125型发动机配气机构的噪声分析

为了研究发动机配气机构的噪声机理及其影响因素,进行了某125型发动机配气机构的噪声分离实验,实验结果揭示出其主要噪声由摇臂与气门杆敲击、气门落座撞击产生.通过进一步对配气机构进行运动学和动力学仿真模型的建立与计算,分析出配气机构摇臂敲击力和气门落座加速度的产生主要与配气机构的凸轮缓冲段升程、凸轮缓冲段包角以及凸轮缓冲段加速段系数等参数有关,合理的选择凸轮参数,有利于降低配气机构摇臂敲击力和气门落座加速度,从而降低配气机构的噪声和提高配气机构的平稳性.

Analysis on Valve Train Noise of Engine

To research the mechanical and influence factors of noise of valve train of engine, noise-distinguishing test is taken with one certain 125 mL engine valve train. The result reveals that the valve train noise mainly results from impacting between rocker and valve stick, impacting of valve seating. With the way of model set up and simulating calculation of kinematics and dynamic of valve train, the influence factor of rocker impact force and valve seating acceleration of valve train is studied, which reveals that the acceleration of valve and impacting force between rocker and valve stick are mainly relied on cam buffer segment lift, cam buffer segment wrap angle and coefficient of accelerating segment of cam buffer segment. Choosing these parameters reasonably is helpful to decrease the acceleration of valve and impacting force between rocker and valve stick, and then reduce the noise of valve train.