随机风作用下高速列车动力学参数的可靠性优化设计

建立随机风作用下高速列车动力学参数的可靠性优化设计方法．首先考虑自然风的脉动特性，采用Cooper理论和谐波叠加法模拟随车移动点的脉动风速，给出随机风作用下高速列车非定常气动载荷的计算方法．然后建立高速列车车辆系统动力学模型，计算高速列车的运行安全性，并基于可靠性理论，给出随机风作用下高速列车失效概率的计算方法．在此基础上，以高速列车动力学参数为优化设计变量，以失效概率和轮轴横向力为优化目标，采用多目标遗传算法NSGA—II进行动力学参数的自动寻优，建立随机风作用下高速列车动力学参数的可靠性优化设计模型．经可靠性优化计算，高速列车的失效概率由原始的0．4884降低为0．1406，轮轴横向力由原始的45．13kN降低为43．01kN．通过优化高速列车动力学参数可以显著改善随机风作用下高速列车的运行安全性．

Reliability optimization design of the kinetic parameters of high-speed trains under stochastic winds

The reliability optimization design method under stochastic winds was established. First, due to the fluctuating characteristic of natural winds, the fluctuating winds of a moving point shifting with high-speed trains were simulated based on Cooper theory and harmonic superposition method, and an algorithm was proposed to calculate the unsteady aerodynamic loads of high-speed trains under stochastic crosswinds. Then the multi-body system dynamics model of a high-speed train was established to calculate the operation safety of high-speed trains, and the computational formula of the probability of failure of high-speed trains under stochastic winds was further shown. On this basis, the multi-objective genetic algorithm NSGA-II was used for the automatic optimization, then the reliability optimization design model of kinetic parameters of high-speed trains was established. In the model, the kinetic parameters were taken as the optimization variables, and the probability of failure and wheelset lateral force were taken as optimization objectives. After optimization, the probability of failure was reduced from 0.4884 to 0.1406, and the wheelset lateral force was reduced from 45.13kN to 43.01kN. The operation safety of high-speed trains under stochastic winds was significantly improved by optimizing the kinetic parameters.