Nonlinear propagation in acoustic networks
Résumé
Nonlinearity, dispersion and dissipation are well known to play a key role in wave propagation, and in many physical systems these mechanisms coexist. One of the most interesting phenomena which stems from the balance of dispersion and nonlinearity is the emergence of solitons, namely robust localized waves propagating undistorted in nonlinear dispersive media. In this work we study the propagation of high- amplitude sound waves in acoustic networks. In particular, we experimentally demonstrate the formation of solitary waves in one dimensional periodic waveguides, despite the presence of nonlinear losses. Furthermore, for a two dimensional square network of connected waveguides, we show analytically and numerically the existence of anisotropic cylindrical solitary waves. Finally, we show that the inclusion of Helmholtz resonators in the network "heals" the anisotropy, consequently transforming the anisotropic cylindrical solitons to isotropic ring solitons.