Flow guiding device for a wind turbine rotor blade and a wind turbine rotor blade

Abstract

A flow guiding device for a wind turbine rotor blade is provided, which includes a first part and a second part. The first part includes a rear surface for facing the surface of the wind turbine rotor blade. The second part is connected to the first part and extends along a length in a first direction from the first part. The second part includes a top surface angled at an angle between 90° and 180° relative to the rear surface of the first part. The second part includes a plurality of corrugations extending along the length. The second part also includes a plurality of openings configured to allow flow to pass through the second part. A wind turbine and a wind turbine rotor blade are also disclosed, both of which include the flow guiding device for the wind turbine rotor blade.

Description

Technical Field

[0001] The following relates to a flow guiding device for a wind turbine rotor blade and a wind turbine rotor blade, and more particularly to a flow guiding device that provides favorable aerodynamic characteristics for a wind turbine. Background Art

[0002] In a wind turbine rotor blade, the blade generally includes an airfoil portion located distally of the shoulder of the blade. The root portion attaches the blade to the rotor. At the portion of the blade between the root and the shoulder, the airfoil generally cannot extract power from the wind. This is because the shape of the blade in this area is restricted by structure and transportation. The blade structure in the root and / or transition area is more cylindrical and is restricted in chord. Therefore, this area does not generate as much lift as the outer airfoil. Additional devices are used to compensate for this lack of lift attached to the blade in this area. However, such additional devices generally increase the drag on the blade. Due to the increased efficiency and output of these additional devices, this reduction in drag is generally acceptable in the art. Summary of the Invention

[0003] One aspect relates to a flow guiding device for a wind turbine rotor blade, comprising: a first portion including a rear surface for facing the surface of the wind turbine rotor blade; and a second portion connected to the first portion and extending from the first portion along a length in a first direction, the second portion including a top surface angled at an angle between 90° and 180° relative to the rear surface of the first portion; wherein the second portion includes a plurality of corrugations extending along the length, and wherein the second portion further includes a plurality of openings configured to allow flow to pass through the second portion.

[0004] In an exemplary embodiment, the first portion and the second portion are made of a single piece. Additionally, a transition portion is arranged between the first portion and the second portion, and wherein a plurality of corrugations extend into the transition portion. Additionally, the top surface of the second portion is arranged at an angle between 110° and 160° relative to the rear surface of the first portion. The plurality of openings may include a plurality of elongated slits provided across the width of the second portion, the plurality of elongated slits extending in the first direction. Alternatively or additionally, each of the plurality of openings includes a plurality of elongated slits extending perpendicular to the first direction. The plurality of openings may also include multiple rows of elongated slits. Alternatively or additionally, the plurality of openings includes a plurality of elongated slits extending perpendicular to the first direction, each elongated slit having an inverted V shape. The plurality of openings may also include multiple rows of elongated slits.

[0005] On the other hand, it relates to a wind turbine rotor blade, comprising: a span direction; a root portion; a shoulder; and a wind turbine rotor blade fairing, the wind turbine rotor blade fairing comprising: a first portion including a rear surface for facing the surface of the wind turbine rotor blade; and a second portion connected to the first portion and extending from the first portion along a length in a first direction, the second portion including a top surface angled at an angle between 90° and 180° relative to the rear surface of the first portion; wherein the second portion includes a plurality of corrugations extending along the length, wherein the second portion further includes a plurality of openings configured to allow flow through the second portion, wherein the wind turbine rotor blade fairing is connected to the blade such that the rear surface of the first portion faces the surface of the blade, and wherein the wind turbine rotor blade fairing is connected to the wind turbine rotor blade between the root portion and the shoulder in the span direction.

[0006] In an exemplary embodiment, the first portion and the second portion are made as a single piece. Additionally, a transition portion is arranged between the first portion and the second portion, and wherein the plurality of corrugations extend into the transition portion. Additionally, the top surface of the second portion is arranged at an angle between 110° and 160° relative to the rear surface of the first portion. The plurality of openings may include a plurality of elongated slits provided across the width of the second portion, the plurality of elongated slits extending in the first direction. Alternatively or additionally, each of the plurality of openings includes a plurality of elongated slits extending perpendicular to the first direction. The plurality of openings may also include multiple rows of elongated slits. Alternatively or additionally, the plurality of openings include a plurality of elongated slits extending perpendicular to the first direction, each elongated slit having an inverted V shape. The plurality of openings may also include multiple rows of elongated slits. In an exemplary embodiment, the wind turbine rotor blade includes a backing structure attached to the wind turbine rotor blade fairing, and the surface of the blade is configured to provide structural support for the wind turbine rotor blade fairing.

[0007] On the other hand, it relates to a wind turbine, comprising: a plurality of rotor blades, each of the plurality of rotor blades comprising: a span direction; a root portion; a shoulder; and a wind turbine rotor blade flow deflector, the wind turbine rotor blade flow deflector comprising: a first portion including a rear surface for facing the surface of the wind turbine rotor blade; and a second portion connected to the first portion and extending from the first portion along a length in a first direction, the second portion including a top surface angled at an angle between 90° and 180° relative to the rear surface of the first portion, wherein the second portion includes a plurality of corrugations extending along the length, wherein the second portion further includes a plurality of openings configured to allow flow to pass through the second portion, wherein the wind turbine rotor blade flow deflector is connected to the blade such that the rear surface of the first portion faces the surface of the blade, and wherein the wind turbine rotor blade flow deflector is connected to the wind turbine rotor blade between the root portion and the shoulder in the span direction.

[0008] The foregoing and other structural features and operations will be more readily understood and fully appreciated from the following detailed disclosure considered in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Some embodiments will be described in detail with reference to the following drawings, in which like reference numerals represent like components, wherein:

[0010] Figure 1 A perspective view of a wind turbine according to an embodiment of the present invention is depicted;

[0011] Figure 2 A perspective view of a wind turbine rotor blade provided with a plurality of flow deflectors according to an embodiment of the present invention is depicted;

[0012] Figure 3 Depicted is a cross-sectional view taken along arrow 3-3 of the wind turbine rotor blade shown in Figure 2 according to an embodiment of the present invention;

[0013] Figure 4 Depicted is a perspective view of one of the flow deflectors of Figure 2 according to an embodiment of the present invention;

[0014] Figure 5 Depicted is another exemplary flow deflector according to an embodiment of the present invention;

[0015] Figure 6 Depicted is another exemplary flow deflector according to an embodiment of the present invention; and

[0016] Figure 7 Depicted is a perspective view of the transition region of the wind turbine rotor blade of Figure 2 according to an embodiment of the present invention. Detailed Implementation Modes

[0017] Referring to the accompanying drawings, by way of example and not limitation, a detailed description of the following-described embodiments of the disclosed apparatus and method is presented herein. Although certain embodiments are shown and described in detail, it should be understood that various changes and modifications can be made without departing from the scope of the appended claims. The scope of the present disclosure will in no way be limited to the number of constituent parts, their materials, their shapes, their relative arrangements, etc., and is disclosed only as an example of the embodiments of the present disclosure.

[0018] As a prelude to the detailed description, it should be noted that, as used in this specification and the appended claims, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise.

[0019] Briefly, the present invention provides a flow deflector device for a wind turbine rotor blade, which can be attached to a wind turbine rotor blade, improving the aerodynamic characteristics of the wind turbine rotor blade. In addition, the present invention provides a wind turbine and a wind turbine rotor blade on which one or more flow deflector devices are mounted. The flow deflector device of the present invention can advantageously be attached to the trailing edge of the wind turbine rotor blade on the pressure side of the blade, so as to improve the energy capture characteristics of the wind turbine and its blade by improving the lift generated by the blade when attached to the intended position. Although the lift is improved, the flow deflector device of the present invention envisioned herein is further enhanced by a drag reduction feature. Specifically, the flow deflector device conceived herein includes an opening configured to allow flow to pass therethrough, thereby exciting the wake of the flow behind the blade and its flow deflector device, and thus reducing the size of the wake and resulting in a reduction in drag.

[0020] Now referring to the accompanying drawings, Figure 1 A perspective view of a wind turbine 1 according to an embodiment of the present invention is depicted. The wind turbine 1 includes a tower 2, a nacelle 3, and a hub 4. The nacelle 3 is located at the top of the tower 2. The hub 4 includes a plurality of wind turbine blades 5. The hub 4 is pivotally mounted such that the hub 4 is capable of rotating about a rotational axis 9. A generator may be located within the nacelle 3. The wind turbine 1 is a direct drive wind turbine. Although Figure 1 An exemplary wind turbine may be depicted, but the present invention is not limited to the shown configuration, and the flow deflector device described herein can be attached to any wind turbine rotor blade.

[0021] Figure 2 A perspective view of a wind turbine rotor blade 5 provided with a plurality of flow deflector devices 10 according to an embodiment of the present invention is depicted. Although the characteristics and dimensions of the wind turbine rotor blade 5 are shown as a blade that would typically be constructed for a three-blade rotor, the present invention is not limited to a three-blade rotor or the shown configuration. For example, the present invention can be implemented on a single-blade or two-blade rotor.

[0022] The rotor blade 5 is shown as including a root region 17 extending from a root 13. The root 13 includes a cylindrical profile. A transition region 16 extends from the root region to a shoulder 14. The shoulder 14 is defined as the location of its maximum profile depth, i.e., the maximum chord length of the blade 5. From the shoulder 14, the rotor blade 5 extends to a tip 12. The tip 12 forms the outermost part of the blade 5. The cylindrical profile of the root portion 13 is used to fix the blade 5 to a bearing of the rotor hub 4. Between the shoulder 14 and the tip 12, an airfoil portion 15 extends, which has a profile with an aerodynamic shape. In the transition region 16, a transition occurs from the aerodynamic profile of the airfoil portion 15 to the cylindrical profile of the root portion 13.

[0023] The span of the blade 5 is denoted by the reference numeral 11. The rotor blade flow deflector 10 of the present invention can be located at the rotor blade 5 in the span direction, between the root portion 13 and the shoulder 14. This means that the distance between the rotor blade flow deflector 10 and the root 13 in the span direction can be less than the distance between the shoulder 14 and the root 13 in the span direction.

[0024] As Figure 2 shown, a plurality of deflectors 10 are provided on the transition region 16 of the wind turbine rotor blade 5. Specifically, the rear surface of the deflector 10 can be attached or otherwise connected to the outer surface of the rotor blade 5 at the transition region 16. The attachment of the deflector 10 can be provided via an adhesive, bolts, welding, or any other form of attachment. Although a plurality of deflectors 10 are shown attached to the transition region 16 of the wind turbine 5, it is conceivable to attach one or more deflectors 10 at any position between the root 13 and the shoulder 14. Thus, it is conceivable to attach one or more deflectors 10 to the root region 17 and / or in place of the transition region 16. In addition, it is also conceivable that one or more deflectors 10 can extend beyond the root region 17 and / or the transition region 16 and extend into at least a part of the span 11 of the blade 5.

[0025] Figure 3 Depicted is a Figure 2 cross-sectional view of the wind turbine rotor blade 5 taken at arrow 3-3 according to an embodiment of the present invention. The rotor blade 5 is shown as a cross-section of the transition region 16. Figure 3The aerodynamic profile shown in the embodiment includes a pressure side 20 and a suction side 21, and a chord length 24 extending between a leading edge 22 and a trailing edge 23. The blade guide device 10 is shown as being located on the pressure side 20 of the aerodynamic profile close to the trailing edge 23. The blade guide device 10 may be located anywhere on the pressure side 20 of the aerodynamic profile. As shown, the blade guide device 10 is shown close to the trailing edge 23 without extending beyond the chord length 24 of the aerodynamic profile of the blade 5. The blade guide device 10 may also be closer to the trailing edge 23 than the illustrated embodiment, but still on the trailing edge half of the pressure side 20 of the blade 5.

[0026] Figure 4 Describes an embodiment of the present invention Figure 2 1 is a perspective view of one of the flow guiding devices 10 of FIG. The flow guiding device 10 includes a first portion 30 having a rear surface 31 for facing a surface of a wind turbine rotor blade. The flow guiding device 10 also includes a second portion 32 connected to the first portion 30 and extending from the first portion 30 in a first direction 33 along a length 34 of the second portion 32. The second portion 32 includes a top surface 35 angled at an angle 43 relative to the rear surface 31 of the first portion 30. The second portion 32 includes a plurality of corrugations 36 extending along the length 34. The second portion 32 also includes a plurality of openings 40 configured to allow flow to pass through the second portion 32. By allowing flow, such as air flow, to pass through the plurality of openings 40, the flow guiding device 10 can be configured to stimulate a wake of the flow behind the blade and its flow guiding device, and thereby reduce the size of the wake and result in a reduction in drag relative to a flow guiding device 10 having the same structure but without the openings 40. The openings 40 may not incur additional costs with respect to load while increasing efficiency. The transition portion 42 is disposed between the first portion 30 and the second portion 32, thereby defining a transition between the first portion 30 and the second portion 32. The transition portion 42 may be a curved portion of the flow guiding device 10. The plurality of corrugations 36 at least partially extend into the transition portion 42.

[0027] The plurality of openings 40 in the second portion 32 of the flow guide device 10 include a plurality of elongated slits extending perpendicularly to the first direction 33, each slit having an inverted V shape. In addition, the plurality of elongated slits are arranged in a plurality of rows. Specifically, the second portion 32 includes four openings 40 in each row. Each opening corresponds to a corrugated member 36, so that the apex of the inverted V shape is located within a channel or groove of the corrugated member 36. Three rows of openings 40 extend perpendicularly to the first direction 33. The top row of the openings 40 is shown close to the top surface 35 of the second portion 32. The middle row and the lower row of the openings 40 are arranged to be closer and closer to the transition portion 42. However, each even the lowermost row is shown to be closer to the top surface 35 than the transition portion 42. In the illustrated embodiment, equal spacing is provided between each of these rows.

[0028] Figure 5 FIG. 100 depicts another exemplary flow deflector 100 according to an embodiment of the present invention. Similar to the flow deflector 10, the flow deflector 100 includes a first portion 130 having a rear surface 131 for facing the surface of a wind turbine rotor blade. The flow deflector 100 further includes a second portion 132 that is connected to the first portion 130 and extends from the first portion 130 in a first direction 133 along the length 134 of the second portion 132. The second portion 132 includes a top surface 135 that is angled at an angle 143 relative to the rear surface 131 of the first portion 130. The second portion 132 includes a plurality of corrugations 136 that extend along the length 134. A transition portion 142 is disposed between the first portion 130 and the second portion 132, thereby defining a transition between the first portion 130 and the second portion 132. The transition portion 142 may be a curved portion of the flow deflector 100. The plurality of corrugations 136 extend at least partially into the transition portion 142. Similar to the plurality of openings 32 in the second portion of the flow deflector 10, the second portion 132 also includes a plurality of openings 140 configured to allow flow to pass through the second portion 132. By allowing flow, such as an air flow, to pass through the plurality of openings 140, the flow deflector 100 can be configured to energize the wake of the flow behind the blade and its flow deflector, and thereby reduce the size of the wake and result in a reduction in drag relative to a flow deflector 100 having the same structure but without the openings 140. The openings 140 do not create an additional cost with respect to the load while increasing the efficiency.

[0029] The plurality of openings 140 in the second portion 132 of the flow deflector 100 include a plurality of elongated slits that extend perpendicular to the first direction 133. Different from the plurality of openings 40 in the flow deflector 10, the plurality of openings 140 are shown as straight vertical slits without an inverted V shape. Similar to the plurality of openings 40 in the flow deflector 10, the plurality of elongated slits are arranged in multiple rows. Specifically, the second portion 132 includes four openings 140 in each row. Each opening corresponds to a corrugation 136. Three rows of openings 140 extend perpendicular to the first direction 133. The top row of the openings 140 is shown as being close to the top surface 135 of the second portion 132. The middle row and the bottom row of the openings 140 are arranged to be closer and closer to the transition portion 142. However, each even the lowest row is shown as being closer to the top surface 135 than the transition portion 142. In the illustrated embodiment, an equal spacing is provided between each row.

[0030] Figure 6Depicts another exemplary flow deflector 200 according to an embodiment of the present invention. Similar to the flow deflectors 10, 100, the flow deflector 200 includes a first portion 230 having a rear surface 231 for facing the surface of a wind turbine rotor blade. The flow deflector 200 further includes a second portion 232 that is connected to the first portion 230 and extends from the first portion 230 in a first direction 233 along the length 234 of the second portion 232. The second portion 232 includes a top surface 235 that is angled at an angle 243 relative to the rear surface 231 of the first portion 230. The second portion 232 includes a plurality of corrugations 236 that extend along the length 234. A transition portion 242 is disposed between the first portion 230 and the second portion 232, thereby defining a transition between the first portion 230 and the second portion 232. The transition portion 242 may be a curved portion of the flow deflector 210. The plurality of corrugations 236 extend at least partially into the transition portion 242. Similar to the second portions 32, 132 of the flow deflectors 10, 100, the second portion 232 further includes a plurality of openings 240 that are configured to allow flow to pass through the second portion 232. By allowing flow, such as an air flow, to pass through the plurality of openings 240, the flow deflector 200 can be configured to energize the wake of the flow behind the blade and its flow deflector, and thereby reduce the size of the wake and result in a reduction in drag relative to a flow deflector 200 having the same structure but without the openings 240. The openings 240 may not incur additional costs with respect to loads while improving efficiency.

[0031] The plurality of openings 240 in the second portion 232 of the flow deflector 100 include a plurality of elongated slits disposed across the width of the second portion 232. Different from the openings 40, 140 of the flow deflectors 10, 100, the plurality of openings 240 extend in a first direction 233 parallel to the side edges of the flow deflector 200. The vertically extending openings 240 correspond to the corrugations 234, where each individual opening 240 is located at the apex or ridge of each corrugation 234. Thus, there are five openings 240 that are disposed on the ridges of each of the five corrugations 234. Each opening 240 extends the same distance along the second portion 232 of the flow deflector 200.

[0032] Although each of the flow deflectors 10, 100, 200 shows various arrangements of the openings 40, 140, 240, it is to be understood that various other embodiments with more openings, fewer openings, differently shaped or sized openings, or differently arranged openings can be conceived. For example, it is conceivable to have more or fewer than three rows of vertically arranged openings. It is conceivable to have more or fewer than five vertically extending openings. In one embodiment, a plurality of circular openings may be provided in the second part of the flow deflector. Regardless of the embodiment, the goal of any opening arrangement can be to reduce drag by exciting the wake of the flow behind the blade and its flow deflector, and thus reduce the size of the wake, and result in a reduction in drag relative to the flow deflectors 10, 100, 200 having the same structure but without openings therein.

[0033] In each of the embodiments of the flow deflectors 10, 100, 200 described above, the first part 30, 130, 230 and the second part 32, 132, 232 can be made of a single piece or otherwise integrally formed. For example, the flow deflectors 10, 100, 200 can each be a corrugated and curved structure made of a single piece of metal or composite material. A plurality of corrugations 34, 134, 234 can extend parallel to the side edges of the flow deflector 10 in the direction 33, 133, 233. Although the rear surface 31, 131, 231 of the first part 30, 130, 230 can appear straight in each of the flow deflectors 10, 100, 200, the rear surface 31, 130, 230 can include a curvature corresponding to the surface of the wind turbine rotor blade to which the flow deflectors 10, 100, 200 are configured to be attached.

[0034] Although embodiments of the flow deflectors 10, 100, 200 in which the second part 32, 132, 232 and the first part 30, 130, 230 are angled relative to each other at any angle 43, 143, 243 between 90° and 180° can be conceived, a narrower range may be desirable. For example, the top surface 35, 135, 235 of the second part 32, 132, 232 can be arranged at an angle between 110° and 160° relative to the rear surface 31, 131, 231 of the first part 30, 130, 230.

[0035] Figure 7 Depicted in accordance with an embodiment of the present invention Figure 2Perspective view of the transition region 16 of the wind turbine rotor blade 5. The transition region 16 is shown between the root region 17 and the airfoil section 15 of the blade 5. The transition region 16 is shown to include sixteen flow deflectors 200 that are attached across the region 16 to the surface 50 of the blade 5. A backing structure 300 is attached to the wind turbine rotor blade flow deflector 200, and the surface 50 of the blade 5 is configured to provide structural support for the wind turbine rotor blade flow deflector 200. As with the sixteen flow deflectors 200, there may be sixteen separate backing structures 300. In the illustrated embodiment, both the backing structure 300 and the flow deflector 200 may be adhered to the surface 50 of the blade 5. The backing structure 300 may be short enough so as not to overlap the second portion 242 of the flow deflector 200 where the opening 240 is located. Alternatively, the opening 240 may extend through each of the flow deflector 200 and the backing structure 300. While this embodiment shows a single type of flow deflector 200 positioned across the entire span of the transition region 16, other embodiments may include different flow deflectors 200 attached at different locations along the span of the transition region 16. For example, it may be desirable to include a flow deflector having one type of opening at one end of the transition region, but a different type of opening at the opposite end of the transition region. Thus, it is contemplated to include different flow deflectors having different opening structures on the same rotor blade.

[0036] While it is contemplated that the flow deflectors have machined openings as shown in flow deflectors 10, 100, 200, other contemplated embodiments include using porous material for at least some of the second portions 32, 132, 232. The porous material may allow some flow to pass therethrough to achieve a drag reduction effect similar to that of the machined openings.

[0037] While the present disclosure has been described in connection with the specific embodiments outlined above, it will be apparent that many alternatives, modifications, and variations will be obvious to those skilled in the art. Accordingly, the preferred embodiments of the present disclosure as set forth above are intended to be illustrative and not restrictive. Various changes may be made without departing from the spirit and scope of the invention as claimed in the appended claims. The claims provide the scope of the invention and should not be limited to the specific examples provided herein.

Claims

1. A flow guiding device for a wind turbine rotor blade, comprising: A first part, which includes a rear surface for facing a surface of a wind turbine rotor blade; and A second part, which is connected to the first part and extends from the first part along a length in a first direction, the second part including a top surface angled at an angle between 90° and 180° relative to the rear surface of the first part; wherein the second part includes a plurality of corrugations extending along the length, and wherein the second part further includes a plurality of openings configured to allow flow to pass through the second part, wherein the flow deflector is configured to excite a wake of the blade and the flow behind the flow deflector by allowing flow to pass through the plurality of openings, and wherein the plurality of openings are arranged within the second part in a pattern corresponding to the plurality of corrugations, and wherein for each corrugation, there is a single opening or a row of openings.

2. The flow guiding device for a wind turbine rotor blade according to claim 1, wherein, The first part and the second part are made as a single piece.

3. The flow guiding device for a wind turbine rotor blade according to claim 2, wherein, A transition part is arranged between the first part and the second part, and wherein the plurality of corrugations extend into the transition part.

4. The flow guiding device for a wind turbine rotor blade according to claim 1, wherein, The top surface of the second part is arranged at an angle between 110° and 160° relative to the rear surface of the first part.

5. The flow guiding device for a wind turbine rotor blade according to claim 1, wherein, The plurality of openings include a plurality of elongated slits arranged across the width of the second part, the plurality of elongated slits extending in the first direction.

6. The flow guiding device for a wind turbine rotor blade according to claim 1, wherein, Each of the plurality of openings includes a plurality of elongated slits extending perpendicular to the first direction.

7. The flow guiding device for a wind turbine rotor blade according to claim 6, wherein, The plurality of openings include multiple rows of the elongated slits.

8. The flow guiding device for a wind turbine rotor blade according to claim 1, wherein, The plurality of openings include a plurality of elongated slits extending perpendicular to the first direction, each elongated slit having an inverted V shape.

9. The flow guiding device for a wind turbine rotor blade according to claim 8, wherein, The plurality of openings include multiple rows of the elongated slits.

10. A wind turbine rotor blade, comprising: Spanwise direction; Root part; Shoulder; and A wind turbine rotor blade flow deflector, comprising: A first part, which includes a rear surface for facing a surface of a wind turbine rotor blade; and A second part, which is connected to the first part and extends from the first part along a length in a first direction, the second part including a top surface angled at an angle between 90° and 180° relative to the rear surface of the first part; wherein the second part includes a plurality of corrugations extending along the length, and wherein the second part further includes a plurality of openings configured to allow flow to pass through the second part, and wherein the flow deflector is configured to excite a wake of the blade and the flow behind the flow deflector by allowing flow to pass through the plurality of openings, and wherein the plurality of openings are arranged within the second part in a pattern corresponding to the plurality of corrugations, and wherein for each corrugation, there is a single opening or a row of openings; wherein the wind turbine rotor blade flow deflector is connected to the blade such that the rear surface of the first part faces the surface of the blade, and wherein the wind turbine rotor blade flow deflector is connected to the wind turbine rotor blade between the root part and the shoulder in the spanwise direction.

11. The wind turbine rotor blade according to claim 10, wherein, The first and second portions of the wind turbine rotor blade fairing are made as a single piece.

12. The wind turbine rotor blade according to claim 11, wherein, A transition portion is disposed between the first and second portions of the wind turbine rotor blade fairing, and the plurality of corrugations extend into the transition portion.

13. The wind turbine rotor blade according to claim 10, wherein,The top surface of the second portion of the wind turbine rotor blade fairing is disposed at an angle between 110° and 160° relative to the rear surface of the first portion.

14. The wind turbine rotor blade according to claim 10, wherein, The plurality of openings of the wind turbine rotor blade fairing include a plurality of elongated slits disposed across the width of the second portion, the plurality of elongated slits extending in the first direction.

15. The wind turbine rotor blade according to claim 10, wherein, Each of the plurality of openings of the wind turbine rotor blade fairing includes a plurality of elongated slits extending perpendicular to the first direction.

16. The wind turbine rotor blade according to claim 15, wherein, The plurality of openings include multiple rows of elongated slits.

17. The wind turbine rotor blade according to claim 10, wherein, The plurality of openings of the wind turbine rotor blade fairing include a plurality of elongated slits extending perpendicular to the first direction, each elongated slit having an inverted V-shape.

18. The wind turbine rotor blade according to claim 17, wherein, The plurality of openings include multiple rows of the elongated slits.

19. The wind turbine rotor blade according to claim 10, further comprising a backing structure attached to the wind turbine rotor blade fairing, and the surface of the blade is configured to provide structural support for the wind turbine rotor blade fairing.

20. A wind turbine, comprising: A plurality of rotor blades, each of the plurality of rotor blades including: A spanwise direction; A root portion; A shoulder; and A wind turbine rotor blade fairing, comprising: A first portion including a rear surface for facing a surface of the wind turbine rotor blade; and A second portion connected to the first portion and extending in a first direction along a length from the first portion, the second portion including a top surface angled at an angle between 90° and 180° relative to the rear surface of the first portion, and wherein the fairing is configured to excite a wake of the blade and the flow behind the fairing by allowing flow to pass through the plurality of openings, and wherein the plurality of openings are provided in the second portion in an arrangement corresponding to the plurality of corrugations, and wherein for each corrugation there is a single opening or a row of openings; wherein the second portion includes a plurality of corrugations extending along the length, and wherein the second portion further includes a plurality of openings configured to allow flow to pass through the second portion, wherein the wind turbine rotor blade fairing is connected to the blade such that the rear surface of the first portion faces the surface of the blade, and wherein the wind turbine rotor blade fairing is connected to the wind turbine rotor blade between the root portion and the shoulder in the spanwise direction.

Images