Artificial cochlea and acoustic black hole travelling waves observation: Model and experimental results

• DOI: 10.1016/j.jsv.2014.03.016
• Publication Date: 2014-04-13T11:15:20Z
• Authors: Simon Foucaud; Guilhem Michon; Yves Gourinat; Adrien Pelat; François Gautier
• Keywords: Reflection; Waveguide

An inhomogeneous fluid structure waveguide reproducing passive behaviour of the inner ear is modelled with the help of the Wentzel–Kramers–Brillouin method. A physical setup is designed and built. Experimental results are compared with a good correlation to theoretical ones. The experimental setup is a varying width plate immersed in fluid and terminated with an acoustic black hole. The varying width plate provides a spatial repartition of the vibration depending on the excitation frequency. The acoustic black hole is made by decreasing the plate׳s thickness with a quadratic profile and by covering this region with a thin film of viscoelastic material. Such a termination attenuates the flexural wave reflection at the end of the waveguide, turning standing waves into travelling waves.