汽车前围板声传递特性分析

Vibration and noise experiment of aluminum plate/rectangular cavity coupling system is designed to validate the Coupled Indirect Boundary Element Method is satisfactory for vibro-acoustic analysis of flexible plate/enclosure coupling system under acoustic excited. Based on this method, the model involved three domain of engine cavity-firewall-passenger cavity is built to investigate sound transmission characteristic of the firewall in the low-frequency range. In this model, the engine radiated noise was simplified by random white noise. Subsequently, the influence of different metal plate material and multi-layer sound material on the firewall sound transmission was analysised.The results show that the sound insulation characteristic of the firewall with lightweight material instead of steel would decrease.The sound insulation characteristic was improved by laying the sound insulation material above 150Hz.