Sound Absorption Performance of Sugar Palm Trunk Fibers

¹ Mechanical Engineering Department, Engineering Faculty, Sebelas Maret University, Jl.Ir Sutami No.36 A, Surakarta, 57126 Indonesia
² Acoustic Laboratory, Engineering Physics Department, Bandung Institute of Technology, Jl.Ganesha No.10, Bandung, 40116 Indonesia

^* Corresponding author: kuncorodiharjo@ft.uns.ac.id

Abstract

The purpose of this research is to investigate the effect of bulk density, thickness, and air gap to sound absorption performance on absorber based sugar palm trunk fibers. The fibers were obtained from solid waste on Small-Medium Enterprises of sago flour processing in Klaten, Central Java, Indonesia. The absorber specimens were formed from the fibers using a simple press molding in an oven at 150 °C. According to ISO 10534-2, the absorber samples were tested using two microphones impedance tube with random noise source to get the curve of the sound absorption coefficient. The result shows that the absorption performance can be improved by increasing bulk density and increasing of sample thickness. Especially at low frequencies, improvement of the sound absorption coefficient can be achieved (NAC > 0.8) by applying the air gap behind the sample. The best performance of absorber based sugar palm trunk fiber can be achieved for (1 000 to 6 000) Hz range frequency.