Analysis of acoustic and vibration characteristics of polyurea-coated novel elliptical annular re-entrant auxetic honeycomb

A novel honeycomb core design combining elliptical annular structures with re-entrant hexagonal structures was proposed, and a new auxetic honeycomb sandwich panel coated with polyurea was developed to enhance its vibroacoustic performance. A numerical model of the novel auxetic honeycomb sandwich panel was established using ABAQUS software and validated. The vibration and acoustic responses of four different configurations of the novel auxetic honeycomb sandwich panel were analyzed through numerical simulations. The results indicate that the polyurea coating location and honeycomb geometry enable the sandwich panel to effectively reduce vibration and suppress noise. The symmetric structure (P-4 panel) of the honeycomb sandwich configuration outperforms the asymmetric structures in both vibration reduction and sound insulation. The sandwich panel with a 6 mm polyurea coating exhibits the lowest peak and fastest decay in sound pressure level (SPL), along with a 7.6% improvement in average sound transmission loss (STL). The honeycomb geometries α = 1 and μ = 1 demonstrate the most superior vibroacoustic characteristics in the sandwich panel.