柴油机配气机构动力学特性的仿真与试验

摘要

通过理论计算和试验进行了柴油机配气机构运动学与动力学分析研究,基于多体系统动力学理论,对配气系统动态特性进行了仿真和评价,构建了配气机构动态测试系统,进行了多参数同步测量试验.仿真模拟与试验测量结果表明:气门升程曲线连续光滑,最大气门落座速度小于许用落座速度,但落座瞬间气门加速度波动幅值较大,高速时气门落座有反跳现象,正常工作状态下气门间隙为动态变化间隙,计算和试验得到的气门运动曲线变化规律基本吻合,为配气机构的性能评价和优化设计提供有价值的参考依据.%Through the theoretical calculations and actual experiment, the kinematics and dynamics of valve train for diesel engine were analyzed and researched. Based on the theory of multi-body dynamics, the simulation and evaluation of valve train dynamic characteristics were carried out. The dynamic measurement system for valve train was established and multi-parameter simultaneous measurement experiment was carried out. The results show that the curve of valve lift is continuous and smooth.The maximum seating speed of valve is less than the allowable value, but the fluctuation of valve acceleration in the seating moment is worse. At high speed, there is a slight mechanism separation when the valve is seating. Under normal conditions, the valve clearance is dynamically changing. The simulation can be in agreement with the experiment on the whole, which provides a theoretical approach for the evaluation and optimization of valve train.