## Visualisation of Wave Acoustics

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### Visualisation of Wave Acoustics

Hi All,

As some of you may know I'm now working on my doctorate which has quite a lot of elements in acoustics modelling.
I'm employing a numerical method to solve the wave equation in the time domain, so discrete time-space values of pressure or particle velocity come naturally with the solution.
(more details upon request).

As it turns out, this is not only a good way to calculate IRs of rooms, but also for visualising sound propagation.

So I thought it would be nice to take some basic wave behavior and acoustic phenomena, and be able to show how they occur.

Since these things weigh a ton, I threw everything in a u-toob channel:

(wanted to embed something here for an example, but no idea how to do this)

Cheers,

Jon.
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jonessy

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### Re: Visualisation of Wave Acoustics

Nice!.
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bert stoltenborg

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### Re: Visualisation of Wave Acoustics

Hey Jon,

Your a math canon, is sound pressure in phase with voice coil (or membrane) speed or with voice coil acceleration?
If you view life with the knowledge that there are no problems, only opportunities, you are a marketing manager.......this is my personal philosophy
bert stoltenborg

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### Re: Visualisation of Wave Acoustics

Marvelous. Thank you Jon.

Andre
avare

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### Re: Visualisation of Wave Acoustics

Cheers guys.

Bert -

If I understand your question correctly, then no.

The source term is a pressure source which is obtained by considering a volume velocity source; delayed and filtered, hence out of phase.
(this is an outcome of discretising the source function in a way that it satisfies its respective PDE).

What you see in the animations (even at the source location) is the change of acoustic pressure, caused by the aforementioned source.

Hope this answers the question (and if I misunderstood - then please tell).

Cheers,

Jon.
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jonessy

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### Re: Visualisation of Wave Acoustics

Wow, nice work Jon!

Did you try to model some stationary waves ? I'm not sure how hard is it to make all the boundaries rigid/reflective, but it would be interesting to see how the waves become stationary after one/few cycles.

PS : regarding the youtube videos embedding, Dan might have disabled this when he upgraded the forum (same as it is with the user avatars, except those didn't work before either).
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J.F.Oros

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### Re: Visualisation of Wave Acoustics

You mean 'standing waves'?
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jonessy

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### Re: Visualisation of Wave Acoustics

Oh yeah, standing waves of course

Sorry, I was kind of tired when i wrote that (coming from a long trip) and used the romanian version of the word (we say "stationary waves" here, on a direct translation)
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J.F.Oros

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### Re: Visualisation of Wave Acoustics

Jonathan, thanks, really nice.
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