Girder for supporting a tidal turbine fairing and tidal turbine comprising such a girder

1. A girder for supporting a fairing of a tidal turbine, the girder comprising:

a parallelogram-shaped cross-section, taken perpendicularly to a longitudinal axis of the girder; and

at least one slot extending generally parallel with the longitudinal axis of the girder,

in a cross-section taken perpendicularly to the longitudinal axis of the girder, traces of surfaces bordering the slot extend from one of long sides of the cross-section to an adjacent short side of the cross-section.

2. The girder according to claim 1 , wherein the short side of the cross-section forms an acute angle with the adjacent long side of the cross-section.

3. The girder according to claim 1 , wherein, in a perpendicular plane to the longitudinal axis of the girder, an angle, situated outside the girder, on the side of a joining edge between the short side of the cross-section and the long side of the cross-section with respect to the slot, and defined between a portion of the long side, situated on the side of the edge with respect to the slot, and a median or mean axis of the slot, is greater than 90 degree.

4. The girder according to claim 3 , wherein, in a perpendicular plane to the longitudinal axis of the girder, the angle, situated outside the girder is greater than 120°.

5. The girder according to claim 3 , wherein, in a perpendicular plane to the longitudinal axis of the girder, the angle, situated outside the girder is between 130° and 160°.

6. The girder according to claim 3 , wherein, in a perpendicular plane to the longitudinal axis of the girder, the angle, situated outside the girder is in the region of 150°.

7. The girder according to claim 1 , wherein, in a perpendicular plane to the longitudinal girder axis, an angle, situated inside the girder, and defined by a long side of the parallelogram and by a short side of the parallelogram forming an obtuse angle with the long side, is greater than 90°.

8. The girder according to claim 1 , wherein at least two slots extend from the same long side of the parallelogram.

9. The girder according to claim 8 , wherein the slots extending from the same long side of the parallelogram are parallel.

10. The girder according to claim 1 , wherein at least one slot extends from each long side.

11. The girder according to claim 1 , wherein the girder is equipped with fixing means for assembling two parts of the girder situated on either side of the same slot.

12. The girder according to claim 1 , wherein at least one part of the girder, situated on the side of a joining edge between the short side of the cross-section and the long side of the cross-section with respect to the slot, is made of a material having a greater mechanical strength than that of the material forming a part of the girder situated opposite the edge with respect to the slot.

13. A tidal turbine comprising a rotatable wheel about an axis, a fixed fairing encasing the wheel and at least one girder for supporting the fairing connecting the fairing to a central water turbine supporting member, wherein the girder is according to claim 1 .

14. The girder according to claim 1 , wherein, in a perpendicular plane to the longitudinal girder axis, an angle, situated inside the girder, and defined by a long side of the parallelogram and by a short side of the parallelogram forming an obtuse angle with the long side greater than 120°.

15. The girder according to claim 1 , wherein, in a perpendicular plane to the longitudinal girder axis, an angle, situated inside the girder, and defined by a long side of the parallelogram and by a short side of the parallelogram forming an obtuse angle with the long side, is in the region of 150°.