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Old   August 1, 2011, 11:47
Default Acoustic Pulse
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kostas
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I want to validate a Euler equations solver using the acoustic pulse as test case.
However, the exact solution of it, is complex to derived due to the appearence of integral which involves a bessel function.

What can i do for derive the exact solution? Any suggestions?
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Old   August 2, 2011, 03:23
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would it have to be an acoustic pulse? you may start with sth simpler and build up from there to validate the code...e.g. the standard test case: pulse in rho..
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Old   August 2, 2011, 05:30
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Could you tell me more information for this case? Some papers which setup the test?

The convection of isentropic vortex is not good problem for validation?
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Old   August 2, 2011, 07:46
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Quote:
Originally Posted by pankos View Post
I want to validate a Euler equations solver using the acoustic pulse as test case.
However, the exact solution of it, is complex to derived due to the appearence of integral which involves a bessel function.

What can i do for derive the exact solution? Any suggestions?
Integrate the Bessel function using one of the many tricks you learnt at school and university? If your recall is a bit wonky then googling "integrate Bessel function" is likely to provide a whole bunch of options.
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Old   August 2, 2011, 12:23
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Start by using a density pulse with a velocity field (should be convected along the streamlines).
If that works, use the method of the manufactured solution to create sth like a sinewave solution and test convergence with that - if you actually have access to the code and can add a source term, that is....
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Old   August 5, 2011, 14:19
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just ask wolframalpha.com to integrate it for you.
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