Study on vibration reduction performance of one-dimensional acoustic black hole with different thickness functions

Abstract

The acoustic black hole structure is used for high-frequency vibration and noise reduction of the structure. It uses the gradient change of the geometric parameters of the thin-walled structure or the material characteristic parameters to gradually reduce the propagation speed of the wave in the structure and cannot reach the boundary. Realize vibration reduction and noise reduction of elastic waves and energy recovery. As an effective method to deal with many vibration and noise reduction problems, acoustic black holes are currently being studied by many scholars as a hot topic. Most of the studies are based on the thickness variation law as a power function. However, more in-depth research has not been carried out on the acoustic black hole structure whose thickness variation law is other functions. In this paper, the finite element simulation method is mainly used to study the vibration reduction effect of the acoustic black hole structure with four function laws: the traditional quadratic power function, the trigonometric function, the exponential function and the logarithmic function, and compare the four function laws. Vibration reduction effect of one-dimensional acoustic black hole beam structure. The research and calculation results show that in the one-dimensional acoustic black hole beam structure with four function laws, the logarithmic function has a better vibration reduction effect in the low frequency range, while the power function is the best choice in the middle and high frequency range. It provides a certain reference value for the design and selection of acoustic black hole structures in different frequency bands in the future.