Open AccessThe Evaluation of Deviation in Sound Absorption Coefficient for Micro – perforated Panel
Author(s) -
Nur Arafah Jafar,
Lu Ean Ooi,
Ahmad Zhafran Ahmad Mazlan,
K. H. C. Seng,
Jinglu Tan
Publication year - 2020
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/815/1/012009
Subject(s) - noise reduction coefficient , materials science , microphone , attenuation coefficient , acoustics , absorption (acoustics) , brass , standard deviation , laser , acoustic impedance , optics , composite material , mathematics , porosity , physics , sound pressure , statistics , ultrasonic sensor , copper , metallurgy
In this paper, the sound absorption coefficient for micro-perforated panel (MPP) is conducted to determine the acoustic properties of MPP. Two different kind of MPP with the same parameter is used. One is Nylon material and another one is Brass material. Both are fabricated by using 3D Printing technology and Laser Cut process respectively. The sound absorption coefficient of both 3D Printed Nylon MPP and Laser Cut Brass MPP is measured with two-microphone method by using Impedance Tube. The calculated sound absorption coefficient is done by using MATLAB software based on the Classic Maa model. The measured sound absorption coefficient is compared with the calculated result for both MPP. The comparison results show some deviation, like measured results produce a big dip, absorption peak frequency shifted towards higher frequency and wider absorption bandwidth observed when compared to the calculated result. In conclusion, it is found out hole imperfection effect is one of the reasons to the deviation produce between the compared result.