Abstract: Automobile muffler is the most important part in reducing automobile noise pollution. It plays an important role in passenger comfort, environmental protection. This paper first analyzes the basic equations of acoustic wave movement in air, and the muffler is modeled in 3D by CATIA software. Then, virtual. lab software is used to solve the sound field in the muffler cavity by finite element method. And the sound pressure distribution in the sound field inside the muffler and the sound transfer loss performance of the muffler are obtained. Finally, the improvement measures of muffler structure are proposed according to the simulation results, and the back pressure experimental test of the muffler is also carried out. It provides theoretical basis and reference for muffler structure design.

Key words: Automobile muffler; Automobile noise; Back pressure; Simulation analysis; Structure design

摘要： 汽车消声器是减少汽车噪声污染中的最重要部件，它对提升乘坐舒适性、保护环境有 着很积极的意义。论文首先分析了空气中声波运动的基本方程，同时采用 CATIA 软件对消声 器进行了三维建模。然后采用 virtual.lab 软件对消声器内部空腔声场进行有限元求解，获得 了消声器内部声场中的声压分布及消声器的声传递损失性能。最后根据仿真结果提出消声器 结构改进措施，此外还对消声器进行背压实验测试。研究结果可为消声器结构设计提供理论 依据与参考。

关键词: 汽车消声器；汽车噪声；背压；仿真分析；结构设计