Menu

Discussion Forum

New Discussion
Filtrer

Note: This discussion is about an older version of the COMSOL Multiphysics® software. The information provided may be out of date.

Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

effect of pml thickness and meshing in acoustics-structural module

Posted 1 mars 2015, 14:45 UTC−5 Acoustics & Vibrations, Mesh, Parameters, Variables, & Functions Version 4.4 4 Replies

Sandesh Gopinath
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Hi everyone,
I am trying to simulate the frequency response of a thin membrane using acoustic-structural interaction module.The issue is with meshing of all domains and the pml thickness levels.
For my model,changing mesh from normal to fine changes the frequency response drastically.And also just increasing the pml thickness from 5mm to 10 mm also changes the response a lot.
I am checking the response by measuring the sound pressure level between 1-16 khz at a point at the beginning of the pml layer.
Can any one advise me on these issues,or are these things expected to be the way they are.
Thanks for the help,
Sandesh

Attachments:

4 Replies Last Post 2 mars 2015, 17:13 UTC−5
Sergei Yushanov Certified Consultant
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 10 years ago 2 mars 2015, 09:39 UTC−5
Sandesh,

There are certain requirements on mesh for wave-type problems:
-place 5-6 elements thought the thickness of PML
-use Swept mesh for PML domains
-resolve wavelength (at least 6 second order elements per wavelength)

None of the above is fulfilled in your model. Attached is modified file which shows that pressure distribution is independent on thickness of PML.

Regards,
Sergei
Sandesh, There are certain requirements on mesh for wave-type problems: -place 5-6 elements thought the thickness of PML -use Swept mesh for PML domains -resolve wavelength (at least 6 second order elements per wavelength) None of the above is fulfilled in your model. Attached is modified file which shows that pressure distribution is independent on thickness of PML. Regards, Sergei
Sandesh Gopinath
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 10 years ago 2 mars 2015, 14:20 UTC−5
Thank you sergei.
Can you please attach the modified file.
Thank you sergei. Can you please attach the modified file.
Sergei Yushanov Certified Consultant
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 10 years ago 2 mars 2015, 14:30 UTC−5
Sandesh,

Attached is modified file.

Regards,
Sergei
Sandesh, Attached is modified file. Regards, Sergei

Attachments:

Sandesh Gopinath
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 10 years ago 2 mars 2015, 17:13 UTC−5
Thank you Sergie.The model works like a charm.
I actually want to sweep through frequencies,so would the mesh adapt itself for every frequency automatically or do i have to make some changes?
Thank you Sergie.The model works like a charm. I actually want to sweep through frequencies,so would the mesh adapt itself for every frequency automatically or do i have to make some changes?

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.

Suggested Content