Arrangement to reduce noise originated by a wind turbine blade

Abstract

An arrangement for reducing noise which is generated by a wind turbine blade is provided. The wind turbine blade has a first panel and a second panel. The first and the second panel are arranged at a trailing edge of the wind turbine blade, wherein the first panel is adjacent to the second panel. The first panel includes a first transition zone and the second panel includes a second transition zone. The first transition zone and the second transition zone are engaged in a way that whistle tones produced by a gap of the wind turbine blade, the gap being located between the first panel and the second panel, is reduced or even avoided.

Claims

1. An arrangement to reduce noise, which is originated by a wind turbine blade, wherein the wind turbine blade comprises a first panel and a second panel, wherein the first panel and the second panel are arranged at a trailing edge of the wind turbine blade, wherein the first panel is adjacent to the second panel, wherein the first panel comprises a first transition zone, wherein the second panel comprises a second transition zone, wherein the first transition zone comprises only a first lip extending from a first panel main body and the second transition zone comprises only a second lip extending from a second panel main body; wherein only the first lip and the second lip overlap and are configured to allow flexible movement between the first panel and the second panel, wherein the first transition zone and the second transition zone are engaged such that whistle tones produced by a gap, which is located between the first panel and the second panel, are reduced or eliminated.

2. The arrangement according to claim 1, wherein the first lip and the second lip are shiplapped.

3. The arrangement according to claim 1, wherein the first and second panels are arranged and prepared for a flexible movement of the panels.

4. The Arrangement according to claim 3, wherein engaged first and second transition zones are prepared to support the flexible movement of the panels.

5. The arrangement according to claim 3, wherein the first and second panels are arranged and shaped such that aerodynamic characteristics of the blade are improved.

6. The arrangement according to claim 1, wherein the first and second panels each comprise a plurality of serrations which are arranged and shaped such that aerodynamic characteristics of the wind turbine blade are improved.

7. The arrangement according to claim 1, wherein the first and second panels are connected to the trailing edge via a glued connection.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a blade with panels as starting point for the arrangement.

(2) FIG. 2 shows the engagement of the panels according to an embodiment.

(3) FIG. 3 shows a detail of the connection, which is shown in FIG. 2.

(4) FIG. 4 to FIG. 7 show a known blade of a wind turbine as described previously.

DETAILED DESCRIPTION OF INVENTION

(5) FIG. 1 shows a blade 11 with panels 21. A plurality of panels 21 are arranged at and along the trailing edge TE1 of the blade 11. The panels 21 show a number of serrations SE1.

(6) The size and the shape of the panels 21 are optimized in a way that a lift-drag-ratio of the blade 11 is increased. Thus the aerodynamic characteristics of the blade 11 are improved.

(7) The panels 21 might be connected by glue with the trailing edge TE1. Thus retrofitting of existing blades 11 in dependency of specific conditions of the site of the wind turbine is quite easy.

(8) The panels 21 may be made in smaller sections and may be attached side by side as illustrated. Thus an entire flap, arranged at the trailing edge TE1 of the blade 11, is established or constituted.

(9) FIG. 2 shows the engagement of the panels 21 according to an embodiment. Reference is made to FIG. 1 and to the circle shown there. The panels 21 are arranged in adjacent manner as shown in FIG. 1.

(10) A first panel 21A comprises a first transition zone TZ1. A second panel 21B comprises a second transition zone TZ2. The first transition zone TZ1 and the second transition zone TZ2 each comprises a lip. The lips overlap each other, thus, the lips are engaged when the panels 21 are positioned at the trailing edge TE1 of the blade 11.

(11) The gap GP1, which is arranged between the panels 21A and 21B, is reduced in its dimension; thus, the origination of whistle tones by the gap GP1 is reduced or even avoided.

(12) The overlap allows the flexible movement of the panels 21 in relation to each other. Thus the flexibility of the construction is maintained.

(13) FIG. 3 shows the engaged lips LIP and the engaged transition zones TZ1, TZ2 with reference to FIG. 2 and FIG. 1.

(14) While specific embodiments have been described in detail, those with ordinary skill in the art will appreciate that various modifications and alternative to those details could be developed in light of the overall teachings of the disclosure. For example, elements described in association with different embodiments may be combined. Accordingly, the particular arrangements disclosed are meant to be illustrative only and should not be construed as limiting the scope of the claims or disclosure, which are to be given the full breadth of the appended claims, and any and all equivalents thereof. It should be noted that the term comprising does not exclude other elements or steps and the use of articles a or an does not exclude a plurality.