Design and performance study of acoustic packaging materials for biomimetic coupled sound absorption structure in automobiles

Abstract This article studies the application of biomimetic triangular non-smooth surface materials in automotive acoustic packaging and their effects on sound absorption and insulation performance. Firstly, the application of Statistical Energy Analysis (SEA) in predicting high-frequency vibration noise in automobiles was discussed. Due to the limitations of the acoustic finite element method in predicting high-frequency noise, the SEA method has gradually been widely applied and continuously improved in domestic and foreign research. This article establishes SEA models for the front panel and floor. It analyzes the performance of different acoustic packaging materials through simulation, focusing on the sound absorption and insulation effects of biomimetic non-smooth surface materials. The experimental results show that the acoustic packaging material with a three-layer structure has excellent sound absorption and insulation performance in the high-frequency range. Specifically, the acoustic packaging of the cowl panel and floor adopts a three-layer material structure composed of organic fiber, molded felt, polyurethane foam and sound insulation felt. The simulation results show that the PU foam material with a bionic triangular wedge surface has a sound absorption coefficient of 0.983 at 1,000 Hz, significantly better than the traditional smooth surface material. In addition, the sound insulation performance of the front panel and floor increased by 2.9 dB and 48.1 dB, respectively, at 5,000 Hz.