Hydrophone measurements in conjunction with time-controlled high-speed imaging of the claw closure demonstrate that the sound is emitted at the cavitation bubble collapse and not on claw closure. A model for the bubble dynamics based on a Rayleigh-Plesset-type equation quantitatively accounts for the time dependence of the bubble radius and for the emitted sound.
Sonoluminescence is a phenomena observed when bubbles of noble gases are driven by ultrasonic waves.
Nevertheless, there are some useful predictions here and good prospects for getting some really hot plasmas inside bubbles. So, is bubble fusion back on the table? If this model proves to be accurate, and experimentalists can find a suitably clean system to work with, then yes, it might well be. Will bubble fusion ever be a replacement for the likes of ITER? No. New Journal of Physics, 2009,
Cavitation is essentially a dynamic condition in a liquid system that forms a vapor or gas-filled hole or "cavity" in the liquid. It can be caused by several different mechanisms, but in engine cooling systems it is most often a result of cylinder liner vibration caused by piston slap and/or combustion pressures.
Here is what Archimedes would like to have said: One - Since every body loses weight in proportion to the degree to which it is displaced by a specifically densifying medium (see note 14)... then, Two - Sit in bath = loose weight (displacement of water). Three - Sit on floor = loose no weight (no displacement of medium). Four - If medium surrounding is more dense then it determines motion. Five - Schauberger's trout (see note 15) expulses a densified fluid about its rear, as it expands it squeezes the trout forward. Six - If you create a situation where normal air is more dense than the air directly above or ahead of the craft - the normal air will move the craft ! Seven - There are two sorts of 'levitational motive force' featured in the many machines of Viktor Schauberger... Eight - One, a spinning upwards force would provide a NEGATIVE (vacuous) air density above the craft. Two, if the craft utilised only the centrifugal force, as in a Repulsine, it would propel a POSITIVE (increased) air density below the craft. Both these motive forces will send the craft up into the air.
Originally posted by sapien82
NO BOX , no annoying sound , this guy had it down !
Yes leviation using sound wave resonance , the hutchinson effect , not sure if this is the same thing but this guy had been doing it since the 70's i believe
Originally posted by Phage
reply to post by LucidDreamer85
If the standing wave is being created by reflection off of a wall the nodes will be horizontally distributed. Acoustical levitation requires that the nodes be vertically distributed, the object gets "caught" between nodes.
In order to be levitated, the object has to be smaller than the wavelength of the sound. To give you a rough idea, to levitate a basketball a frequency of 400Hz would have to be used. That's about a middle G note. No problem there but the amount of energy required would be huge. It takes 154 dB (a jet engine 100 feet away produces 140 dB) to levitate a water drop 1.4mm in diameter (about .15 gram) that basketball weighs 567 grams, 3,780 times as much. I don't think it can be done. I don't think there is a sound loud enough.
Reflecting sound waves does not amplify the energy. If you are talking about audio feedback, that requires an electronic amplifier.
[edit on 1/21/2010 by Phage]