Methods for manufacturing flatback airfoils for wind turbine rotor blades

1. A method for manufacturing a wind turbine rotor blade having a flatback airfoil configuration along at least a portion of a span of the rotor blade, the method comprising:

providing a shell mold of the rotor blade;

laying up an outer skin layer of the rotor blade into the shell mold;

placing at least one pre-fabricated corner of the flatback airfoil configuration into the shell mold, the at least one pre-fabricated corner having a pointed edge; and,

infusing the outer skin layer with the at least one pre-fabricated corner to form the flatback airfoil configuration.

2. The method of claim 1 , further comprising forming the at least one pre-fabricated corner via additive manufacturing.

3. The method of claim 2 , wherein the at least one pre-fabricated corner is constructed of a thermoplastic material.

4. The method of claim 1 , wherein the at least one pre-fabricated corner comprises at least one of a downwind corner of the flatback airfoil configuration or an upwind corner of the flatback airfoil configuration.

5. The method of claim 1 , further comprising placing the at least one pre-fabricated corner of the flatback airfoil configuration into the shell mold exterior to the outer skin layer.

6. The method of claim 5 , further comprising coating the at least one pre-fabricated corner of the flatback airfoil configuration with a coating material.

7. The method of claim 1 , further comprising placing one or more additional skin layers exterior to the at least one pre-fabricated corner.

8. The method of claim 7 , further comprising providing a break in the one or more additional skin layers that aligns with the pointed edge of the at least one pre-fabricated corner to maintain pointedness of the pointed edge.

9. The method of claim 7 , wherein the at least one pre-fabricated corner comprises an exterior surface having a predetermined roughness to help the one or more additional layers adhere thereto.

10. The method of claim 7 , wherein the one or more additional skin layers comprises a thermoplastic material reinforced with one or more fiber materials, wherein the one or more fiber materials comprise at least one of glass fibers, carbon fibers, polymer fibers, wood fibers, bamboo fibers, ceramic fibers, nanofibers, metal fibers, or combinations thereof.

11. The method of claim 1 , further comprising forming the at least one pre-fabricated corner via an ultra-sound signal transmitting material such that the flatback airfoil configuration can be inspected via non-destructive testing (NDT) inspection.

12. The method of claim 1 , wherein the shell mold comprises first and second shell mold halves, the step of laying up the outer skin layer of the rotor blade into the shell mold further comprises:

laying up a first side of the outer skin layer in the first shell mold half; and,

laying up a second side of the outer skin layer in the second shell mold half.

13. The method of claim 12 , further comprising:

placing the at least one pre-fabricated corner into one of the first side or the second side of the outer skin layer; and,

joining the first and second sides of the outer skin layer together at first and second joints.

14. A rotor blade, comprising:

exterior surfaces comprising a pressure side, a suction side, a leading edge and a trailing edge each extending in a generally span-wise direction between an inboard region and an outboard region,

wherein the trailing edge comprises a flatback airfoil configuration in the inboard region, the flatback airfoil configuration comprising at least one pre-fabricated corner co-infused with the exterior surfaces, the at least one pre-fabricated corner formed using a thermoplastic material, the at least one pre-fabricated corner having a pointed edge.

15. The rotor blade of claim 14 , wherein the at least one pre-fabricated corner comprises at least one of a downwind corner of the flatback airfoil configuration or an upwind corner of the flatback airfoil configuration.

16. The rotor blade of claim 14 , wherein the at least one pre-fabricated corner of the flatback airfoil configuration is exterior to the exterior surfaces of the rotor blade.

17. The rotor blade of claim 14 , further comprising one or more additional skin layers exterior to the at least one pre-fabricated corner.

18. The rotor blade of claim 17 , further comprising a break in the one or more additional skin layers that aligns with the pointed edge of the at least one pre-fabricated corner to maintain pointedness of the pointed edge, wherein the one or more additional skin layers comprises a thermoplastic material reinforced with one or more fiber materials.

19. A method for manufacturing a flatback airfoil, the method comprising:

providing a shell mold of the airfoil;

laying up an outer skin layer of the airfoil into the shell mold;

forming at least one corner of the flatback airfoil via additive manufacturing, the at least one corner defining a pointed edge of the airfoil; and,

securing the at least one corner exterior to the outer skin layer to form the flatback airfoil.

20. The method of claim 19 , wherein securing the at least one corner exterior to the outer skin layer to form the flatback airfoil further comprises at least one of bonding or melting the at least one corner to an exterior surface of the outer skin layer.