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Description
Low frequency noise mitigation can be hardly conducted using fully passive materials at the cost of very cumbersome and expensive set-ups. Many alternatives exist, among them, active noise control enables the use of energy to enhance noise mitigation of electro-mechanical devices. Using a model inversion technique, the first mode’s parameters of a loudspeaker can be tuned for efficient acoustic passive mitigation at low frequencies. However, linear behaviors offer limited performances, while nonlinear behaviors benefit from good performances over a large frequency bandwidth, in addition to targeted energy transfer and fast transients behaviors. The main drawback of nonlinear behaviors is their activation threshold at very high excitation amplitudes that can be circumvented using model-inversion pressure-based current-driven control techniques, enabling to create nonlinear behaviors at low excitation amplitudes. This study presents the development of a nonlinear metasurface composed of individual nonlinear electroacoustic resonators at low excitation amplitudes. Numerical analysis is conducted and an experimental bench composed of a waveguide and seven electroacoustic resonators is introduced and show excellent transmission loss performances.