Targeted Nonlinear Energy Transfer for Electroacoustic Absorbers

Abstract

In order to investigate the effects of coupling a nonlinear electrical shunt circuit to a loudspeaker terminal, a representative two degrees of freedom (dof) system has been considered. It consists of a main system describing the displacement of the loudspeaker membrane, which is linearly coupled to a Nonlinear Energy Sink (NES) with a small mass compared to the principal one. An analytical treatment enabling the analysis of the behaviour of the system around the 1:1 resonance at different time scales is endowed. This methodology enables the detection of equilibrium and singular points, corresponding to periodic and modulated regimes, respectively. The analytical developments prepare necessary design tools for tuning parameters of the NES.