Academic Question on Aeroacoustics
Academic Question on Aeroacoustics
(OP)
Hello Again,
I would like to know if someone has any idea of how to predict the sound pressure level for a case where sound is being emmited from three rectangular slits at the end of a long tunnel like a ventilation duct. The slits are very small compared to the dimensions of the tunnel and are placed at approximately the centre line of the tunnels end face. The slits open into atmosphere.The tunnel has a fluid flow, most commonly air at a certain speed which causes the noise at the slits.
What theory/equations could be best used? Can the the slits be modelled as Quadrupole sources?
I would be really thankful if anyone sends pdfs or links on similar measurements to correlate the model that i am trying to build.
Thanks in advance.
I would like to know if someone has any idea of how to predict the sound pressure level for a case where sound is being emmited from three rectangular slits at the end of a long tunnel like a ventilation duct. The slits are very small compared to the dimensions of the tunnel and are placed at approximately the centre line of the tunnels end face. The slits open into atmosphere.The tunnel has a fluid flow, most commonly air at a certain speed which causes the noise at the slits.
What theory/equations could be best used? Can the the slits be modelled as Quadrupole sources?
I would be really thankful if anyone sends pdfs or links on similar measurements to correlate the model that i am trying to build.
Thanks in advance.





RE: Academic Question on Aeroacoustics
state what you are dealing with, pressures, flow (or velocity), current noise levels, etc
RE: Academic Question on Aeroacoustics
Now the question is, given the velocity of the air in the duct and the duct and grill cross section areas, how does one calculate the SPL/SWL coming out of the grill?
Any help will be GREATLY appreciated :)
Thanks in advance.
RE: Academic Question on Aeroacoustics
Once you know the sound power spectrum at the grill the attenuation in the duct/room is easy to estimate, any textbook for architectural acoustics will have appropriate equations.
I strongly recommend you read a general acoustics book such as Beranek.
Cheers
Greg Locock
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RE: Academic Question on Aeroacoustics
Yes i have already looked into Beranek but it didnt help as much i had expected it to.
Thanks a lot for the reply again.
RE: Academic Question on Aeroacoustics
Doesn't that come perilously close to circular logic?