基于平台力波动的压溃管结构参数优化设计

Structural parameter optimization design of crushed pipe based on platform force fluctuation

在列车碰撞时,车钩缓冲装置是最先开始发生变形的部分,其能量吸收特性、压溃平稳性会影响后续列车碰撞的动态行为特性。为提高车钩缓冲装置在碰撞过程中压溃的平稳性,采用基于模型的多目标遗传算法的优化方法,研究车钩压溃管吸能结构碰撞力学参数的最优配置。通过建立车钩压溃管仿真模型,分析比对仿真模型与试验测试的力学曲线,采用样本方差S2体现平台力波动,分析压溃管厚度T,加压管锥角α和加压管外半径r对比吸能(Sea)、平台力(Favg)和平台力波动(S2)的影响。将Sea,|Favg-1200|作为评价指标,S2作为约束,基于试验设计采用径向基函数法建立T,α和r关于Sea和|Favg-1200|的响应面模型,并基于模型采用多目标遗传算法对车钩压溃管结构的力学参数进行多目标优化,通过多目标优化的帕累托前沿得到了车钩压溃管的最优参数配置。研究结果表明:在所有的设计变量中,加压管外半径r对Sea的影响最大,压溃管厚度T对Favg影响最大,加压管外半径r对S2影响最大。除加压管外半径r对S2是负相关的关系,其余变量对Sea,Favg和S2都是正相关的关系。在最优参数配置下Sea提高了12.16%,Favg提高了8.35%,S2下降了58.47%,吸能量提高了6.34%。优化后的力学参数配置方案提高了车钩的吸能量,降低了压溃管平台力的波动,提高了车钩压溃管在碰撞过程中压溃的平稳性。

In the case of train collision,the coupler buffer device is the initial component subjected to deformation.The energy absorption characteristics and crushing stationarity of this device would affect the dynamic characteristics of the subsequent train collisions.To improve the crash stability of coupler buffer device in the collision process,the model-based multi-objective genetic algorithm optimization method was used to study the optimal configuration of collision mechanical parameters of coupler crash tube energy absorbing structure.By establishing the simulation model of the coupler crushing tube,the mechanical curves of the simulation model and the test were analyzed and compared.The sample variance S2 was used to reflect the platform force fluctuation.The influence of the thickness of the crushing tube T,the cone Angleαof the pressurized tube and the outer radius r of the pressurized tube on energy absorption(Sea),platform force(Favg)and platform force fluctuation(S2)was analyzed.By using Sea,|Favg-1200|as evaluation index,S2 as constraints,based on the experimental design,and by using radial basis function method,the T,alpha and r on the Sea and|Favg-1200|of the response surface model were established.The multi-objective genetic algorithm was adopted based on the model of coupling crushing multi-objective optimization for the mechanics parameters of the tube structure.The optimal parameter configuration of coupler crushing tube was obtained through the Pareto front of multi-objective optimization.The results show that,among all the design variables,the outer radius r of the pressurized tube has the greatest influence on Sea,while the thickness of the crushed tube T has the greatest influence on Favg.Additionally,the outer radius r of the pressurized tube has the greatest influence on S2.Except the outer radius r of the pressurized tube has a negative correlation with S2,the other variables have a positive correlation with Sea,Favg and S2.Under the optimal parameter configuration,Sea increased by 12.16%,Favg increased by 8.35%,S2 decreased by 58.47%,and energy absorption increased by 6.34%.The optimized configuration scheme of mechanical parameters can improve the energy absorption of coupler,reduce the fluctuation of crushing tube platform force,and improve the stability of crushing tube during collision.