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2004, 3

Mohd Jailani Mohd Nor, Nordin Jamaluddin, Fadzlita Mohd Tamiri

A preliminary study of sound absorption using multi-layer coconut coir fibers

language: English

received 19.02.2004, published 27.03.2004

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Acoustic treatment using absorbing materials are widely used to reduce reverberation properties of closed spaces and to increase the transmission loss properties of multi-layer sound absorption panels. Natural fibers such as coconut coir fiber have high potential to be used as acoustic materials. As the natural fibers are agriculture waste, manufacturing natural product is therefore an economic and interesting option. This paper discusses the sound absorption using multi-layer coconut fiber as absorbing material component. The effect of microperforated plate and airspaces layers towards the sound absorption of the multi-layer construction was also investigated in this paper. Acoustic absorption coefficient is the main parameter to be estimated in this research. Computer simulation using WinFLAGTM program was done to calculate the acoustic absorption coefficients. Simulation indicated that multi-layer coconut coir fibers and airspaces could increase the acoustic absorption coefficient. All simulation results obtained are based on diffused sound incidence situation.

8 pages, 7 figures

Сitation: Mohd Jailani Mohd Nor, Nordin Jamaluddin, Fadzlita Mohd Tamiri. A preliminary study of sound absorption using multi-layer coconut coir fibers. Electronic Journal “Technical Acoustics”,, 2004, 3.


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Mohd Jailani Mohd Nor received his BSc degree in Mechanical Engineering and MSc degree in Mechanical Vibration from Oklahama State University, USA, in 1984 and 1988 respectively. He received his Ph.D. from Sheffield Hallam University, United Kingdom in 1996. Since 1986, he is an academic staff of the Department of Mechanical & Materials Engineering, Faculty of Engineering, Universiti Kebangsaan Malaysia. His research interest includes sound and vibration, machine condition monitoring using acoustic signals and most recently, Micro-Electro Mechanical System (MEMS) for automotive applications. He is currently an Assoc. Prof. and Deputy Dean (Academic) in the Faculty of Engineering, University Kebangsaan Malaysia.

e-mail: jailani(at)


Nordin Jamaludin received his BSc degree in Mechanical Eng. from University of Texas, El Paso, Texas, USA in 1987. Then he received a MSc degree in Applied Mechanics from University of Manchester Institute of Science and Technology, UK in 1990. In the year 2000, he obtained his PhD in Machine Condition Monitoring from Cranfield University, UK. He actively involved in the research of machine condition monitoring and diagnosis utilizing high frequency structure borne and air borne signals. He is currently an Associate Professor in the Dept. of Mechanical and Material Engineering, Faculty of Engineering, University Kebangsaan Malaysia.

e-mail: nordin(at)


Fadzlita Mohd Tamiri received her BSc degree in Mechanical Engineering from Universiti Kebangsaan Malaysia in 2002. She is currently pursuing her MSc degree in the same department and university. Her research field includes acoustic panel design and environmental acoustics.

e-mails: fadzlita(at), lita_tamiri(at)