基于Sobol’法的轨道车辆前端吸能结构灵敏度分析

Global Sensitivity Analysis of Energy-absorbing Structure for Rail Vehicle Based on Sobol’Method

将全局灵敏度分析方法应用到轨道列车耐撞性分析当中。以轨道车辆前端吸能结构参数作为设计变量,分别以总吸能量和接触力峰值作为目标响应,采用Sobol’分析法,通过构建Kriging代理模型,计算各参数的一阶主灵敏度值、总灵敏度值和二阶交互效应灵敏度值,并进行分析,辨别对吸能性能影响较大的参数,将简化后结构与原结构的优化结果进行比较。结果表明:Kriging代理模型具有较高的精度,能满足耐撞性分析的要求;Sobol’法能很好地评价该过程的灵敏度,为优化设计提供有力参考,简化优化模型。

Global Sensitivity Analysis(GSA)is introduced into the crashworthiness analysis of the rail vehicles.Based on the parameters of energy-absorbing structures at the front end of the subway trains,which were defined as design variables,the Kriging models of total energy absorption and peak contact force using Sobol’method were established,respectively.The first-order sensitivities,the second-order interaction effect sensitivities and total sensitivities of each parameter were analyzed to determine the key parameters with remarkable influence on energy absorption performance.The comparison between optimization results before and after simplification based on sensitivity analysis indicates that the precision of Kriging model can meet the requirements of crashworthiness analysis,and Sobol’global sensitivity analysis method could evaluate the sensitivity of the process and provide effective guidance for the subsequent optimization.