Experimental results of the Sound absorption coefficient of material have mostly been found to be in good terms with the Theoretical models. But the calculations look confusing. With imaginary terms and differential equations.
Are there any simplified calculations and methods for theoretical modeling in acoustics?
Abhishek, the short answer is yes.
The long answer is that the simplified calculation depends on the type of absorber and, to some extent, on the application. There are essentially three types of absorbers: porous, Helmholtz and membrane. Manufacturers of rockwool and acoustic grade fibreglass batts publish absorption curves which remove the need for any calculation. Likewise with acoustic ceiling tiles. There are also online calculators for Helmholtz absorbers and membrane absorbers.
Translating these into room acoustic behaviour is a little more complicated, as rooms are three dimensional, while simplified absorption models are one dimensional. Again though, there are software programs such as Odeon and Catt Acoustic that allow room acoustic behaviour to be predicted with reasonable confidence without resorting to boundary element modelling or other finite element techniques.
If you are looking for simplified explanations and design techniques, The Master Handbook of Acoustics by F. Alton Everest is a good place to start.
Dear Ian Dash Thank you for your detailed explanation.
I will have a look at the article that you have mentioned.
I was going through the modeling of acoustics proposed by Maa. Which accounts for the SAC values as per Micro Perforations.
Thanks for your time and Suggestion.
Ian Dash I understand, Apologies for the confusion.
Thanks for the update and the article.
Article Investigation on micro-perforated panel absorber with ultra-...
https://docplayer.net/203728477-Designing-of-micro-perforated-panels-for-low-frequency-passive-acoustic-absorption.html
I was referring few articles and there were some changes in mathematical equations that are applied which makes me wonder which will be the accurate tool.
Regarding your question on the Nocke paper, Equation 6 is derived from the previous 5 equations. The numerical value of Equation 6 depends on the values chosen for the parameters b, d, t and D. If the system is linear, the impedance should not be dependent on sound pressure, so I am guessing that the p in the denominator should not be there.
- Badges
- Science topic