Non-local boundary control for broadband non-reciprocal propagation analytical demonstration and experimental validation
Résumé
The semi-active impedance control techniques can offer new perspectives for acoustic treatment in the nacelle inlet of the new generation of Ultra-High-By-Pass-Ratio turbofan engines. In this contribution we present a non-local boundary condition capable of achieving broadband nonreciprocal propagation in a waveguide, envisaging the possibility of energy harvesting, other than acoustic transmission attenuation. The non-local boundary control concept is first illustrated analytically, and then it is implemented experimentally through a liner of electroacoustic devices.