Inverse methods of determining the acoustical parameters of porous sound absorbing metallic materials
Porous metal is now classified as one of the structural function materials, with the characteristics of ultra light weight, high specific strength and rigidity. As a sound absorbing metallic material, its acoustical parameters, especially such as the sinuosity factor, viscous and thermal characteristic lengths, are relatively difficult to obtain directly from the measurements under common experimental conditions. On the contrary, the sound reflection or absorption coefficient, and the normal surface acoustic impedance of porous metallic materials are easy to exactly measure in a standard acoustic impedance tube. As a result, this paper introduced the inverse methods in order to determine the acoustical parameters of porous metallic materials based on available sound absorbing models such as Johnson Champoux Allard (JCA) model, Biot Allard model, etc. Moreover, inverse methods based on Taboo search algorithm, simulated annealing genetic algorithm and linear regression (LR) were mainly presented, by means o.
Proc. Meet. Acoust.