Abstract：using the transmission equation of acoustic in the layered media, the recursive formula of absorption coefficient of multi-layered structure is given. Then, for the double layer structure made of porous sound-absorbing material, the effect of acoustic parameters including the thickness, porosity and pore radius of each layer on the absorption coefficient is analyzed by numerical calculation. Based on the recursive formula, parameter optimization of the multi-layered sound absorbing structure is investigated. It shows that the multi-layered sound absorbing structure made of porous sound-absorbing material has good sound absorption and can afford sufficiently satisfying sound absorption level in a cared frequency range. The results provide a theoretical support for product design.
2012, Vol. 31 
