Sound absorption and form retention of newly developed heat-insulating/acoustic material

A wooden mat to be used as heat-insulating/acoustic material was developed using wood shavings in their raw curled flake form as the primary material. This report discusses the influences of fabrication conditions on sound absorption and form retention. The results showed that the form retention was increased with kenaf composition. However, the normal incidence absorption coefficient decreased with increasing kenaf composition and improved with increasing shavings composition. The increase of airflow resistivity was shown as the reason. Moreover, element’s internal loss of solid-borne sound transmission and the influences of various acoustic parameters that the shape of the element brought were considered as the reason. Sound absorption coefficient in a reverberation room was measured under optimum fabrication conditions, and the performance of the mat was found to be approximately equal to that of glass wool.