车用发动机串并联分支结构进排气系统消声特性的研究

Research on the Muffling Characteristics of a Serial-Parallel Branched Inlet and Exhaust System for Automotive Engine

本文描述车用发动机进排气系统的声学模拟和分析过程,尤其对串并联分支管道系统和消声器进行了较为系统的声学研究。使用声学传递矩阵分析方法和声波有限元分析方法,将多输入输出的分支管道系统表示为相互连接的离散声学单元组合形式,离散声学单元两端的声压和声体积速度由传递矩阵唯一地联系起来。实际车用发动机复杂的串并联分支结构进排气系统都能用此方法进行模拟和分析,理论计算和实测结果表明:试验和理论具有良好的相关性和一致性。

This paper describes an acoustic modelling and analysis of an inletand exhaust system for automotive engine, in Particular, a systematicacoustic research on the piping and muffler system in serial-parallelbranch. By making use of acoustic transmission matrix analysis methodand acoustic wave finite element analysis method, a Piping system withmultiple branched inputs and outputs is represented by a combination ofdiscrete acoustic elements interconnected to one another at two ends.Theacoustic pressure and volume velocity at one end are uniquely relatedto those of the other by transfer matrix. More complicated practicalmultiply branched inlet and exhaust system in series or parallel for au-tomotive engine can be modelled and analyzed. The results show goodcorrelation and agreement of experiment and theory.