Nonlinear Sound Absorption Performance of Metal Rubber Material

Nonlinear sound absorption performance of metal rubber material under corrosive medium, big temperature change, and other extremely severe conditions is presented. Nonlinear complex density and particle velocity equation are developed based on metal rubber (MR) material linear theory and Forchheimer's correction method. A model for solving sound absorption parameters is developed under two sound absorption boundary conditions known as hard backed walls and samples with air layers. Relationship between structure parameters as well as incidence pressure level and nonlinear sound absorption performance is studied by theoretical calculation and experimental approach. The results indicate that nonlinear sound absorption performance of MR varies with incidence pressure level and structure parameters, respectively. With the increase of the thickness and static flow resistivity of MR samples, the MR material exhibits much less nonlinear sonic effect. copyright 2010 Journal of Mechanical Engineering.