In general when sound waves strike on the surface of porous materials sound energy could get channelized as.
Absorption coefficient of hardwood.
The noise reduction coefficient ranges between 0 40 and 0 75 depending on the slot pattern and installation.
The length and pattern of the slots cut through the panels influence their absorption of soundwaves.
Generally speaking soft porous materials will be more absorptive than hard reflective surfaces.
Absorption coefficients are an average of how absorptive each product is at numerous frequencies generally at 500 hz 1000 hz and 2000 hz.
Hardwood burning was identified as the dominant source of carbonaceous aerosols.
Absorption transmission and reflection.
For hackberry hardwood species the better sound absorption coefficient is identified in a wide frequency range of 2 khz 6 khz due to the presence of more pores and larger passageway.
Sound absorption coefficient greater than 1 01 sound absorption coefficient greater than 1 02.
Slotted wood panels can be used on walls or ceilings to reduce the noise and echo within a room or building.