A Study on the Acoustic Properties of Glass Fiber-Melamine Foam Composites Based on TMM and FE-SEA

Abstract

To address the challenge of broadband noise control in electric vehicle doors under the constraints of narrow installation space and lightweight design, this study focuses on unreinforced glass fiber-melamine foam (GF-MF) composites and systematically investigates their acoustic performance regulation mechanisms and engineering structural design for vehicle door applications. Combining the Transfer Matrix Method (TMM) with impedance tube experiments, the effects of porosity, air backing layer thickness, and flow resistivity on the acoustic coefficients of the material were analyzed. A hybrid Finite Element-Statistical Energy Analysis (FE-SEA) model was established to evaluate the sound transmission loss (STL) of five door composite layup schemes under diffuse incidence conditions. The results demonstrate that high porosity significantly optimizes the impedance matching characteristics in the mid-to-high frequency range and enhances broadband sound absorption efficiency, while high flow resistivity effectively strengthens the viscous dissipation capacity in the mid-to-low frequency range. Among all structural layup schemes, the pure air layer scheme yields the highest STL across the full frequency band. Adding a 2 mm viscoelastic damping layer on the outer door panel side further improves low-frequency sound insulation performance. In contrast, positioning the damping layer adjacent to the GF-MF side or adopting a honeycomb sandwich structure leads to acoustic performance degradation. This research elucidates the acoustic parameter regulation laws of glass fiber-melamine foam (GF-MF) composites and the optimization strategies for vehicle door layup designs. A systematic comparative analysis of five layup schemes under identical thickness constraints is conducted. The findings provide practical engineering guidance for the development of lightweight, thickness-constrained acoustic packages in electric vehicle door systems.