PEKALI PENYERAPAN BUNYI DAN INDEK KEHILANGAN PENGHANTARAN PANEL PENYERAP BUNYI MENGGUNAKAN GENTIAN SABUT KELAPA

This study was carried out to determine the acoustic properties of a noise absorption panel that was designed to use a coir fibre as noise absorption materials through experimental test and simulation. Comparison of noise absorption coefficient between natural coir fibre and coir fibre inserted inside a perforated panel have been carried out. The outer layer of the panel was fabricated using a coir fibre/polyester composites and treated coir fibre was used as absorption materials. The panel has been tested using ISO 354 standard for noise absorption coefficient while the simulation was carried out using WinFLAGTM software. The transmission loss index test for panel using coir fibre has been carried out and the results were compared with panel using an oil palm fibre. For the transmission loss index, ISO standard 717-1 was used. Experimental results for the noise absorption coefficient give coefficient values between 0.70 and 0.80 for frequency range of 1000 Hz to 1800 Hz while the results from simulation give a coefficient between 0.7 to 0.85 for frequency range of 500 Hz to 2500 Hz. For the transmission loss test, average transmission loss recorded was 20 dB for the panel using coir fibre and 17 dB for panel using an oil palm fibre. Results show that sound absorption coefficient obtained through experimental test and simulation were very good and comparable with the commercial noise absorption material such as synthetic fibre and rock wool. Transmission loss index for the panel using coir fibre gives better results compared to panel using oil palm fibre.