双筒液力减振器节流特性试验和仿真研究

摘要

In order to understand the throttling characteristics and the damping force abnormal fluctuations,tests and simulations were carried out on the course of pressure change and the force process acting on valve disc of a hydraulic shock absorber.Setting sub-cycle can reduce the amount of calculation,however,it will cause the pressure's unreal fluctuations.After fitting,the simulated curve of pressure vs velocity with sub-cycle setting can represent the velocity characteristics of damping force.For the 118 shock absorber,the throttle orifice decides the throttling characteristics before the valve opens; and the gap between valve disc and piston decides the throttling characteristics after the valve opens.Three obvious layers appear in the stress distribution of the valve disc,so the uniform distribution hypothesis isn't appropriate.The results show that,the change of contact form between valve disc and its saddle is one of the causes which induce the damping force abnormal fluctuations.%为了解减振器的节流特性及阻尼力异常波动的原因,试验和仿真研究了减振器液压变化历程和阀片受力过程.设置子循环能减少计算量,同时会造成液压剧烈波动的假象.经拟合处理,设置子循环的液压速度过程曲线能表示阻尼力速度特性.开阀前,118减振器的节流由常通孔决定；开阀后由阀片与活塞间的缝隙决定.阀片的应力分布明显分为3层,不能认为阀片全面积受均匀分布的液压作用.结果表明:阀片与弹簧座接触方式的转变是造成异常波动的原因.