EXPERIMENTAL STUDY ON NATURAL FIBRES FOR GREEN ACOUSTIC ABSORPTION MATERIALS

Abstract

Natural fibre materials are one of the major ways t o improve environmental pollution and new materials need to be considered to find the best solutions. T his study presents an experimental investigation on pure micro porous materials from two types of fibers: Da te Palm Fibre (DPF) and Coconut Coir Fibre (CCF). This study was conducted to examine the potential f or using these two types of fibers as sound absorbe rs. To account for the effects of the characteristics o f these materials, such as thickness and density, o n the acoustic absorption coefficient of a sound absorber , the measurements were conducted in an impedance tube on normal incidence acoustic absorption. The experi mental data indicate that two peak values of Acoust ic Absorption Coefficient (AAC) are 0.98 at 1381.25 Hz-1506.25 Hz for the 40 mm thick sample and the AAC at high frequency for the same thickness is 0.9 9 at 4521.88-4906.25 Hz; for 20 mm thickness, the peak value is 0.84 at 2606.25-3025 Hz. The AAC of the CCF sample is 0.77 at 2434.38-2543.75 Hz for a 40 mm thickness, but for 20 mm thickness, the value is 0.71 at 4184.38-4575 Hz. The Acoustic Absorption Coefficients (AAC) of the two types of materials we re increased at all frequencies when the thickness of the sample was increased. The results show that date pa lm fibre and coconut coir fibre have good acoustic properties at low and high frequencies and can be u sed as an alternative replacement to conventional products. The comparisons between the two panels show a good potential because they are cheaper and lighter in comparison to asbestos and rock wool ind ustrial materials.