Stress relief flange and method for distributing stress for wind turbine components

1. A flange for securing an upper tower section and a lower tower section of a wind turbine, the flange comprising:

a first arm extending in a first direction;

a second arm extending in a second direction, the second direction being substantially perpendicular to the first direction; and

a relief region disposed adjacent to the junction of the first arm and the second arm, the relief region including a space located below the surface of the junction of the first arm and the second arm.

2. The flange of claim 1 , wherein the relief region includes a predetermined size in relation to a height of the flange.

3. The flange of claim 2 , wherein the flange includes a predetermined amount of material between the relief region and a second flange.

4. The flange of claim 3 , wherein the predetermined amount of material between the relief region and the second flange is at least 35% of the height of the flange.

5. The flange of claim 2 , wherein the flange includes a predetermined amount of material between the relief region and a hole in the flange.

6. The flange of claim 5 , wherein the predetermined amount of material between the relief region and the hole in the flange is at least 10% of the height of the flange.

7. The flange of claim 1 , wherein the relief region includes a predetermined position in relation to a height of the flange.

8. The flange of claim 1 , wherein the relief region maintains or improves the distribution of stress on wind turbine components compared to a flange devoid of the relief region.

9. The flange of claim 8 , wherein the wind turbine components are selected from the group consisting of the first arm of the flange, the second arm of the flange, a fastener of the flange, and combinations thereof.

10. The flange of claim 9 , wherein the distribution of stress on the first arm is improved by at least 9% compared to a flange devoid of the relief region.

11. The flange of claim 9 , wherein the distribution of stress on the second arm is improved by at least 3% compared to a flange devoid of the relief region.

12. The flange of claim 9 , further comprising a fastener, wherein the distribution of stress on the fastener is improved by at least 1% compared to a flange devoid of the relief region.

13. A wind turbine, comprising:

at least one blade operably mounted on a tower, the at least one blade attached to a rotor having a rotor shaft, the rotor shaft in rotational communication with a generator, the tower including an upper tower section and a lower tower section;

a first flange, the first flange comprising:

a first arm extending in a first direction;

a second arm extending in a second direction, the second direction being substantially perpendicular to the first direction;

a relief region disposed adjacent to the junction of the first arm and the second arm, the relief region including a space located below the surface of the junction of the first arm and the second arm;

a second flange, the second flange comprising:

a first arm extending in a first direction;

a second arm extending in a second direction, the second direction being substantially perpendicular to the first direction;

a relief region disposed adjacent to the junction of the first arm and the second arm, the relief region including a space located below the surface of the junction of the first arm and the second arm;

and wherein the first flange is secured to the second flange.

14. The wind turbine of claim 13 , wherein the flange includes a predetermined amount of material between the relief region of the first flange and the relief region of the second flange.

15. The wind turbine of claim 13 , wherein the relief region maintains or improves the distribution of stress on wind turbine components compared to a flange devoid of the relief region.

16. A method of distributing stress in flanges securing an upper tower section and a lower tower section of a wind turbine, the method comprising: forming a first flange, the first flange comprising:

a first arm extending in a first direction;

a second arm extending in a second direction, the second direction being substantially perpendicular to the first direction;

a relief region disposed adjacent to the junction of the first arm and the second arm, the relief region including a space located below the surface of the junction of the first arm and the second arm;

forming a second flange, the second flange comprising:

a first arm extending in a first direction;

a second arm extending in a second direction, the second direction being substantially perpendicular to the first direction;

a relief region disposed adjacent to the junction of the first arm and the second arm, the relief region including a space, the space including a fillet below the surface of the junction of the first arm and the second arm; and

securing the first flange to the second flange with a fastener.

17. The method of claim 16 , further comprising maintaining or improving the distribution of stress on wind turbine components compared to a flange devoid of the relief region.

18. The method of claim 17 , wherein the distribution of stress on the first arm of the first flange is improved by at least 9% compared to a flange devoid of the relief region.

19. The method of claim 17 , wherein the distribution of stress on the second arm of the first flange is improved by at least 3% compared to a flange devoid of the relief region.

20. The method of claim 17 , further comprising a fastener, wherein the distribution of stress on the fastener is improved by at least 1% compared to a flange devoid of the relief region.