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Dyson windmill

Bladeless
 
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The dyson fans are nifty. I suspect that they have a vigorously rotating inner ring but am not sure; there does not seem to be any guard for inserted fingers.

I wonder if a breeze entering such a fan would generate electricity. It seems to me it must. Any motor turned by an extrinsic force becomes a generator and this should be no different.

A bladeless windmill of this sort would present no threat to birds and arguably might be at less risk for damage from extreme weather than is the case for conventional big-bladed windmills.

bungston, Nov 29 2010

Dyson fans http://www.dyson.com/store/fans.asp
I think the inner ring rotates. But I am not sure. [bungston, Nov 29 2010]

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       The technology is not readily invertable. If I remeber correctly, there is a normal fan in the base. This produces air that is blown out the ring, entraining air as it passes through the ring, producing a greater total volume. (along with a couple of other effects) None of this works in reverse.
MechE, Nov 29 2010
  

       As [MechE] said, it isn't reversible. There's a rapidly-turning centrifugal impeller in the base, that feeds high-pressure air up into the ring, and a little slot all around the ring that the high-pressure air shoots out of, aiming into the ring. That drags other air through the ring with it, and that drags air from around the fan with it, which makes a lot of slower-moving air to fan your face. All from a snarly little high pressure "fan".   

       Trying to run that backward would be like sticking a shower nozzle out in the rain and expecting to fill your water tower.   

       You might be able to set up a giant Dyson fan ring in the wind, and use it to suck air out of a tube, like a venturi, but that isn't an exact reversal and might not be efficient use of the wind area.   

       There are some propellors with rapidly-rotating inner rings, by the way. One is used on a submersible vehicle.
baconbrain, Nov 29 2010
  

       Dang! Thanks for the anno's. I never got around to looking up how the fan worked. I was hoping it was something more than what it is, I reckon.
Zimmy, Dec 11 2010
  

       Perhaps a big funnel with a small turbine at the back could work? The dyson method appears to be a complicated way of folding the funnel and hiding the fan.   

       I want one, mostly to throw paper aeroplanes through.
saedi, Dec 12 2010
  
      
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