EVALUASI KINERJA AKUSTIK SERAT ALAM SEBAGAI MATERIAL ALTERNATIF PENGENDALI KEBISINGAN

• Main Author: Sabri
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/5456
• Institution: Institut Teknologi Bandung

<b>Abstract:<p align=\"justify\"><br /> Sound absorption materials are generally classified into three types; porous, absorbent panel and cavity resonator. All of these three types are based on the process of energy transforming from sound energy to thermal energy. The characteristic of sound absorbers can he stated in sound absorption coefficient for each incidence frequency. Generally, absorbent materials have absorption coefficient just in a certain frequency.<p align=\"justify\">In this research would be examined the acoustic performance of coir and jute fibres for the purpose of substituting the conventionally used materials such as rockwool and glasswool. The used of natural fibres (indigenous materials) have many advantages compared to conventional sound absorbers, including reduced production cost, good handling and environmental protection.<p align=\"justify\"> The sound absorption performance of coir and jute fibre was determined experimentally using a reverberation chamber conforming to the ISO 354 (1985) standard. The results indicate that the sound absorption coefficient is a function of incidence frequency and the angle of incidence sound wave. The maximum absorption coefficient was reached in the value of 90 % at 4000 Hz, while for jute fiber was reached in 77 % at frequency 5000 Hz. <p align=\"justify\">For the panels of coir and jute, the frequency spans of sound absorption would become wider. This is caused by the existence of air cavity behind the test specimen. The sound absorption coefficient for coir panel with air cavity depth of 4 cm was above 80 % ranging from 500 Hz to 5000 Hz, while for jute panel ranged from 630 - 3150 Hz. The existence of air cavity behind the samples have increased the sound absorption coefficient significantly<p align=\"justify\">