关键词: 车辆工程；动力组；轴箱弹簧；二次开发；精细化建模；接触应力

Abstract: In response to the problem of insufficient stiffness and service life caused by the contact between the working ring and the support ring of EMU axle box spring, as well as the disadvantage of using traditional integrated scanning modeling difficultly to achieve the flat and tight features of the two end support rings, a three-stage modeling method of “lower support ring-upper support ring-working ring” was proposed according to the topological relationship of the geometric structure of the spring. The Python secondary development module of the finite element software ABAQUS was used to establish a refined finite element model of the axle box spring, thereby improving the accuracy and parameterization of the model. Considering the influence of the contact effect between the working ring and the support ring, a simulation analysis of spring characteristics was carried out from the aspects such as contact area, stiffness and stress. The influence rule of the contact relation on the characteristics of the spring was clarified, and the accuracy of the simulation results was verified by experiments. The analysis results show that there is a phenomenon of warping in the middle section of the contact line between the working ring and the support ring. As the load increases, the contact area increases exponentially, and the stiffness also exhibits a significant nonlinear increasing characteristic. The stiffness under compressive load is 17.1% higher than that without contact. The contact relation has greater influence on the shear stress of the working rig near the support ring, while it has less influence on the middle part of the working ring. The maximum error between simulation value and theoretical value is 3.91%. The stiffness and inner shear stress simulated and analyzed by parameterized finite element model both have errors of less than 5% compared to the values tested by experiments, which indicates that the proposed modeling method is feasible and can provide reference for improving the design quality and service safety of EMU axle box spring.

Key words: vehicle engineering; EMU; axle box spring; secondary development; refine modelling; contact stress