轨道随机不平顺的谱表示-随机函数模拟及应用

Simulation and Application of Random Track Irregularity by Spectral Representation and Stochastic Function

以轨道随机不平顺时域样本数值模拟方法为研究对象,采用谱表示-随机函数法分别由2个随机变量模拟生成轨道高低、水平、方向、轨距不平顺,并利用基于广义概率密度演化理论的非线性车辆-轨道耦合动力学随机分析模型,进行耦合动力系统随机振动分析。结果表明:利用谱表示-随机函数法模拟所得轨道不平顺时域样本集的均值、标准差、轨道谱、各频点谱概率分布均与原轨道谱一致;与三角级数法、傅里叶逆变化法相比,模拟生成轨道不平顺幅值范围误差在5.51%以内;该方法减少了模拟轨道不平顺时域样本所需的随机变量数,提高了基于概率密度演化理论的非线性车辆-轨道耦合系统随机振动计算效率,为随机振动分析中轨道随机不平顺模拟提供了新思路。

In this paper,based on the time-domain sample numerical simulation method of random track irregularities,the spectral representation and stochastic function method was used to simulate the track vertical profile,cross-level,alignment and gauge irregularities from two random variables.The coupled system random vibration was studied by using the nonlinear vehicle-track coupling dynamic model based on the generalized probability density evolution theory.The results show that the track irregularity time-domain sample set mean value,standard deviation,track spectrum,probability distribution of track spectrum at each frequency point are basically consistent with the original track spectrum.Compared with the trigonometric series method and Fourier inversion method,the range error of simulated track irregularity set amplitude is less than 5.51%.This method reduces the number of random variables required to simulate track irregularity samples,improves the efficiency of analysing the nonlinear vehicle-track coupling system based on probability density evolution theory,and provides a new idea for the random track irregularity simulation in the stochastic vibration study.