Chord extenders for a wind turbine rotor blade assembly

1. A rotor blade assembly for a wind turbine, the rotor blade assembly comprising:

a rotor blade extending lengthwise between a root and a tip, the rotor blade including a pressure side and a suction side extending between a leading edge and a trailing edge; and

a chord extender including an attachment portion coupled to at least one of the pressure side or the suction side and an extension portion extending outwardly from the attachment portion beyond the trailing edge, the extension portion extending in a spanwise direction of the rotor blade between an inboard end and an outboard end opposite the inboard end, the extension portion extending in a chordwise direction of the rotor blade between a first end disposed adjacent to the trailing edge and a second end disposed opposite the first end, the second end of the extension portion being spaced apart from the trailing edge and defining a straight outer edge of the extension portion extending from the inboard end to the outboard end of the extension portion, the extension portion including a surface defined between the first and second ends and the inboard and outboard ends, the extension portion further including at least one stiffening rib projecting outwardly from the surface.

2. The rotor blade assembly of claim 1 , wherein the at least one stiffening rib extends lengthwise along the surface of the extension portion between a first rib end and a second rib end, the first rib end being disposed directly adjacent to the trailing edge.

3. The rotor blade assembly of claim 2 , wherein, when an aerodynamic load is applied against the extension portion that causes the extension portion to pivot relative to the trailing edge, an end face of the first rib end engages against the trailing edge of the rotor blade.

4. The rotor blade assembly of claim 2 , wherein the surface corresponds to an upper surface of the extension portion, the upper surface facing in the substantially same direction as the suction side of the rotor blade.

5. The rotor blade assembly of claim 2 , wherein the at least one rib projects outwardly to a height above the surface, the height being tapered as the at least one rib extends lengthwise along the surface between the first and second rib ends in the direction of the second end of the extension portion.

6. The rotor blade assembly of claim 2 , wherein a maximum height of the at least one rib is defined at the first rib end.

7. The rotor blade assembly of claim 1 , wherein a spanwise width of the at least one rib is greater than a chordwise length of the at least one rib.

8. The rotor blade assembly of claim 1 , wherein a spanwise width of the at least one rib is less than a chordwise length of the at least one rib.

9. The rotor blade assembly of claim 1 , further comprising a plurality of ribs projecting outwardly from the surface, the plurality of ribs being spaced apart from another along a spanwise length of the extension portion.

10. The rotor blade assembly of claim 1 , wherein the attachment portion comprises a first attachment section coupled to the pressure side of the rotor blade and a second attachment section coupled to the suction side of the rotor blade, the first and second attachment sections intersecting at the first end of the extension portion.

11. The rotor blade assembly of claim 1 , wherein the extension portion defines a straight profile or a curved profile between the first and second ends.

12. The rotor blade assembly of claim 11 , wherein the curved profile corresponds to a concave profile or a convex profile.

13. The rotor blade assembly of claim 1 , wherein the extension portion defines a chordwise length between the first and second ends, the chordwise length ranging from about 5% to about 20% of a local chord of the rotor blade defined at the chord extender.

14. The rotor blade assembly of claim 1 , wherein the extension portion is oriented at an angle relative to a chord line of the rotor blade ranging from about 5 degrees to about 30 degrees.

15. A chord extender for a rotor blade of a wind turbine, the rotor blade including a pressure side and a suction side extending between a leading edge and a trailing edge, the chord extender comprising:

an attachment portion configured to be coupled to an outer surface defined by at least one of the pressure side or the suction side of the rotor blade;

an extension portion configured to extend outwardly from the attachment portion beyond the trailing edge of the rotor blade, the extension portion extending in a spanwise direction of the rotor blade between an inboard end and an outboard end opposite the inboard end, the extension portion extending in a chordwise direction between a first end configured to be disposed adjacent to the trailing edge and a second end disposed opposite the first end, the second end of the extension portion being spaced apart from the trailing edge and defining a straight outer edge of the extension portion extending from the inboard end to the outboard end of the extension portion, the extension portion including a surface defined between the first and second ends and the inboard and outboard ends; and

at least one stiffening rib projecting outwardly from the surface of the extension portion, the at least one stiffening rib extending lengthwise along the surface between a first rib end and a second rib end, the first rib end being configured to be disposed adjacent to the first end of the extension portion.

16. The chord extender of claim 15 , wherein the surface corresponds to an upper surface of the extension portion, the upper surface facing in the substantially same direction as the suction side of the rotor blade.

17. The chord extender of claim 15 , wherein the at least one rib projects outwardly to a height above the surface, the height being tapered as the at least one rib extends lengthwise along the surface between the first and second rib ends in the direction of the second end of the extension portion.

18. The chord extender of claim 15 , wherein the extension portion defines a straight profile or a curved profile between the first and second ends.

19. The chord extended of claim 15 , wherein the straight outer edge defined by the second end of the extension portion extends generally parallel to the trailing edge of the rotor blade from the inboard end to the outboard end of the extension portion.

20. The rotor blade assembly of claim 1 , wherein the straight outer edge defined by the second end of the extension portion extends generally parallel to the trailing edge of the rotor blade from the inboard end to the outboard end of the extension portion.