Acoustic Properties of Innovative Material from Date Palm Fibre

Abstract

Problem statement: An organic material is one of the major requiremen ts to improve living environment and the invention of materials need to consider for the best solution. This study presents an experimental investigation on pure porous from D ate Palm Fibre (DPF). The effectiveness of sound absorbers depends on structural architecture of thi s material. This study was conducted to examine the potential of using date palm fibre as sound absorbe r. The effects of porous layer thicknesses, densiti es and compression on Acoustic Absorption Coefficient (AAC) of sound absorber using date palm fibre were studied. Approach: Rigid frame Johnson-Allard Model for various sample thicknesses was used in this study. The measurements were conducted in i mpedance tube on normal incidence acoustic absorption. The date palm fibre was mixed with late x which used for physical treatment on this material. Acoustic absorption behaviour of a porous material with different thicknesses was studied as well as samples with same thickness but different d ensities. In addition, samples with same properties but different period of compression time were inspe cted. The tests were in accordance to ISO 10534-2 and ASTM E1050-98 international standards for Acoustic Absorption Coefficient (AAC). Results: The experimental data indicates that two peak valu es of AAC is 0.93 at 1356Hz for sample with 50 mm thickness, also the AAC at high frequency for sa me thickness is 0.99 at 4200-4353 Hz that means able to improve acoustic absorption coefficient at low and high frequencies with significant increasin g. Meanwhile, another experimental results were acquir ed for AAC of date palm fibre, with samples thicknesses of 35 mm at different densities .The re sults show that denser sample (11 Kg m -3 ) has higher AAC value of 0.83 at 1934- 2250 Hz as compared to less dense sample (9.92 Kg m -3 ) with AAC value 0.84 at 2443-2587 Hz . Conclusion: Acoustic absorption coefficient AAC of date palm fibre was increased at all frequencies when the thi ckness of sample was increased, particularly at low frequencies less than 1200 Hz. The introduction of latex on the samples adds stiffness, so that sound can be dissipated significantly as it travels throu gh material. Results from the experimental tests sh ow that date palm fibre has good acoustic properties a t low and high frequencies and can be used as an alternative replacement to conventional product. In creasing density of the samples, increase the AAC as well. The innovative acoustic absorption panel has a good potential because they are cheaper and lighter in comparison to asbestos and rock wool ind ustrial materials.