【摘要】 轨道不平顺是轮轨系统的主要激扰源,在机车车辆随机振动响应、列车动态模拟等领域应用广泛。针对三角级数法模拟轨道不平顺信号的不足,在其基础上根据小波模拟信号的基本原理,提出了一种以频带能量为标准的小波模拟方法,推导了其模拟公式。分别采用三角级数法和Daubechies(db6)小波进行轨道不平顺信号的模拟,并将其功率谱值分别与给定的目标功率谱值相比较,且对比分析了不同小波和不同分解层数对模拟结果的影响。研究结果表明:基于小波理论的模拟方法得到的轨道不平顺信号功率谱曲线,是一条连续的斜线,能与给定的目标功率谱值基本吻合,具有带宽随机波的谱特征,能够表现轨道不平顺信号的基本特性。小波函数的选取对模拟结果有一定的影响,工程应用时应优先考虑消失矩阶数高的小波函数。更多还原

【Abstract】 The track irregularity is the main excitation source to the wheeltrack system,widely used in rolling stock random vibration response,train dynamic simulation and other fields. Based on the shortage of simulation of track irregularity signal by using trigonometric series,according to the fundamental theory of wavelet simulation single,one wavelet simulation method on the basis of frequency band energy is put forward with the relevant formulas derived. The simulation of the track irregularity signal is performed by adopting trigonometric series and Daubechies wavelet respectively.Their power spectral values are compared with target power spectral value. And the impact of different wavelet and the different decomposition levels on the simulated result are compared and analyzed. The research result shows that the power spectrum curve of track irregularity signal by using wavelet simulation is a seriate oblique line basically agrees well with target power spectrum value with the spectrum signature of bandwidth random wave,presenting the basic characteristics of track irregularity signal. The selection of the wavelet function has some effects on the result of simulation,the wavelet function with higher vanishing moments shall be given priority the engineering application.更多还原