Scientific Development
Sound Absorption Performance of Natural Fibers And Their Composites

YI Xiaosu1, LI Yan2, HE Delong1
1 AVIC Beijing Institute of Aeronautical Materials, PO Box 81, Beijing, 100095 (P.R. China)
2 Tongji University, SHANGHAI 200092, PR China



This research aims to study the sound absorption properties of natural fibers and their reinforcing composites. Sound absorption coefficients of three types of natural fibers, i.e., ramie, flax and jute fibers and their composites were measured by two-microphone transfer function technique in the impedance tube. The results were compared with those of synthetic fibers and their reinforcing composites. It is found that both natural fibers and their composites have the superior capability for noise reduction. The multi-scale and hollow lumen structures of natural fibers contribute to the high sound absorption performance. Moreover, the sound absorption properties of these natural fibers were also calculated by the Delany-Bazley and Garai-Pompoli models. The calculation results showed good agreement with the experimental data. It was indicated that composite materials integrating good mechanical properties and acoustic functions can be made by natural fibers reinforced polymers.

Keywords:Natural fiber reinforced composites, Sound absorption, Impedance tube