Study on numerical simulation method for vibration characteristics of shell embedded with acoustic black hole

  Objectives  To study a numerical simulation method for a plate embedded with a two-dimensional acoustic black hole,

  Methods  a method for discrete modeling of the structure with acoustic black hole by a shell element is proposed. Firstly, an example of a plate embedded with a two-dimensional acoustic black hole is designed in this paper, a finite element model of the plate is established with a solid element, and the acoustic black hole effect of the plate is verified; secondly, the plate embedded with two-dimensional acoustic black hole is simulated with a shell element with the same size, and the modes and vibration responses obtained by the two modeling methods are numerically compared and verified; and finally, the influence of step change scale and power law of acoustic black hole region on the vibration characteristics of the whole structure are discussed.

  Results  The results show that it is reliable to calculate the accuracy of the vibration characteristics of the shell with acoustic black hole by means of shell element dispersion, and the shell element discrete method can reduce the computation scale and improve the computation efficiency compared with the solid element discrete method. At the same time, the reasonable adjustment of the step change scale and power law of the acoustic black hole region will influence the natural frequency of local modes.

  Conclusions  The research results can provide guidance for the design and application of the structure with acoustic black hole.