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 The information provided may be out of date.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.

Acoustic materials - integrate in the

Jean-Philippe Regnard
Hi,
i have a problem with the material library.
I make some acoustic simulations with absorbing materials. There is the possibility to use the Delany & Bazley model in the acoustic module but in the theory of acoustic materials there is others models more accurate than this.
I compute on matlab the celerity and density (complex number) corresponding to the materials which are record in a text file. Of course, the density and celerity are frequency dependent.
Is it possible in comsol to read the text file with the data to use them in the simulation?
Thank for your answer.
Jean-Philippe

1 Reply Last Post Oct 11, 2012, 9:52 AM EDT
COMSOL Moderator

Hello Jean-Philippe Regnard

Your Discussion has gone 30 days without a reply. If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for help.

If you do not hold an on-subscription license, you may find an answer in another Discussion or in the Knowledge Base.

Davide Borelli
Posted: 5 years ago Oct 11, 2012, 9:52 AM EDT
Hi,
the Miki model has been added in the newer versions of the software.
Anyway, from the documentation, I can understand that the Miki model is the one which simply modifies the Delany Bazley coefficients (Miki Y., Acoustical properties of porous materials - Modifications of Delany-Bazley models, J. Acoust. Soc. Jpn (E). 11(1), 1990, pp. 19-24), often called the "D-B-Miki model", and not the one described in Miki Y., Acoustical properties of porous materials - Generalizations of empirical models, J. Acoust. Soc. Jpn (E). 11(1), 1990, pp. 25-28, usually called the "Miki model".
It would be nice and more clear if the actual "Miki" model would be renamed "Delany-Bazley-Miki", and it would also be nice if more modern modifications of the model, like the Komatsu one (T. Komatsu. 2008. Improvement of the Delany-Bazley and Miki models for fibrous sound-absorbing materials. Acoust. Sci. & Tech., 29(2), 121-129, perso.ensait.fr/vromanp/documents/publications/Komatsu-2007.pdf) would be added.



Hi,
i have a problem with the material library.
I make some acoustic simulations with absorbing materials. There is the possibility to use the Delany & Bazley model in the acoustic module but in the theory of acoustic materials there is others models more accurate than this.
I compute on matlab the celerity and density (complex number) corresponding to the materials which are record in a text file. Of course, the density and celerity are frequency dependent.
Is it possible in comsol to read the text file with the data to use them in the simulation?
Thank for your answer.
Jean-Philippe


Hi, the Miki model has been added in the newer versions of the software. Anyway, from the documentation, I can understand that the Miki model is the one which simply modifies the Delany Bazley coefficients (Miki Y., Acoustical properties of porous materials - Modifications of Delany-Bazley models, J. Acoust. Soc. Jpn (E). 11(1), 1990, pp. 19-24), often called the "D-B-Miki model", and not the one described in Miki Y., Acoustical properties of porous materials - Generalizations of empirical models, J. Acoust. Soc. Jpn (E). 11(1), 1990, pp. 25-28, usually called the "Miki model". It would be nice and more clear if the actual "Miki" model would be renamed "Delany-Bazley-Miki", and it would also be nice if more modern modifications of the model, like the Komatsu one (T. Komatsu. 2008. Improvement of the Delany-Bazley and Miki models for fibrous sound-absorbing materials. Acoust. Sci. & Tech., 29(2), 121-129, http://perso.ensait.fr/vromanp/documents/publications/Komatsu-2007.pdf) would be added. [QUOTE] Hi, i have a problem with the material library. I make some acoustic simulations with absorbing materials. There is the possibility to use the Delany & Bazley model in the acoustic module but in the theory of acoustic materials there is others models more accurate than this. I compute on matlab the celerity and density (complex number) corresponding to the materials which are record in a text file. Of course, the density and celerity are frequency dependent. Is it possible in comsol to read the text file with the data to use them in the simulation? Thank for your answer. Jean-Philippe [/QUOTE]

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.