Materiales de Construcción, Vol 64, No 313 (2014)

A model for acoustic absorbent materials derived from coconut fiber

J. Ramis
Universidad de Alicante, Spain

R. del Rey
Universitat Politècnica de València, Spain

J. Alba
Universitat Politècnica de València, Spain

L. Godinho
CICC, University of Coimbra, Portugal

J. Carbajo
Universidad de Alicante, Spain


In the present paper, a methodology is proposed for obtaining empirical equations describing the sound absorption characteristics of an absorbing material obtained from natural fibers, specifically from coconut. The method, which was previously applied to other materials, requires performing measurements of air-flow resistivity and of acoustic impedance for samples of the material under study. The equations that govern the acoustic behavior of the material are then derived by means of a least-squares fit of the acoustic impedance and of the propagation constant. These results can be useful since they allow the empirically obtained analytical equations to be easily incorporated in prediction and simulation models of acoustic systems for noise control that incorporate the studied materials.


Acoustic impedance; Absorption coefficient; Natural fibers; Empirical models

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