[LAD] Audio Levitation

[Dominique Michel]

Le Sat, 4 Jan 2014 13:39:05 +0000,
Fons Adriaensen <fons at linuxaudio.org> a écrit :

> On Sat, Jan 04, 2014 at 09:24:54PM +1100, Patrick Shirkey wrote:
> 
> > Does cavitation have a role to play?
> 
> No idea. If it does that could be rather destructive on some
> materials.
> 
> What is clear is that acoustic radiation pressure plays a role.
> And that's a subject that has caused a lot of confusion and false
> results throughout the history of acoustics as a science. Some big
> names (including Rayleigh) have burnt their fingers on it, so it's
> not and easy matter. To prime the confusion, there are at least 
> two formulations of acoustic radiation pressure: one from Rayleigh
> (which depends on non-linearity) and one due to Langevin (which
> does not depend on it).

According to that presentation
http://www.dalembert.upmc.fr/Oleron2010/docs/Presentations/Oleron-Barriere.pdf
it look like Langevin (which is the same than Rayleigh first formula
in 1902) apply well when we are long enough from the source, and when
we are in its vicinity, Rayleigh (1905) must be applied.

Dominique

> 
> Ciao,
>