汽车减振器非圆截面节流孔节流特性分析

摘要

With the dual-sleeve hydraulic shock absorber in rear suspension of a passenger car as the object, the performance analysis model of the shock absorber was built by using the combination of 1D and 3D simulations. Several physical phenomena, such as the static and viscous frictions, elastic deformation of the solid boundaries and specific leakages, were considered. The simulation methods of the non-circular throttling orifices (i.e. rectangular orifices of piston and bottom valve and valve gaps of circulation valves, compression valves etc.) in 1D model were discussed. And the effects of deformation of throttling valves on the throttling characteristics of the valve gaps were analyzed. It is shown that the simulation accuracy of using the flow-pressure characteristic obtained by 3D simulation to define the non-circular orifices is higher than that of using empirical formula. The valve gaps show different throttling characteristics with the different valve deformation. Comparison of simulation results with experimental results shows that the error of simulation results is nearly 6%at the speed of 0.05, 0.1, 0.6, and 1.0m/s, which indicates that the simulation of the non-circular orifices is correct and feasible. It also shows that the refined model of the shock absorber can accurately replicate the dynamic characteristics of the shock absorbers.%以某乘用车后悬架双筒充气式液压减振器为研究对象，采用一维和三维仿真相结合的方法建立考虑减振器摩擦力、橡胶衬套和减振器泄漏等因素的减振器性能分析模型。对减振器中存在的非圆截面节流孔在一维模型中的模拟进行探讨，同时探讨阀片变形对阀片缺口节流特性的影响。通过仿真结果与实验结果的对比可知，采用三维仿真获得的压降-体积流速定义非圆孔的方法，对减振器中非圆孔的节流特性进行研究是切实可行的，所建立的双筒充气式液压减振器精细化模型可很好地模拟减振器的动态特性。