Does Turbulence Keep Wind Turbines In Phase?

[Rev. Green]

Yesterday, two wind turbines kept in phase for all the time that I watched them. Was turbulence locking their rotations together? One was directly downwind of the other. A third turbine, at the side of the others, did not keep in phase. All turbines were similar and would be expected to turn at about the same rate. Also, they might have reached a limiting speed because the wind was strong. However, there should have been some change of phase over the period of twenty to thirty minutes for which they were observed.

[Atheist]

RevGreen; I'm afraid I can't help you with your question, but I've got one for you. I love the sight of Eoliennes (Fr) in the countryside, but some say that they are noisy and I've only seen them when I drive past so I've never heard or seen them close up. Did you notice the noise that they made?

[Rev. Green]

Sorry, Atheist. I walked a large loop and never came close enough to hear the turbines. Here's a personal question: I'm not a real Rev., I'm a Cluedo character, Prof Plum was already in use, but are you a real Atheist?

[jno]

maybe one just needed oiling (or some other minor technical adjustment to stop it falling behind)?

[Peter Pedant]

read this
https://www.witpress.com/Secure/elibrary/papers/9781845642051/9781845642051001FU1.pdf

and you will never ask another question about a wind turbine

turbulence - no: makes it more inefficient

it is relatively easy to see that if two machines are coincidentally identical ( that is the variations just dont make a difference) then they will rotate at the same speed ( angular vel, w)
but that doesnt explain why they tip at 12 o'clock at the same time and were "locked in" ( like the earth and sunny side of the moon)

[Togo]

THere are a number of reasons why they may turn at different speeds. On land one that is higher, say on a hill, may turn faster due to wind speed being higher. Also the units have an automatic braking system that inhibits or attenuates the rotation if it is too windy(no kidding) they may even shut down fully to prevent damage by overheating the bearings. Also the blades can be feathered remotely from a control unit,just like an oar in water. If demand is low it may be dilligent to reduce the output of some of the windmills because electricity storage is difficult. The speed of rotation, and therefor the output, can be reduced by feathering the blades, to make them less efficient, to not making full use of the wind. It can be done individually for each unit.

[Togo]

We have hundreds off the coast in view here, and I looked at this very thing some years ago after wondering why some were not turning and why some were slower. Weird effect at night when the red lights are making random patterns.

[Peter Pedant]

oh,
they all are
synchronous, fixed speed

https://en.wikipedia.org/wiki/Variable_speed_wind_turbine

so the only issue is why the 12 o'clocks lined up
I go for chance....

[Togo]

Sometimes there is another strange effect where the turbines that are in the wake of others as the wind passes, turn slower because the wind is being dissapated by the ones that get the breeze first. When there is a large bank of them in rows and columns they sometimes turn slightly faster in the wind first rows than the wind last rows. That is also very strange to gaze at. I know ... but I do. :))

[Atheist]

Rev Green. I'm a bit like Richard Dawkins. On a scale of 1 to 10 (1 is someone who 'knows' that there is a god, and 10 is someone who 'knows' that there is not a god) then I am a 9. I see no need for a god: I think that the word god is simply a word which means 'a description of all the things we don't yet know but need a word to camouflage our current ignorance'.
Making up a word seems to be a way of avoiding our search for answers.

[Peter Pedant]

Hmm - - so you are not gonna pray for divine guidance on this one.

That is also very strange to gaze at. I know ... but I do. :))
50 y ago we used to stare at the bacon-slicer

[Atheist]

The windmills obey the eternal and unerring will of Eolius! End of!

[Peter Pedant]

oh, them
Aeolian harps - they what go ning-a-ning-a-ning in the wind
are stretched strings and have a intrinsic frequency
and
along comes the wind....( constant )
but around the stretched string there is vortex shedding

https://en.wikipedia.org/wiki/Vortex_shedding

yes reader you read right Karman vortex shedding and this means the force is variable BUT regular and twangs the right string.

Karman vortex shedding ( cue old grumpy !) is meant to be the basis of that wibbly wobbly bridge at Tacoma coming down in 1940

see You tube