Analysis on Vibration Suppression Performance of an Attached Acoustic Black Hole Composite Beam

Abstract Attaching damping to structures is a common vibration suppression measure. Different from attaching uniform thickness damping, this paper proposes an acoustic black hole damping attached to a beam. There is an internal cavity between the beam and the damping layer. The thickness of the internal cavity is designed to vary according to a power index gradient, forming an attached acoustic black hole composite beam. Combined with the energy and virtual spring method, the theoretical model of the ABH beam following the Euler-Bernoulli beam theory is established to calculate its vibrational response. The vibration displacement response of the ABH beam is calculated using the finite element method again. The correctness of the theoretical model is confirmed by contrasting the theoretical results with the finite element results. From the comparison, it can be found that the peak frequency of the vibration displacement level at the output end of the ABH beam moves toward the higher frequency, and the peak response value is lower compared to that of the uniformly damped beam. The attenuation frequency interval shifts to the higher frequency in the vibration displacement transfer response curve. It can be concluded that the ABH beam exhibits better vibration suppression performance than that of the uniformly damped beam with identical damping thickness.