汽车消声器声学性能仿真分析

Acoustic Performance Analysis on Vehicle Muffler

基于LMS Virtual Lab声学软件,建立以六面体为主的非网络结构单元,利用建立传递导纳的关系来模拟具有大量微小穿孔的穿孔板两侧的声学关系。虽然建立模型的过程所耗费的工作量较大,但是它与四面体的网格相比,最大的优势在于可以通过建立传递导纳关系来避免对具有大量微孔结构的抗性消声器划分网格。运用声学有限元的方法侧重对某种型号汽车消声器的插入损失和传递损失进行了仿真研究,从定性上对消声器的性能进行了理论上的验证,为优化设计提供理论依据。

Based on the acoustic FEM software LMS Virtual Lab,the 3D model of the silencer is discretized into hexahedron unstructured mesh elements,with establishing admittance function to simulate the transmission relationship between outside surface and inside surface of perforated pipes with a large quantity of micro holes.Its greatest advantage is capacity of establishing admittance function to simulate the case of perforated plate instead of discretizing the fluid domain around a large number of micro holes while the mesh of tetrahedron elements is not capable to realize it.It mainly studied on insert loss and transmission loss of the muffler by the method of acoustic FEM,and verified the acoustic performance of the muffler theoretically,and provided a theoretical basis for the optimization design.