# Acoustic Pulse

 Register Blogs Members List Search Today's Posts Mark Forums Read

 August 1, 2011, 11:47 Acoustic Pulse #1 Member   kostas Join Date: Jun 2010 Posts: 34 Rep Power: 8 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?

 August 2, 2011, 03:23 #2 Senior Member   cfdnewbie Join Date: Mar 2010 Posts: 557 Rep Power: 12 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..

 August 2, 2011, 05:30 #3 New Member   aaaaaaaaaaaaaa Join Date: Apr 2011 Posts: 23 Rep Power: 7 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?

August 2, 2011, 07:46
#4
Senior Member

andy
Join Date: May 2009
Posts: 129
Rep Power: 9
Quote:
 Originally Posted by pankos 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.

 August 2, 2011, 12:23 #5 Senior Member   cfdnewbie Join Date: Mar 2010 Posts: 557 Rep Power: 12 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....

 August 5, 2011, 14:19 wolfram alpha #6 New Member   phillip Join Date: Aug 2011 Posts: 7 Rep Power: 7 just ask wolframalpha.com to integrate it for you.

 Thread Tools Display Modes Linear Mode

 Posting Rules You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is OffTrackbacks are On Pingbacks are On Refbacks are On Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post Nico FLUENT 1 October 11, 2012 02:35 Matthew Roberts FLUENT 2 June 2, 2011 13:11 Gavisiddayya FLUENT 0 October 8, 2007 11:24 Hugh FLUENT 0 October 1, 2006 21:54 larry Main CFD Forum 8 July 19, 2002 03:40

All times are GMT -4. The time now is 13:10.