汽车排气系统波纹管刚度和阻尼的测量分析

Measurement and Analysis for stiffness and damping of the Bellows in Automobile exhaust system

对不同结构的四种汽车排气系统波纹管,用静载试验和自由振动的方法,对波纹管的静动态轴向刚度、弯曲刚度和阻尼比进行了测试计算分析。结果表明,波纹管增加缠绕管和网套后,不但轴向、弯曲刚度和阻尼比得到了大幅度的提高,而且限制了波纹管的轴向和径向最大位移。波纹管刚度的增加,不但可以提高波纹管本身的固有频率,而且可以提高波纹管和汽车消声器组成系统整体的固有频率:阻尼的增大和最大位移的限制,不但有利于减小排气系统共振和非共振频域的振动强度,而且可以提高波纹管和汽车排气系统在恶劣路况下的使用寿命。

The axial stiffness,bending stiffness and damping ratio of four different structures automobile exhaust system bellows were measured and analyzed by static load test and free vibration.The results showed that the bellows with net sheath and winding pipe,not only improved the axial,bending stiffness and damping ratio,and limited bellows maximum displacement in axial and radial.Increasing the stiffness,could improve the natural frequencies of the bellows and the entire system that composed by the bellows and car muffler;increasing damping and limiting the maximum displacement,not only tended to reduce the resonance of exhaust system and vibration intensity in non-resonant frequency domain,but also improved the bellows and automotive exhaust system's life in the harsh road conditions.