Electrically tunable and broader-band sound absorption by using micro-perforated dielectric elastomer actuator

Most membrane-type acoustic absorbers for low-frequency sound attenuation are applicable only at a fixed resonant frequency for a narrow bandwidth. Tuning of the acoustic absorption spectrum is desired to match the varying noises. This letter presents a micro-perforated dielectric elastomer actuator...

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Bibliographic Details
Main Authors: Lu, Zhenbo, Shrestha, Milan, Lau, Gih-Keong
Other Authors: School of Mechanical and Aerospace Engineering
Format: Journal Article
Language:English
Published: 2017
Subjects:
Online Access:https://hdl.handle.net/10356/83352
http://hdl.handle.net/10220/42567
Description
Summary:Most membrane-type acoustic absorbers for low-frequency sound attenuation are applicable only at a fixed resonant frequency for a narrow bandwidth. Tuning of the acoustic absorption spectrum is desired to match the varying noises. This letter presents a micro-perforated dielectric elastomer actuator (MPDEA) to make a broader-band acoustic absorber electrically tunable. Voltage activation of the MPDEA reduces the membrane tension and hole size and thus enables the active shifting of the acoustic absorption spectrum. Such a membrane tuning method does not require discrete mechanical parts as for the cavity tuning method. Also presented are the analytical models to predict the voltage-induced hole size change and acoustic characteristics of MPDEA.