长大平车车体钢结构模态频率优化方法  

Modal Frequency Optimization Method for Long Flat Vehicle Body Steel Structure

作　　者：李晓峰[1] 周世新 LI Xiaofeng;ZHOU Shixin(School of Locomotive and Rolling Stock Engineering,Dalian Jiaotong University,Dalian 116021 Liaoning,China)

机构地区：[1]大连交通大学机车车辆工程学院,辽宁大连116021

出　　处：《铁道机车车辆》2024年第5期80-87,共8页Railway Locomotive & Car

基　　金：国家重点研发计划(2017YFB1201303)。

摘　　要：为解决长大平车低阶模态频率数值较小的问题,基于灵敏度分析法,依托优化设计数学模型,开展提高低阶振动频率数值的研究。首先建立长大平车有限元模型,计算车体钢结构状态下无约束模态。然后使用灵敏度分析方法计算得到一阶垂向弯曲频率与车体质量相对于车体装载加固装置中各构件厚度灵敏度。而后基于由单一响应灵敏度关联获得的相对灵敏度,结合不同灵敏度阈值对车体结构优化代价和优化效果影响,最终确定对以装载加固装置中梁、端梁等17个构件厚度为设计变量,一阶垂向弯曲频率最大值为优化目标进行车体结构优化。结果表明:优化后车体一阶垂向弯曲频率提高4.51%,车体质量降低5.34%,车体强度无明显变化。In order to solve low-value problem of modal frequency for the long flat vehicle,research on improving the low-order vibration frequency value is carried out based on the sensitivity analysis method and relying on the optimal design mathematical model.Firstly,the finite element model of the long flat vehicle is established,and the unconstrained mode of the vehicle body under the state of the steel structure is calculated.Then the sensitivity analysis method is used to calculate the first-order sag frequency and the sensitivity of the vehicle body mass to the thickness of each component in the vehicle body loading reinforcement device.Then,based on the relative sensitivity obtained from a single response sensitivity correlation,combined with the influence of different sensitivity thresholds on the optimization cost and optimization effect of the vehicle body structure,it is finally determined that the thickness of the 17 components such as the middle beam and the end beam of the loading reinforcement device is used as the design variable.The maximum value of the vertical bending vibration frequency is the optimization target to optimize the vehicle body structure.The results show that after optimization,the first-order sag frequency of the vehicle body is increased by 4.51%,the body mass is reduced by 5.34%,and the vehicle body strength has no significant change.

关 键 词：长大平车 模态分析 灵敏度分析 灵敏度阈值 尺寸优化 

分 类 号：U272.65[机械工程—车辆工程]