Investigation of Acoustic Efficiency of Wood Charcoal in Impedance Tube for Usage in Sound-Reflective Devices

Charcoal is an environmentally friendly, biodegradable, and economical material. This material usually produced by slow pyrolysis—the heating of wood or other substances in the absence oxygen. The aim this study was to investigate acoustic efficiency charcoal design diffuser that utilizes charcoal. Samples different types tree charcoal—birch (Betula pendula), pine (Pinus sylvestris), oak (Quercus robur)—with thicknesses were used for measurements. sound absorption reflection properties investigated. bulk density measured. In study, impedance tube with two microphones employed as measurement method. results measurements showed samples had high coefficients, highest value which 1. 50 mm birch a 473 kg/m3. sample thick best coefficient at 0.99. Reflection depended on surface’s properties, increased increase density. measurements, due material, diffuser, included wooden perforated plates filled cylindrical elements