基于有限单元法铰接式车辆后车架优化分析

Optimization Analysis of the Rear Frame of Articulated Vehicle Based on Finite Element Method

铰接式车辆后车体受力情况复杂,设计中需要重点分析。根据整车的受力情况,对后车体和后车架的受力情况进行分析,获取不同工况下的受力特点;基于有限单元法搭建后车体的强度分析模型,选取水平插入工况、后轮离地工况和前轮离地等三种典型工况进行分析,获取各工况下应力的极值点;基于分析结果对后车架进行结构和工艺优化设计;采用应变花对优化后的实车进行测试,获取测点的最大值与仿真结果进行对比,结果可知:后车体各部分的强度均可以满足要求,但局部位置存在应力集中的现象,其中应力值较大的部位主要集中在后车体的上、下铰接板处及轴承安装处;采用应变花对优化后实车的应力值进行测试,测点的最大值分别为56.7MPa、109.45MPa,与仿真值之间的误差小于6%,同时均小于优化前的数值,表明优化方案是可行的,优化设计结果是可靠的。

The force of the rear body of the articulated vehicle is complicated and needs to be analyzed in the design.According to the force of the whole vehicle,the force of the rear and rear frames was analyzed to obtain the force characteristics under different working conditions.Based on the finite element method,the strength analysis model of the rear car body was built,and three typical working conditions,such as horizontal insertion working condition,rear wheel grounding condition and front wheel grounding,were selected for analysis,and the extreme points of stress under each working condition are obtained.Based on the analysis results,the rear frame was optimized for structure and process design.The strained flower was used to test the optimized real vehicle,and the maximum value of the measured point is compared with the simulation result.The strained flower was used to test the optimized real vehicle,obtained the maximum value of the measurement point and compare it with the simulation result.The results show that the strength of each part of the rear body can meet the requirements,but there is a phenomenon of stress concentration at the local position.The part with large stress value is mainly concentrated on the upper and lower hinge plates of the rear body and the bearing installation.The strain flower is used to test the stress value of the optimized vehicle.The maximum values of the measuring points are 56.7MPa and 109.45MPa respectively,and the error between the simulated values is less than 6%,and both are smaller than the values before optimization,indicating that the optimization scheme is feasible and the optimization design results are reliable.