双筒式液压减振器阻尼力建模与灵敏度分析

摘要

为提高减振器阻尼力输出的准确性及减振器性能可靠性,定量分析双筒式液压减振器尺寸参数及其公差、油液黏度等对阻尼力的影响.根据阻尼力的产生机理,建立了减振器复原行程中复原阀开启前、后的阻尼力模型和压缩行程中压缩阀开启前、后的阻尼力模型,利用MATLAB仿真得到了其示功图和速度特性图,并通过台架性能试验进行了验证.考虑到阻尼力模型的复杂性,采用ANSYS中的Design Exploration模块,利用响应面法得到了减振器各个参数的灵敏度,并针对油液黏度、阀系开启高度等影响较大的参数,考虑其随机性,利用蒙特卡洛抽样方法得到了减振器阻尼力的分布,从而为双筒式液压减振器的设计提供了依据,为进一步研究减振器的阻尼力退化及寿命评估奠定了基础.%In order to improve the accuracy of the damping force`s output and performance reliability of the damper, the influence of size and tolerance of the double-tube hydraulic damper and the viscosity of the oil on the damping force is quantitatively analyzed.According to the generation mechanism of the damping force, the damping force model before and after the recovery valve opened in the recovery stroke and the damping force model before and after the compression valve opened in the compression stroke were established.By using the MATLAB simulation, the indicator diagram and speed characteristics diagram were obtained, and the performances were verified by bench test.The sensitivity analysis of the different parameters was done by using the Design Exploration module of ANSYS considering the complexity of model.Based on the randomness of the oil viscosity, the opening degree of the recovery (compression) valve which has more influence on the damping force, the prior distribution of the damping force was calculated by using Monte Carlo method.The results show that the damping force is distributed normally, and the method provides a basis for the design of double-tube hydraulic damper.