某车辆排气系统动态特性计算，测量及分析

为分析某车辆排气系统的动态特性,对其分别利用计算模态分析技术和测量模态分析技术进行了研究,获得了该排气系统的前六阶计算模态参数和测量模态参数。通过对比发现前六阶固有频率计算和测量结果误差小于6.5%,振型基本一致。进而根据计算和测量结果分析了该排气系统动态特性,发现该车辆在发动机怠速与经济转速激励下均不会发生共振,并且分析了该排气系统动态特性设计的薄弱环节。研究方法与结果对于汽车排气系统动态特性设计具有一定指导意义。

Calculation, measurement and analysis for dynamic characteristics of a vehicle exhaust system

In order to analyze the dynamic characteristics of the vehicle exhaust system, it is studied by calculating modal analysis and experiment modal analysis technique, respectively.The first six order modal parameters of the exhaust system are obtained.By comparison, it is found that the error of the first six-order natural frequency calculation and the experimental result is less than 6.5%, modal shapes are basically consistent.Then the dynamic characteristic of the exhaust system is evaluated according to the result of calculation and experiment.It is found that the vehicle exhaust system will not occur resonance under the excitation of resonance in idle speed and economic speed, and the weak link of the system is analyzed.The research methods and results have guiding significance for the dynamic characteristic design of vehicle exhaust system.