SOUND ABSORPTION PROPERTIES OF RECYCLED POLYESTER FIBROUS ASSEMBLY ABSORBERS

Abstract Sound absorption materials are generally classified into three types, porous, resonator, and panel. All of these three types are based on the theory of energy transforming from sound energy to thermal energy. In this paper, we examined the sound absorption coefficient of recycled polyester nonwovens for the purpose of substituting the conventionally used materials such as glasswool and rockwool. The use of recycled polyester nonwovens has many advantages compared to conventional sound absorbers, including reduced product cost, good handling, and environmental protection. The sound absorption coefficient of the recycled polyester nonwovens was determined by a two-microphone impedance measurement tube; the determination of the noise absorption coefficient is nothing more than the absorption energy rate of the material against the incidence energy. We have determined the relationship between the acoustic absorption values measured and the nonwoven parameters including fibre properties and web properties.