Research on Optimization of Acoustic Packaging Performance of Electric Vehicle Motor Compartment Based on Transfer Matrix Theory

This study addresses the prevalent issue of inadequate low-frequency sound absorption within electric vehicle motor compartments by introducing a novel multi-layer composite acoustic structure characterized by a gradient flow resistance design, grounded in transfer matrix theory. An acoustic transmission model was developed, and the proposed design was evaluated through both simulation and experimental validation. Results indicate that the gradient flow resistance configuration enhances the sound absorption coefficient by 15 – 20 % compared to conventional single-layer materials within the 200 – 500 Hz low-frequency range, while achieving a sound absorption coefficient exceeding 0.9 at higher frequencies. Furthermore, the application of a simplified transfer matrix model reduces computational complexity by approximately 30 % without compromising accuracy. This research offers a pioneering design methodology for acoustic packaging solutions in electric vehicle motor compartments.