Wind power: for or against the wind?

[sicetaitsimple]

Complement: moreover by magnifying the photo, it seems to me to distinguish very well on the mast on the ground the different sections and, above the type on the right, the trace of the first weld.

[lilian07]

I think it is at the first weld section that the mast has broken (we can distinguish the section elements on the mast on the ground).
In addition, it is at this level that the efforts are most important.
The axial thrust of a wind turbine when it turns can be interpreted as a giant disc "stopping" half of the force of the wind. If the wind turbine is 1 MW its energy harvest is around 200W per m2 swept (nominal wind speed) by the 40m blades, so a harvesting surface of 5000 m2 at 50m high, we imagine the pushed up ....
With such a lever arm, at the base of the mast we find immense efforts, a significant gust of wind faster than the feathering can destroy the mast without fatigue and sever it more or less clearly.

[Ahmed]

Yes, Sicetaitsimple, I confused with the sub-assemblies which are indeed longer, but each section does not appear as a single block, since it is itself composed of several welded plates ...
The cutout does not follow the junction faithfully, however, as far as one can judge from this single view, but if it does, the welder has failed in his task.

Lilian07, you write:

With such a lever arm, at the base of the mast there are immense forces, a significant gust of wind faster than feathering can destroy the mast without fatigue and sever it more or less clearly.

I totally agree with the strong leverage effect, but in other cases the downed wind turbines bent and here a fatigue phenomenon, perhaps associated with a faulty weld, is quite plausible .

[Christophe]

One thing is certain: foundations have nothing

[sicetaitsimple]

The cutout does not follow the junction faithfully, however, as far as one can judge from this single view, but if it does, the welder has failed in his task.
[

You may be going a bit fast in terms of diagnosis, based on a photo.

I think that there will be no problem, for specialists, on the basis of the fracture facies and the current characteristics of the steel, to determine what happened, at the level of the weld or not.

Remember that this wind turbine (based on the initial article) is 15 years old. So, problem with feathering, weld defect, fatigue sizing? Me, I do not know.

[Gaston]

With such a lever arm, at the base of the mast we find immense efforts, a significant gust of wind faster than the feathering can destroy the mast without fatigue and sever it more or less clearly.

According to the operator, all the wind turbines in this field had been feathered preventively several hours before the fall.
This does not prevent the existence of considerable efforts, but still much less strong than if the wind turbine had been in production.

[lilian07]

So if it was at a standstill it's astonishing .... bad soldering probable? mini tornado? but really astonishing it is really an accident which should not happen often.

[Remundo]

I think the wind cracked the weld on the stretching side, the mast when falling finished cracking the part which was in compression (which bent).

I don't know if we will get feedback from the experts ... not sure.

[chatelot16]

the wind really has incomprehensible whims ... we can make it as solid as possible, there is always something that loose in one place, and yet was not the most fragile ... but it's whirlwinds weird that multiply the effort on the thing that nature wants to break ... nature is stronger than us

I do not see the collapse of this mast as a disaster: I rather see it as a success that there is only one mast fallen! despite the large number of wind turbines built for a long time

there is no large wind turbine near a house or a road ... so in a strong wind there is no chance that someone will pass under ... so a wind turbine that falls with a wind exceptional it's really not that inadmissible

[Ahmed]

Sicetaitsimple, you write:

You may be going a bit fast in terms of diagnosis, based on a photo.

This "diagnosis" is very conditional, since I took care to be as less affirmative as possible:

as far as one can judge from this single sight

et

but si it is indeed the case, it is that the welder failed in his task