichting (D) van de roteerbare turbine-eenheid tijdens bedrijf - het eerste hoofdoppervlak (40) voorafgaat aan het tweede hoofdoppervlak (41),A wind turbine with a horizontal axis (1), comprising a turbine unit (10), a turbine unit support frame (60), a generator (70) arranged to generate electrical energy, and a swing bearing mechanism (100), the turbine unit (10) is supported on one or more bearings (64,65) by the turbine unit cradle (60), the turbine unit (10) being rotatable about a horizontal axis of rotation (R) in a direction of rotation (D) to drive the generator (70), the swing bearing mechanism (100) being configured to attach the turbine unit support frame (60) to a support structure (110) such that the turbine unit support frame (80) is rotatable about a Z- shaft (Z), the turbine unit comprising: - a central hub (20) located on the horizontal axis of rotation (R), the central hub having a front end (21) and a rear end (22), the central hub hub has an outer hub surface (23), - multiple rigid twisted blades (30), and - one outer tubular shell (50) having a front end (51) and a rear end (52), an inner shell surface (53), an inner diameter defined by the inner shell surface (53), and an outer shell surface (54), each rigid twisted blade {30) has a leading edge (31), a trailing edge (32), a chord length between the leading edge and trailing edge, a foot end (34) and a tip end (35), the foot end (34) being integral with the central hub (20) and the tip end (35) is integral with the outer tubular shell (50) so that the wind turbine unit (10) is rigid, with the leading edge (31) and trailing edge (32) on the outer tubular shell (50) and wherein the leading edge (31) and the trailing edge (32} abut the center hub (32), each twisted blade (30) having a first major surface (40) and an opposite second major surface (41), each of the first major surface and the second major surface are shown h extends from the front edge (31) to the rear edge (32), wherein - viewed in the rotational direction (D) of the rotatable turbine unit during operation - the first major surface (40) precedes the second major surface (41), -14 - waarbij een koordelengte van elk getordeerd blad (30) ten minste 1/3 bedraagt van een kleinste binnendiameter van de buitenste buisvormige mantel (50), waarbij het eerste hoofdoppervlak (40) en het tweede hoofdoppervlak (41) van de getordeerde bladen (30) elk een geleidelijke torsie hebben van de voorrand (31) naar de achterrand (32), welke torsie tegengesteld is aan de rotatierichting (D), waarbij elk getordeerd blad (30) is belichaamd als een vleugel met een profiel dat een welvingslijn in het midden tussen het eerste oppervlak (40) en het tweede oppervlak (42) heeft, waarbij het profiel een dikte heeft die in de richting van de welvingslijn varieert, waarbij de dikte loodrecht op de welvingslijn staat, waarbij het profiel van de vleugel is ingericht om een opwaartse kracht te produceren die bijdraagt aan de rotatie van de turbine-eenheid (10) in de rotatierichting (D), waarbij, in een lipgedeelte (45) dat zich aan de achterrand van het getordeerde blad (30) bevindt, de welvingslijn afbuigt, bij voorkeur over een hoek van ten minste 30°, in een richting tegengesteld aan de rotatierichting (D), zodat een tweede luchtstroming die van de voorrand langs het tweede hoofdoppervlak (41) naar de achterrand (32) passeert door het lipgedeelte van het getordeerde blad (30) naar een meer radiale richting wordt afgebogen.-14 - wherein a chord length of each twisted blade (30) is at least 1/3 of a smallest inner diameter of the outer tubular sheath (50), the first major surface (40) and the second major surface (41) of the twisted blades (30) each have a gradual torque from the leading edge (31) to the trailing edge (32), which torque is opposite to the direction of rotation (D), each twisted blade (30) being embodied as a wing with a profile forming a warp line in the middle between the first surface (40) and the second surface (42), the profile having a thickness that varies in the direction of the warp line, the thickness being perpendicular to the warp line, the profile of the wing being arranged to produce an upward force that contributes to the rotation of the turbine unit (10) in the direction of rotation (D), wherein, in a lip portion (45) located on the trailing edge of the twisted blade (30), the curvature line deflects, preferably at an angle of at least 30 °, in a direction opposite to the direction of rotation (D), so that a second air flow passing from the front edge along the second major surface (41) to the rear edge (32) passes through the lip portion from the twisted blade (30) is deflected to a more radial direction. 2. Windturbine volgens conclusie 1, waarbij de koordelengte tussen 1 en 4 meter is.Wind turbine according to claim 1, wherein the chord length is between 1 and 4 meters. 3. Windturbine volgens conclusie 1 of 2, waarbij het afgebogen lipgedeelte (45) van het getordeerde blad (30) een welvingslijnlengte van ten minste 5 centimeter heeft, bijv. ten minste 10 centimeter, bijv. tussen 12 en 25 centimeter.The wind turbine of claim 1 or 2, wherein the deflected lip portion (45) of the twisted blade (30) has a warp line length of at least 5 centimeters, e.g. at least 10 centimeters, e.g. between 12 and 25 centimeters. 4. Windturbine volgens één of meer van de conclusies 1-3, waarbij de kleinste binnendiameter van de buitenste buisvormige mantel (50) ten minste 1 meter, bijv. tussen 1.5 en 5 meter, bijv. tussen 2 en 3 meter is.Wind turbine according to one or more of the claims 1-3, wherein the smallest inner diameter of the outer tubular jacket (50) is at least 1 meter, e.g. between 1.5 and 5 meters, e.g. between 2 and 3 meters. 5. Windturbine volgens één of meer van de conclusies 1-4, waarbij in het lipgedeelte (45) de welvingslijn van het blad een afbuigpunt heeft, en waarbij nabij het afbuigpunt de dikte van het profiel lokaal toeneemt om zo in het eerste hoofdoppervlak (40) van het blad een eerste luchtstromingsdivergerend oppervlak te definiëren dat van de welvingslijn in de richting van de achterrand (32) divergeert, zodat een eerste luchtstroming die over het eerste hoofdoppervlak passeert van de welvingslijn vandaan wordt afgebogen.Wind turbine according to one or more of the claims 1-4, wherein in the lip portion (45) the curvature line of the blade has a deflection point, and wherein near the deflection point the thickness of the profile increases locally so as to fit into the first major surface (40 ) of the blade, define a first airflow diverging surface that diverges from the warp line toward the trailing edge (32) so that a first air flow passing over the first major surface is deflected away from the warp line. -15--15- 6. Windturbine volgens één of meer van de conclusies 1-5, waarbij het buitenste naafoppervlak (23) aan het vooruiteinde van de centrale naaf een diameter van ten hoogste 10% van de kleinste diameter van de buitenste buisvormige mantel (50) heeft.A wind turbine according to any of claims 1 to 5, wherein the outer hub surface (23) at the front end of the central hub has a diameter of at most 10% of the smallest diameter of the outer tubular shell (50). 7. Windturbine volgens één of meer van de conclusies 1-6, waarbij het buitenste naafoppervlak (23) conisch is, toenemend in diameter, bijv. progressief toenemend in diameter, in de richting van het achteruiteinde daarvan.A wind turbine according to any one of claims 1 to 6, wherein the outer hub surface (23) is conical, increasing in diameter, e.g., progressively increasing in diameter, towards the rear end thereof. 8. Windturbine volgens één of meer van de conclusies 1-7, waarbij het buitenste naafoppervlak (23) aan het vooruiteinde van de centrale naaf een diameter van ten hoogste 10% van de kleinste diameter van de buitenste buisvormige mantel (50) heeft, en waarbij het buitenste naafoppervlak aan het achteruiteinde van de centrale naaf een diameter van ten minste 25%, bijv. van ongeveer 50%, van de kleinste diameter van de buitenste buisvormige mantel heeft.The wind turbine of any one of claims 1 to 7, wherein the outer hub surface (23) at the front end of the central hub has a diameter of at most 10% of the smallest diameter of the outer tubular shell (50), and wherein the outer hub surface at the rear end of the central hub has a diameter of at least 25%, e.g., about 50%, of the smallest diameter of the outer tubular shell. 9. Windturbine volgens één of meer van de conclusies 1-8, waarbij de buitenste buisvormige mantel (50) een hoofdmantelsectie (56) heeft die zich van het vooruiteinde daarvan uitstrekt in de richting van de het achteruiteinde, welke hoofdmantelsectie een in hoofdzaak uniforme binnendiameter heeft waarbij een kleinste binnendiameter ten minste 80%, bijv. 90%, van een grootste binnendiameter is, en waarbij de buitenste buisvormige mantel een naar buiten uitwaaierende sectie (57) heeft die op de hoofdmantelsectie (56) aansluit en een uitwaaierend binnenoppervlak heeft, bijv. een uitwaarts gewelfd uitwaaierend binnenoppervlak, dat bij een transitie aansluit op het binnenoppervlak van de hoofdmantelsectie.A wind turbine according to any one of claims 1 to 8, wherein the outer tubular shell (50) has a main casing section (56) extending from its front end towards the rear end, said main casing section having a substantially uniform inner diameter. wherein a smallest inner diameter is at least 80%, e.g. 90%, of a largest inner diameter, and wherein the outer tubular jacket has an outwardly fanned-out section (57) that joins the main jacket section (56) and has a fanned-out inner surface, e.g., an outwardly arched, fanning-out inner surface that joins the inner surface of the main casing section in transition. 10. Windturbine volgens één of meer van de conclusies 1-9, bij voorkeur volgens conclusie 9, waarbij de hoofdmantelsectie (56) een binnendiameter heeft die versmalt van een grootste binnendiameter aan of nabij het vooruiteinde naar een kleinste diameter bij de transitie.A wind turbine according to any one of claims 1 to 9, preferably according to claim 9, wherein the main casing section (56) has an inner diameter that narrows from a largest inner diameter at or near the front end to a smallest diameter at the transition. 11. Windturbine volgens conclusie 9 en 10, waarbij de naar buiten uitwaaierende sectie (57) een grootste diameter heeft aan een achteruiteinde van de buitenste buisvormige mantel (50), welke grootste diameter tussen 1.1 en 1.3 maal de kleinste binnendiameter van de hoofdmantelsectie is, bijv. ongeveer 1.2 maal.A wind turbine according to claims 9 and 10, wherein the outwardly fanning section (57) has a largest diameter at a rear end of the outer tubular shell (50), which largest diameter is between 1.1 and 1.3 times the smallest inner diameter of the main casing section, e.g. about 1.2 times. 12. Windturbine volgens één of meer van de conclusies 1-11, waarbij het achteruiteinde van de centrale naaf (20) voorbij het achteruiteinde van de buitenste buisvormige mantelThe wind turbine of any one of claims 1 to 11, wherein the rear end of the center hub (20) is beyond the rear end of the outer tubular shell -16 - uitsteekt, en waarbij het achteruiteinde (32) van elk getordeerd blad (30) zich van een locatie aan of nabij het uitstekende achteruiteinde van de centrale naaf uitstrekt naar een locatie bij of nabij de transitie naar het uitwaaierende binnenoppervlak.16 protruding, and wherein the rear end (32) of each twisted blade (30) extends from a location at or near the protruding rear end of the center hub to a location at or near the transition to the inner fanned surface. 13. Windturbine volgens één of meer van de conclusies 1-12, waarbij het achteruiteinde van de centrale naaf een centrale verdieping (24) heeft die open is in de richting van de achterzijde, zodat een ringvormig gedeelte van het achteruiteinde van de centrale naaf een ruimte omgeeft, en waarbij de generator (70) ten minste gedeeltelijk binnen deze ruimte is opgenomen.A wind turbine according to any one of claims 1 to 12, wherein the rear end of the central hub has a central recess (24) that is open towards the rear so that an annular portion of the rear end of the central hub has a space, and wherein the generator (70) is at least partially contained within this space. 14. Windturbine volgens één of meer van de conclusies 1-13, waarbij de turbine-eenheid (10) tussen 3 en 7 bladen heeft, bijv. 5 bladen.Wind turbine according to one or more of claims 1-13, wherein the turbine unit (10) has between 3 and 7 blades, e.g. 5 blades. 15. Windturbine volgens één of meer van de conclusies 1-14, waarbij de centrale naaf (20) een metalen holle schacht (24) omvat, bijv. waarbij de bladen en buitenste mantel van kunststof materia(a)l{en) zijn gemaakt.A wind turbine according to any one of claims 1 to 14, wherein the central hub (20) comprises a metal hollow shaft (24), e.g. the blades and outer shell are made of plastic material (s). . 16. Windturbine volgens één or meer van conclusies 1-15, waarbij het turbine- eenheiddraagframe omvat: - een onderste frame-element (61) dat zich onder de turbine-eenheid (10) uitstrekt, - een voorste turbinedraagarm (62) die is verbonden met het onderste frame-element (61) en zich voor de turbine-eenheid uitstrekt. - een achterste turbinedraagarm (63) die is verbonden met het onderste frame-element (61) en zich achter de turbine-eenheid uitstrekt, bijv. waarbij de achterste turbinedraagarm is belichaamd als een verticale windvaan die helpt bij het oriënteren van de turbine-eenheid op de actuele windrichting, waarbij elk van de armen (82,83) de centrale naaf (20) van de turbine-eenheid ondersteunt op één of meer lagers (64,65), bijv. waarbij de één of meer lagers onderdeel zijn van de elektrische generator (70).A wind turbine according to any one or more of claims 1-15, wherein the turbine unit support frame comprises: - a lower frame member (61) extending below the turbine unit (10), - a front turbine support arm (62) which is connected to the lower frame member (61) and extending in front of the turbine unit. - a trailing rear turbine arm (63) connected to the lower frame member (61) and extending behind the turbine unit, e.g., the trailing rear turbine arm being embodied as a vertical wind vane that aids in the orientation of the turbine unit on the current wind direction, each of the arms (82,83) supporting the central hub (20) of the turbine unit on one or more bearings (64,65), e.g. the one or more bearings being part of the electric generator (70). 17. Windturbine volgens één van de conclusies 1-18, waarbij het turbine- eenheiddraagframe een stabiliserende vleugel (67) omvat die is bevestigd aan het draagframe (60) op afstand van de turbine-eenheid, waarbij in bedrijf wind gericht op de voorzijde van de turbine-eenheid ook inwerkt op de stabiliserende vleugel (67) en de interactie met de stabiliserende vleugel een opwaartse kracht opwekt op een locatie die ten opzichte van de Z-as is verschoven, waarbij de opwaartse kracht (L) een momentkracht op het zwenklagermechanisme tegenwerkt.The wind turbine of any one of claims 1 to 18, wherein the turbine unit support frame comprises a stabilizing wing (67) attached to the support frame (60) remote from the turbine unit, with wind directed to the front of the turbine unit in operation. the turbine unit also acts on the stabilizing wing (67) and interacting with the stabilizing wing creates an upward force at a location offset from the Z axis, where the upward force (L) is a moment force on the swing bearing mechanism opposes. -17 --17 - 18. Windturbine volgens conclusie 17, waarbij de stabiliserende vleugel (67) is aangebracht onder de windturbine-eenheid, bijv. nabij een uitlaatzijde daarvan.A wind turbine according to claim 17, wherein the stabilizing wing (67) is arranged under the wind turbine unit, e.g. near an outlet side thereof. 19. Windturbine volgens conclusie 17 of 18, waarbij de stabiliserende vleugel (67) onder een invalshoek (a) van tussen -5 en 15 graden ten opzichte van de horizontale as is bevestigd, bij voorkeur onder een invalshoek (a) van tussen 2 en 10 graden.Wind turbine according to claim 17 or 18, wherein the stabilizing wing (67) is mounted at an angle of incidence (α) of between -5 and 15 degrees from the horizontal axis, preferably at an angle of incidence (α) of between 2 and 10 degrees. 20. Windturbine volgens één van de conclusies 1-19, waarbij het zwenklagermechanisme (100) een vrij zwenklagermechanisme is, bijv. van het type die een zelf-oriéntatie van de turbine-eenheid ten opzichte van inkomende wind mogelijk maakt.A wind turbine according to any one of claims 1-19, wherein the swing bearing mechanism (100) is a free swing bearing mechanism, e.g. of the type that allows self-orientation of the turbine unit with respect to incoming wind. 21. Windturbine volgens één van de conclusies 1-20, waarbij het turbine- eenheiddraagframe (60) verder een stationaire inlaatmantel (66) omvat, aangebracht voor de turbine-eenheid (10) en op één lijn met de buitenste mantel (50), bijv. waarbij één of meer statorbladen (82) zijn aangebracht binnen in de inlaatmantel, bijv. waarbij de één of meer statorbladen zich radiaal uitstrekken van de inlaatmantel naar de as van de turbine-eenheid.The wind turbine of any of claims 1-20, wherein the turbine unit support frame (60) further comprises a stationary inlet shroud (66) disposed in front of the turbine unit (10) and aligned with the outer shroud (50), e.g. wherein one or more stator blades (82) are disposed within the inlet shroud, e.g. wherein the one or more stator blades extend radially from the inlet shroud to the axis of the turbine unit. 22. Windturbine volgens conclusies 16 en 21, waarbij de voorwaartse turbinedraagarm (62) is gevormd als een statorblad aangebracht binnen de stationaire inlaatmantel.The wind turbine of claims 16 and 21, wherein the forward turbine support arm (62) is formed as a stator blade disposed within the stationary inlet shroud. 23. Een werkwijze voor het genereren van elektrische energie waarbij gebruik wordt gemaakt van een windturbine met horizontale as volgens één of meer van de voorgaande conclusies.A method of generating electrical energy using a horizontal axis wind turbine according to any one of the preceding claims.
NL2023264A 2019-06-05 2019-06-05 A horizontal axis wind turbine and method for generating electrical energy NL2023264B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
NL2023264A NL2023264B1 (en) 2019-06-05 2019-06-05 A horizontal axis wind turbine and method for generating electrical energy

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NL2023264A NL2023264B1 (en) 2019-06-05 2019-06-05 A horizontal axis wind turbine and method for generating electrical energy

Publications (1)

Publication Number Publication Date
NL2023264B1 true NL2023264B1 (en) 2020-12-22

Family

ID=67660431

Family Applications (1)

Application Number Title Priority Date Filing Date
NL2023264A NL2023264B1 (en) 2019-06-05 2019-06-05 A horizontal axis wind turbine and method for generating electrical energy

Country Status (1)

Country Link
NL (1) NL2023264B1 (en)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030137149A1 (en) * 2001-10-29 2003-07-24 Northrup G. William Segmented arc generator
WO2015190916A1 (en) 2014-06-10 2015-12-17 Ventus Nautilus Holding B.V. Device for converting kinetic energy of a flowing medium to electrical energy
WO2016085858A1 (en) * 2014-11-26 2016-06-02 Phillips Roger Gordon High-efficiency wind generator

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030137149A1 (en) * 2001-10-29 2003-07-24 Northrup G. William Segmented arc generator
WO2015190916A1 (en) 2014-06-10 2015-12-17 Ventus Nautilus Holding B.V. Device for converting kinetic energy of a flowing medium to electrical energy
WO2016085858A1 (en) * 2014-11-26 2016-06-02 Phillips Roger Gordon High-efficiency wind generator

Similar Documents

Publication Publication Date Title
CN102032099B (en) Systems and methods of assembling a rotor blade extension for use in a wind turbine
US4408958A (en) Wind turbine blade
EP2341245B1 (en) Apparatus for increasing lift on wind turbine blade
JP5043830B2 (en) Vertical axis wind turbine
CN100390406C (en) Improved turbine
US7837442B2 (en) Root sleeve for wind turbine blade
JP7030711B2 (en) Floating wind turbine with vertical axis twin turbine with improved efficiency
CN101918707B (en) Wind turbine rotor with the vertical rotation axis
KR20130112787A (en) Flexible flap arrangement for a wind turbine rotor blade
US20210262435A1 (en) Fluidic turbine structure
US20200182220A1 (en) Fluid-redirecting structure
US20040156723A1 (en) Vertical axis windmill
US20190257285A1 (en) Arched rib for a turbine
NL2023264B1 (en) A horizontal axis wind turbine and method for generating electrical energy
US20130224039A1 (en) Rotor for Vertical Wind Power Station
KR102067026B1 (en) Vertical wind turbine with auxiliary blade
US10316824B2 (en) Camber changing and low drag wing for vertical axis wind turbine
KR100979177B1 (en) Wind-turbine apparatus
NL2021921B1 (en) Horizontal axis wind turbine with stabilizing wing
KR101136546B1 (en) Wind-collecting type wind power generator
NL2025800B1 (en) A horizontal axis wind turbine and method for generating electrical energy
US20130156596A1 (en) Airfoil Design for Wakeless Wind Turbine Tower Structures
US11473559B2 (en) Hinged wind turbine blade defining an angle in a flap-wise direction
EP3847368A1 (en) Fluidic turbine structure
JP2021017823A (en) Wind power generation device

Legal Events

Date Code Title Description
MM Lapsed because of non-payment of the annual fee

Effective date: 20220701