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Bernoulli UFO

...rolling in his grave.
(+1, -1)
  [vote for,

By using the same Bernoulli effect which suspends a sphere in a stream of air it should be possible to levitate a saucer shape as well.
Unfortunately a disk has the tendency to tilt and then fall out of the air stream as the pressure differential is negated.

I can't help wonder if small tilted louvers on the underside of the disk would cause the air flow to spin the disk and thus keep it from tilting by gyroscopic effect.

If the underside of the disk was flat, (other than louvers) and the top was rounded, the lessening of air pressure on the upper surface of the disk should cause it to hover.

Coanda effect http://jnaudin.free.fr/html/repcotst.htm
[2 fries shy of a happy meal, Jun 03 2008]

YouTube: Coanda Effect Flying Model http://www.youtube....watch?v=eAWVt13K2bM
[FlyingToaster, Jun 03 2008]

Italian UFO http://video.google...1912688412&q=&hl=en
most strange [xenzag, Jun 03 2008]


       pretty sure it's baked... similar to "Coanda Effect"
FlyingToaster, Jun 03 2008

       1) Viktor Schauberger's Repulsine.   

       2) And in cases where the object is not a sphere it is referred to as the Coanda effect. Using the tendancy of a jet stream to "stick" to a convex wall, creating a low pressure above a mass, by shaping the mass. "Usage" of this effect baked by Avro Canada. Success debatable, depending on which side of conspiracy theory you stand.
4whom, Jun 03 2008

       mostly you'd want to stand not underneath it. I don't think it got past "tethered flight" stage but it certainly is a "flying saucer".
FlyingToaster, Jun 03 2008

       I looked up Coanda effect, [link], thank you.   

       The difference between that and this idea is the direction of airflow.
For the Coanda effect to work the air must blow straight down on the curved surface. I believe that a Bernoulli version should work with airflow from the side and, unlike a sphere, be able to remain in the airflow even if that flow is completely horizontal.

       <shrugs> Just an hypothesis.   

       [2fries] so you envision a "hamster wheel" blower in the middle blowing air horizontally across top and bottom (and for a little extra lift, fed from the top) ? or a frisbee with couter-rotating middle, which tosses out boundary-layer air through centrifugal force...ahh both(?)
FlyingToaster, Jun 03 2008

       // I believe that a Bernoulli version should work with airflow from the side and, unlike a sphere, be able to remain in the airflow even if that flow is completely horizontal.// It is now commonly called a wing. The key to lift is an increased airflow accross the section. This can happen at increased wind velocity or increased wing velocity (the same thing really). If we take this wing and move it, say in a disk, on the plane we have invented the Helicopter. Very much an anti-gravity device but it does need a stator. Critics of Viktor Schauberger will say his device is a glorified helicopter, and they would be right, IMHO. At some point in your device, something has to remain stationary. This could be the wind source, but then you cannot travel from this wind source (like bernoulli's ball). If you want to be independant of wind source then some part of your mechanism must remain (relatively) stationary.   

       I don't think you are talking about an intake at the centre of "helicopter" or "rotor" arms and blowing "wind" across the arms. Basically the downforce from the intake will negate lift from the rotors. I think you are talking about a helicopter with the stator in the middle, or in reverse as you have worded it. I think in theory it will work, but it requires a small volume, high power motor/engine.
4whom, Jun 03 2008

       Ah sorry, I can see that my wording was misleading.   

       The toy UFO is not a self contained flying device, merely a shape that I think will remain as stable as a sphere would in an airflow and would be nothing more than a desktop novelty.   

       This idea would work, perhaps even without rotating. If the jet of air is coming from the side, the top of the saucer is all that need be smooth and lifty. Make a domed top, put a bit of weight as low as possible, and Bob's your alien.   

       But the air needs to be going up a bit, say 45 degrees, or the saucer will just drift away. A completely horizontal airflow wouldn't be good.   

       That Italian "UFO" is amusing. It's dark underneath, even though it's supposedly flying over a reflective river.
baconbrain, Jun 03 2008

       Go forth and do it.
quantum_flux, Jun 03 2008


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