Mounting Rotor on Chimney stack.

[Marco]

I remember being to ld not to mount a wind rotor on a chimney stack (mine will be 8ft dia.

The chimney presents a much greater surface area to the wind will adding the blades add any appreciable forces?

All I can think of is excessive vibration, but if my mounting pole is rigid enough, the re will be very little vibration.

Can someone please correct my thinking as I think I am missing something.

Marco

 

[hiker]

had my 19.5'cb. antenna mounted to my cement block chimney--had it up their for years..

then we had a big wind-80-90 mph..antenna was doing fine--that is untill the morter craked between the joints and down came the chimney and ant.the swaying back and forth in the wind cracked the morter joints..................

[Ungrounded Lightning Rod]

Vibration will cause repeated stresses that will break the chimney apart if it is masonry.  Other types aren't really all that strong, either.

A stiff mount will just be more effective at transferring the vibration to whatever it's fastened to.

Vibration is not good for the building structure, either.

And it's not good for your peace of mind or health to have your house turned into a sounding board.

Wind machines should be stand-alone for this reason.  Even guy wires should go to their own anchors and clear the house.

They should also be a significant distance away, if possible, for several reasons:

 - They'll do significant damage if they fall on the house.

 - They'll do extreme damage, and perhaps major personal injury, if they throw a blade and it hits the house.

 - They throw vorticese downwind which will also vibrate the house and create noise inside. (That includes subsonic noise, which causes stress though it's inaudible and is virtually impossible to screen out.)

 - Their efficiency is reduced by the turbulence and air slowing from the air's passage around the house or other nearby obstacles - especially when the wind is coming from the direction of the house, but to some extent even if it's going in other directions,

[finnsawyer]

There will always be vibration.  Sound is vibration.  Mortar and brick are not elastic like steel.  Don't do it.

[nothing to lose]

Like everyone says, don't do it.

I have seen old and not so old masonary chimney just loosen up and let the top bricks/blocks fall free for no real reason. Imagine what would have came loose if an antenna had been installed on them.

Course there was a reason they fell apart, but antenna stress was not it. Faulty materials/workmanship on the newer ones, just old age and weather stresses perhaps on the older ones.

[kenputer]

We have a small gennie mounted to the cable end of our cottage. I used rubber bumpers to cut down on vibartions and it seems to work fine.

[inode buddha]

Well, I have a 35-foot chimney of red brick, and the wind in the winter turns it into a giant whistle. I would be afraid to put anything on it unless it ran the full height of it, and then it would be noisy anyhow. I asked a friend of mine who deals insurance, and he says that doing something like that would probably void the policy.

[ignesandros]

Would an old telephone pole work form mounting a genny?

-Andrew