High acoustic absorption properties of hackberry compared to nine different hardwood species: A novel finding for acoustical engineers

Abstract

Wood is one of the most usable natural composite. Noise pollution from the various sources affect the human health and environment worldwide. How to reduce noise pollution has become a major issue? Hence, finding the proper sound absorbing wood is necessary for improved acoustic environment. In the present work, we choose most useful ten different hardwood species. Analysis of basic properties, surface morphology by HR-FESEM, elemental analysis using EDAX, cellulose crystallites by XRD, air permeability by a capillary flow porometer, sound absorption coefficient and sound transmission loss by microphones transfer function method using impedance tube is discussed in detail. The Hackberry wood shows better sound absorption coefficient (0.640 at 4000 Hz), sound transmission loss (15.23 at 4000 Hz) due to the higher value of Darcy permeability constant (9.78), porous surface morphology and lower cellulose crystallites (16.6%). These results became extremely important to the engineers for designing good acoustic housing environment.