June 21, 2010: Flaming Fans
 

Someone emailed me a whole bunch of pictures of burning wind turbines.
At first thought was lightning strikes, but the more I thought about it, I would think they would be built to handle that. After all, they stick way up in the air, out in the open. But snooping around the web, it seems to be the gear box oil, from malfunctioning drivetrains, catching fire.

http://cellar.org/2010/burningturbinesop.jpg

I didn't find any frequency of failure statistics, but seeing what can happen when they do fail makes me wonder. Is it safe to be plonking these things down in flammable forests and grasslands, out in the middle of nowhere?:unsure:

Not to worry, FEMA will clean up the oil spills.

Awesome! The birds are hitting back!

That looks like it is going to be expensive to repair.

LOL! It's funny because they exist to use cleaner energy.

I think I posted this before - or someone else did.
At least this one didn't catch fire. Dunno where those blades flew off to though :eek

I read something about them having difficulty with high winds. They have brake systems which overheat or something??? Maybe its the gearboxes to which Bruce is referring.

found this one also . . .

I thought this thread was going to be about the audience at a Bette Midler show.

Haggis!

About a month ago I saw one of these turbines en route to who-knows-where. The things can be huge. The three turbine blades/props stopped at a local truck stop, I went back and waited around for a little while, I thought the hub might be travelling with the props, no such luck.

Safe?! Lets ask the folks on the Gulf Coast right now if they would rather deal with one of these things catching on fire and falling over, or the huge mess they currently have.

Sorry, I apologize for my momentary trip to the soap box.

Holy crap Grav! that thing is much bigger than I imagined.

lol - No problem.

Ugly turban accidents
 

The horror!!!

The first film looks like it was hit by an artillary shell. The windmills I studied in the eighties had a feathering mechanism that kicked in if the RPMs got too high.

Or it could be this ...

Link

ETA - Bruce was right , again.

I think that the turbines in post #7 are both older, and fairly small. A modern wind turbine rotates at 10 to 20 RPM, and those in the videos look like they're going quite a bit faster.

Of course, they're also on fire.

A buddy of mine photographed the construction of the blades. You can stand up inside them when they are laying down.

looks like the blade flexed and bashed into the tower.

The top right and bottom left turbines are, I think, the same as in post 7 & IIRC the bottom left in post 1 is the same exact turbine.

As for the rest I've no clue how old who made or anything else. From what limited reading I did today, the problem remains the same under abnormally high winds that are sustained for a length of time. The brakes/gearboxes overheat and fail.

probably Chinese made gearboxes...

How frigging hard can it be to make a gearbox that doesn't blow up? I think even GM can do that.

The gear boxes on the big turbines are like nothing else. I used to work for one of the labs that did fatigue testing on them and they were having a lot of trouble finding test equipment that was stronger than the gear boxes.

Regarding the blades striking the tower, part of the problem is that most of the turbines currently being manufactured are upwind turbines. When the wind blows it flexes the blades toward the tower. Downwind turbines don't have that problem, but they do have what's called "tower shadow." Every time the blades pass behind the tower they enter an area where the wind is blocked by the tower. This causes a cyclic loading on the blades, which contributes to fatigue failure and an increase in noise.

So is it that the lubricant failed? Now,another question, rather than trying to apply brakes, why not have the gears disengage when speeds or temps increase too greatly? The blades would go into a free spin until the temp cooled or the wind died down. And they would feather automatically to reduce their speed.

Why wouldn't that work?

They would probably have to make the blades more complex, and heavier, to allow them to overclock like that. :confused:

I guess fans are more complex than I thought. How did the Dutch handle this stuff for all these years?

There's are small, slow, and steerable. I believe their blades are framework skeletons, which are covered with canvas, like a sail, as needed.

At high enough rotational speeds the blades would self destruct.

Some control systems on smaller machines turn the turbine perpendicular to the wind when wind speeds get too high.

Great Capture!
I had no idea they were that big. they dont look that large from down on the ground. i drive past a few occasionally on the way to the airport. will drive a little faster past now.

The tail, like the ones on these 1904 St Louis World's Fair display, keep the blades pointed into the wind, like a weathervane. By folding the tail 90 degrees, it effectively shuts down the fan, either manually or as HLJ mentioned, as an automatic safety.

http://cellar.org/2010/windmills.jpg

Intersting. A study of the physics in making them work must have been fantastic.

I'm guessing around 100-120 feet, if ya figger that a regular trailer would be around fifty feet...

The usual size for a trailer is currently 53 feet end to end and it weighs 16,000 lbs empty.

The cost to replace a windmill is around one million per.

I see these things all the time.

Plus $3.99, shipping and handling.

I have four in three different internet shopping carts right now.

Should I get shipping insurance?

Use a Post Office's priority mail box and you don't have to weigh them.

Given the pictures in the op, this seems a little negligent.


http://keetsa.com/blog/wp-content/up...energy_179.jpg

There's something funny about that picture.

Looks like something to warn trucks of the clearance on the signs ahead.