Design and analysis of a microlattice structure for enhanced broadband sound absorption

This paper presents a novel microlattice structure designed for enhanced broadband sound absorption, leveraging the integration of a body-centered cubic (BCC) lattice with a triply periodic minimal surface (TPMS) I-Wrapped Package (IWP). The proposed microlattice sound absorber (MSA) features a hollow, two-stage parallel-coupled structure, which introduces multi-frequency dissipation components, achieving tunable and broadband sound absorption across a wide frequency range. The study employs both the LRF and JCA models to derive acoustic performance, and results are validated through numerical simulations and impedance tube experiments, demonstrating good agreement. Additionally, parametric analysis results demonstrate that increasing material thickness and reducing unit cell size can enhance overall sound absorption performance. Increasing the depth of the reserved back cavity can lower the peak frequency of the first-order sound absorption. The developed MSA structure is further applied in a muffler system, exhibiting broadband noise reduction and excellent ventilation performance. This research contributes a customizable and efficient approach to noise control, suitable for extreme environments, with broad applications in engineering fields such as aerospace and automotive industries.