Influence Of Different Distribution Patterns Of Holes On Single Micro-Perforated Panel Sound Absorption Behaviour

Authors

  • Hatem Teleb Assistant Researcher https://orcid.org/0000-0003-3795-007X
  • Mohamed Abd-Elbasseer Acoustics Laboratory, National Institute of Standards (NIS), Giza, Egypt
  • Abd Elfattah A Mahmoud Acoustics Laboratory, National Institute of Standards (NIS), Giza, Egypt
  • Hatem Kh. Mohamed Acoustics Laboratory, National Institute of Standards (NIS), Giza, Egypt

Keywords:

Micro-Perforated Panel Absorber, Distribution Pattern, Hole Geometry, Maa Model.

Abstract

Micro-perforated panels have become a valid broadband sound absorber option lately. Their applicability is wide since they are promising for absorbing sound energy for several applications, such as automotive, HVAC systems, noise barriers, etc.  This study investigates the effect of different distribution patterns of holes, perforation ratio, air gap depth, and the hole geometry on single micro-perforated panels' sound absorption behavior. Four different distribution patterns (Circle, Square, Triangle, and Random) of orifices are designed and fabricated on a surface of metal sheet of thickness 1 mm with hole diameter 1mm, and air gap depth between the panel and the back wall 100 mm. Each distribution pattern of the four different patterns was perforated with seven perforation ratios (0.12%, 0.36%, 0.48%, 0.60%, 0.84%, 1.1%, and 1.9%).The measurements were carried out using the two-microphone impedance tube in the low-frequency range from 100 Hz to 1000 Hz. Although the results revealed no significant difference between the absorption coefficients of different holes' patterns at all the perforation ratios, the random pattern is slightly higher than other distribution patterns. Increasing the air gap depth improved the average sound absorption coefficient in the frequency range from 160 Hz to 630 Hz from 0.29 to 0.51. Moreover, Changing the hole geometry from circle to square and triangle enhanced the sound absorption coefficient of about 11 % and 12 %. Good consistency between the theoretical calculations and the experimental results is obtained.

Published

2021-07-07

How to Cite

1.
Teleb H, Abd-Elbasseer M, Mahmoud AEA, Mohamed HK. Influence Of Different Distribution Patterns Of Holes On Single Micro-Perforated Panel Sound Absorption Behaviour. Canadian Acoustics [Internet]. 2021 Jul. 7 [cited 2021 Sep. 25];49(2). Available from: https://jcaa.caa-aca.ca/index.php/jcaa/article/view/3416

Issue

Section

Article - Engineering Acoustics / Noise Control