Influence of Deformation on Sound-Absorbing Performance Under Hydrostatic Pressure

The sound-absorbing rubber coating is easy to deform under hydrostatic pressure, resulting in variation in acoustic properties. For improving the accuracy of the deformation of the sound-absorbing structure under hydrostatic pressure, four hyperelastic constitutive models of Mooney-Rivlin, Neo-Hookean, Yeoh and Arruda-Boyce were selected in fitting the tensile curve of the dumbbell specimen and the compressive curve of a cylindrical specimen. The comparison in their applicability and the accuracy showed that the Yeoh model can predict the compressive properties of carbon black filled styrene-butadiene rubber. Simulation in mechanics-sound coupling was further conducted by COMSOL software and verified by the acoustic experiments, which exhibit the non-negligible effects of pressure and tubes inserted in the cavities on the deformation and sound-absorption coefficient. Hydrostatic pressure exerts the deformation and thereafter the energy dissipation in sound transfer. Inserting a rigid tube is beneficial to improve the ability of the sound-absorbing tile to resist deformation and enhance sound absorption and dissipation. The sound absorption coefficient was above 0.4 in the frequency band above 1.5kHz even under the hydrostatic pressure of 2MPa. The numerical simulation provides one methodological reference in analyzing the influences of the structural change and the operational conditions on the sound-absorbing coating.