减振器节流阀片区段均布压力下应力解析算法及其应用

Analytical algorithm for the stress of damper throttle-slices and its application under interval uniformly distributed pressure

农用车辆驾驶室减振器节流阀片应力特性分析及相关问题研究普遍依赖于有限元法,尚缺少有效的解析算法,给工程应用带来诸多不便。针对该问题,该研究建立驾驶室减振器节流阀片区段受压力学模型,推导基于阀片应力影响系数的周向、径向及复合应力解析表达式,进而提出一种简洁实用的减振器节流阀片区段均布压力作用下应力特性解析算法,该算法确切计及了区段压力、阀片片数、各片厚度、阀口半径、上垫片半径及下垫片半径等参数。实例计算分析和有限元仿真对比结果显示在减振器工作压力下,各片阀片不同半径位置处周向应力、径向应力及复合应力解析值与仿真值的相对偏差均在1.5%以内,表明了所提算法的正确性和可靠性。在此基础上,建立了基于该解析算法的驾驶室减振器叠加节流阀片应力快速校核方法、节流阀片厚度拆分设计方法及优化设计准则,并进行实例设计和减振器台架试验,结果显示所设计减振器与原减振器阻尼力最大相对偏差仅为4.6%,且100.0万次以上仍可正常工作。该算法避免了有限元法的诸多局限,可有效应用于揭示减振器叠加节流阀片结构参数与应力内在物理联系、结构参数对应力影响规律,为相关工程技术人员提供了更为实用、便捷的有效工具。

Damper throttle-slices of the cab relies generally on the Finite Element(FE)method for the stress characteristic analysis.It is still a lack of an analytical algorithm for the engineering application.This study aims to construct the analytical algorithm,the program interface of the stress characteristic analysis,the verification,and the thickness split design of throttle-slices of the cab for agricultural vehicles.The stress analytical formula was deduced using the stress influence coefficient.Then,a simple and practical analytical algorithm was proposed for the stress characteristic of the damper throttle-slices under the interval uniformly distributed pressure for cabs.The parameters were considered,such as the interval uniformly distributed pressure,the number of pieces,the thickness,the valve port radius,the upper gasket radius,and the lower gasket radius.The FE simulation and the theoretical analysis show that the analytical stress values of each slice at different radius positions under the working pressure were close to the simulation values for the circumferential stress,radial stress,and composite stress.Moreover,the relative deviations were all within 1.5%.The stress influence coefficient was obtained under the section uniform pressure.There were the same radial,circumferential,and composite stress influence coefficients of each slice,particularly independent of the slice thickness and section uniform pressure.Among them,the maximum influence coefficient occurred at the radius rd of the lower gasket.The stress analytical formulae revealed that the greater the thickness of each slice was,the greater the radial,circumferential,and composite stress values were.The analytical algorithm was used to establish the rapid stress check,the split design of the thickness,and the optimization design.The effectiveness of the analytical algorithm was further verified by the case study and the damper test.The throttle-slice fracture occurred before the number of tests reached 50000 times in the damper equipped with the original single slice.The damper that was assembled with the designed superimposed throttle-slices worked normally after more than 1.0 million times.Moreover,there was no slice fracture,indicating the effective thickness split of superposition slices in the damper.The algorithm effectively avoided many FEM limitations.There was the internal physical relationship between the structural parameters and the stress of the superimposed throttle-slices,the influence of the structural parameters on the stress,the rapid check of the stress intensity of the throttle-slices,and the disassembly design of the throttle-slices.The finding can provide a more practical and convenient effective tool for the relevant engineering and technical personnel.