Ultralight micro-perforated sandwich panel with hierarchical honeycomb core for sound absorption

A theoretical model is developed to study the superior sound absorption performance of ultralight mirco-perforated sandwich panels with double-layer hierarchical honeycomb core. Numerical simulations are performed to validate theoretical model predictions and explore physical mechanisms underlying the sound absorption. Systematic parametric study is implemented to investigate the influence of specific structural parameters on sound absorption. To maximize sound absorption, optimal structural parameters of the hierarchical sandwich are obtained using the method of simulated annealing. It is demonstrated that viscous dissipation of the air inside micro-perforations and around inlet/outlet regions dominates sound absorption. Compared to micro-perforated sandwich panels with regular honeycomb core, not proposed hierarchical construction has much improved load-bearing capacity, but also significantly enhanced sound absorption covers a wide range of frequency.

Automated summary

This study investigates the superior sound absorption performance of ultralight micro-perforated sandwich panels with double-layer hierarchical honeycomb core. Theoretical model predictions and numerical simulations validate the physical mechanisms underlying sound absorption, with systematic parametric study revealing optimal structural parameters for maximizing sound absorption. Viscous dissipation of air inside micro-perforations and around inlet/outlet regions is shown to dominate sound absorption, while the proposed hierarchical construction offers improved load-bearing capacity and significantly enhanced sound absorption across a wide frequency range compared to panels with regular honeycomb core.