Investigating the Effect of Shape on Acoustic Performance of Micro Perforated Absorber at Low Frequencies

  • Mohammad Reza Monazzam School of Public Health and Center for Air Pollution Research (CAPR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran
  • Zahra Hashemi Mail Behbahan Faculty of Medical Sciences, Behbahan, Iran
Micro Perforated Absorbers, surface shapes, Low Frequency, Absorption Coefficient


Nowadays, micro-perforated absorbers are one of the structures that are widely used nowadays. The sound absorption mechanism is performed by viscous energy losses in the cavities on the plate. This paper examined the effect of the surface shape on the micro perforated absorber performance at low frequencies (less than 500 Hz). The three-dimensional finite element method was used to predict the absorption coefficient of this group of adsorbents. Also, the results obtained from the shaped absorbers were compared with the flat micro perforated absorbers. After validating the numerical results, six different designs were defined as the surface shape of the micro perforated plates in the COMSOL Multiphysics, Ver. 5.3a software. The results reflected the fact that the factor of the surface shape can be used as a contributing factor in some frequencies. In general, the dented or concave shapes provide better outcomes than other flat designs and shapes and the convex or outward shapes bring the weakest results.


1. Cox TJ, D' Antonio P.Acoustic Absorbers and Diffusers: Theory, Design and Application. Spon Press.London and New York.2005
2. Nelson DI, Nelson RY, Concha-Barrientos M, Fingerhut M. The global burden of occupational noise-induced hearing loss. Am J Ind Med. 2005; 48:446-58.DOI:10.1002/ajim.20223
3. Picard M, Girard SA, Simard M, Larocque R, Leroux T, Turcotte F. Association of work-related accidents with noise exposure in the workplace and noise-induced hearing loss based on the experience of some 240000person-years of observation. Accid Anal Prev.2008; 40: 1644-1652. doi: 10.1016/j.aap.2008.05.013
4. Ni CH, Chen ZY, Zhou Y, Zhou JW, Pan JJ, Liu N, Wang J, Liang CK, Zhang ZZ, Zhang YJ. Associations of blood pressure and arterial compliance with occupational noise exposure in female workers of textile mill. Chinese Med J.2007; 120: 1309-1313. DOI: 10.1097/00029330-200708010-00003
5. Niemann H, Bonnefoy X, Braubach M, Hecht K, Maschke C, Rodrigues C, Röbbel N. Noise-induced annoyance and morbidity results from the pan/European LARES Study. Noise Health. 2006; 8:9-32. DOI: 10.4103/1463-1741.33537
6. Dalton DS, Cruickshanks KJ, Klein BE, Klein R, Wiley TL, Nondahl DM. The impact of hearing loss on quality of life in older adults. Gerontologist.2003; 43: 661 – 668. doi: 10.2147/CIA.S26059
7. Kramer SE, Kapteyn TS, Kuik DJ, Deeg DJ. The association of hearing impairment and chronic diseases with psychosocial health status in older age.J Aging Health.2002; 14:122-137.
8. Babisch W. Transportation noise and cardiovascular risk: updated review and synthesis of epidemiological studies indicate that the evidence has increased. Noise and Health.2006; 8:1-24. DOI: 10.4103/1463-1741.32464
9. Berglund B, Hassmén P, Job RF. Sources and effects of low‐frequency noise. J Acoust Soc Am.1996; 5:2985-3002. DOI: 10.1121/1.414863
10. Persson Waye K, Bengtsson J, Kjellberg A, Benton S. Low frequency noise" pollution" interferes with performance. Noise and Health. 2001;4:33-49
11. Smith MG, Croy I, Ogren M, Persson Waye K. On the influence of freight trains on humans: a laboratory investigation of the impact of nocturnal low frequency vibration and noise on sleep and heart rate. PLoS One. 2013; 8:e55829. doi: 10.1371/journal.pone.0055829
12. Fuchs, H.V.; Zha, X. Micro-perforated structures as sound absorbers – a review and outlook. Acta Acust united Ac. 2006; 92:139–146.
13. Fuchs, H.V.; Zha, X. Acrylic-glass sound absorbers in the plenum of the deutscher bundestag. Appl Acoust.1992; 51:211-217.
14. Gemin Li, Chris K Mechefske. A comprehensive experimental study of micro-perforated panel acoustic absorbers in MRI scanners. Magn Reson Mater Phy. 2010; 23:177-185. DOI: 10.1007/s10334-010-0216-9
15. Wu M Q.Micro-perforated panels for duct silencing, NOISE CONTROL ENG J. 1997; 45:69-77. DOI: 10.3397/1.2828428
16. Allam s, Abom m, A new type of muffler based on micro perforated tubes, J. Vib. Acoust. 2011;133; doi:10.1115/1.4002956
17. Heidi R V, Pedro C, Finn J. Optimization of multiple-layer micro perforated panels by simulated annealing. Annual report year. Appl Acoust.2011;72:772-776

18. Wang C, Huang L, Zhang Y. Oblique incidence sound absorption of parallel arrangement of multiple micro-perforated panel absorbers in a periodic pattern. J Sound Vib.2014; 333:6828-6842.
19. Maa D Y. micro perforated-panel wide band absorbers, NOISE CONTROL ENG J. 1987; 29:77-84. DOI: 10.3397/1.2827694
20. Lee D H, Kwon Y P. Estimation of the absorption performance of multiple layer perforated panel systems by transfer matrix method, J Sound Vib. 2004; 278:847-860.
21. Bravo T, Maury C, Pinhède C.Enhancing sound absorption and transmission through flexible multi-layer micro-perforated structures, J Acoust Soc Am. 2013; 134:3663-3673. doi: 10.1121/1.4821215.
22. Hashemi Z, Monazzam M R, Fahim A. Estimation of Sound Absorption Performance of Complex Perforated Panel Absorbers by Numerical Finite Element Method and examining the role of Different Layouts behind It. FLUCT NOISE LETT .2019; DOI: 10.1142/S0219477519500135
23. Lee Y Y, Lee E W M, Ng C. F. Sound absorption of a finite flexible micro-perforated panel backed by an air cavity, J Sound Vib . 2005; 287: 227-243. DOI: 10.1016/j.jsv.2004.11.024
24. Chang D, Liu B, Li X. An electro mechanical low frequency panel sound absorber. J Acoust Soc Am.2010; 128:639-645. doi: 10.1121/1.3459838.
25. Chen W H, Lee F C, Chiang D M. On the acoustic absorption of porous materials with different surface shapes and perforated plates. J Sound Vib .2000; 237:337-355.
26. Easwaran V, Munjal M L Finite element analysis of wedges used in anechoic chambers. J Sound Vib .1993; 160:333-350.
27. Kang Y J, Bolton J S. Finite element modeling for sound transmission through foam-lined double-panel structures. J Acoust Soc Am. 1996; 99:27555-2765. DOI: 10.1121/1.414856
28. Tsay H S. Analysis of normal incidence absorption of pyramidal polyurethane foam by three-dimensional finite element frequency domain acoustical analysis. . J Acoust Soc Am.2006; 120:2686. DOI: 10.1121/1.2354044
29. Maa DY. Potential of micro perforated panel absorber, J Acoust Soc Am. 1998; 104:2861-2866.
30. Keller J B, Givoli D. Exactnon-reflecting boundary conditions. J Comput Phys.1989; 82:172-192.
31. Lee Y Y, Lee E W M. widening the sound absorption bandwidths of flexible micro-perforated curved absorbers using structural and acoustic resonances. INT J MECH SCI. 2007; 49:925-934.
32. Khavanin A, Sadeghi M, Mirzaei R, Safary A. The effect of apex angle on acoustic absorption coefficient in perforated sheet with pyramidal geometry. Journal of Acoustical Engineering Society of Iran. 2016; 4 (1) :21- 28URL:
33. Ågren A. The design and evaluation of a hemi-anechoic engine test room. Appl Acoust. 1992; 37: 151-161. URL:
34. Everest .F. A. Master Handbook of Acoustics .2001
35. Schroeder MR .Diffuse sound reflection by maximum length sequence. J Acoust Soc Am. 1975; 57:149- 50.
36. Schroeder MR. Binaural dissimilarity and optimum ceilings for concert halls: more lateral sound. J Acoust Soc Am. 1979; 65:958-63.
How to Cite
Monazzam MR, Hashemi Z. Investigating the Effect of Shape on Acoustic Performance of Micro Perforated Absorber at Low Frequencies. Int J Occup Hyg. 11(3):164-178.
Original Article(s)