Abstract:In order to analyze the dynamic characteristics of the exhaust system in the whole speed range (0-6000r/min), a dynamic characteristics test-bed was designed and a finite element numerical model of the exhaust system was established. Through simulation and experiment, the natural frequency and mode shape of exhaust system in the corresponding speed and frequency range are obtained. The natural frequency error of simulation and experiment results is less than 10%, and the vibration mode is basically the same, which shows that the finite element model of dynamic characteristic analysis is accurate. Then, the finite element numerical model including the power train is established to calculate the dynamic force of the power train from starting to idling and stable operation, and the exhaust system to the vehicle body. The results show that after the power train starts to idle, the dynamic force transmitted by the rubber hanger to the body is less than 5N, and the natural frequency of the system is staggered with the power train excitation frequency to avoid resonance and meet the design requirements.