Numerical Investigation of Dynamic Properties of The Beam with Segmented Acoustic Black Hole Indentations

Abstract

Embedding an acoustic black hole (ABH) in a thin-walled structure can help the system achieve vibration damping and energy gathering. Nevertheless, due to the limitations of processing and manufacturing technology, there will always leave a truncation at the tip of ABH region, which brings many undesirable impacts and makes ABH effect greatly reduced. In this paper, segmented ABH structure is proposed and applied to the Euler–Bernoulli beam. Dynamic properties of different forms beam are investigated through finite element based method, and the result shows that segmented ABH structure has better vibration attenuation and energy gathering effect. In addition, the velocity distribution and the kinetic energy ratio have also been calculated. The calculation results show that segmented ABH beam can better gather energy on the tip of ABH structure and achieve higher kinetic energy ratios in the mid to high frequencies, which further reveal the underlying mechanism of better ABH effect of segmented ABH structure. The research of this paper mainly provides a new idea around how to reduce undesirable impacts of truncation and looks forward to promote the application of ABH beam structures in engineering.