随机侧风下高速列车在桥塔环境中气动载荷的时域与频域特性研究  

Research on Time and Frequency Domain Characteristics of the Aerodynamic Load on a High-speed Train in the Bridge Tower Environment Under Random Crosswinds

作　　者：杜礼明[1] 葛文帅 章芝霖 DU Liming;GE Wenshuai;ZHANG Zhilin(College of Locomotive and Rolling Stock Engineering,Dalian Jiaotong University,Dalian 116028,China)

机构地区：[1]大连交通大学机车车辆工程学院,辽宁大连116028

出　　处：《铁道车辆》2024年第1期13-18,共6页Rolling Stock

摘　　要：在列车高速行驶过程中,强侧风的作用使得高速列车气动载荷急剧变化,可能会引起列车倾覆。文章对比分析了在恒定侧风和随机侧风的作用下,某型高速列车通过桥塔环境时头车所受到的气动载荷的时域特性,通过对其气动载荷进行快速傅里叶变换,得到了频谱分布特性。结果表明:在恒定侧风作用下,高速列车的气动载荷变化平缓,波动较随机侧风明显平缓;而在随机侧风的作用下,随着基频风速增大,气动载荷的极值大小基本不变,但极值点数目增加,这表明随机侧风模型和基频风速增加,对列车气动载荷变化影响显著。气动载荷功率谱密度集中出现在0~5 Hz范围内,最大值对应频率集中在0~1 Hz范围内,表明由侧风导致的列车所受非定常气动载荷的频率较低,这与列车本身的一些固有振动模态频率非常接近,易形成共振;与恒定侧风相比,随机侧风下气动载荷功率谱密度峰值更大,且随着基频风速增大而增大。When a train runs at a high speed,strong crosswinds will cause abrupt change of aerodynamic loads on the high-speed train and may cause the overturn of the train.This article compares and analyzes the time domain characteristics of aerodynamic loads on the lead unit of a certain type of high-speed train in the bridge tower environment under constant and random crosswinds and performs the fast Fourier transform on its aerodynamic load,to obtain the spectrum distribution characteristics.The result shows that under constant crosswinds,the aerodynamic load on the high-speed train changes gently and the fluctuation is obviously gentler than that under random crosswinds;while under the random crosswinds,as the basic-frequency wind speed increases,the extreme value of aerodynamic load remains basically unchanged,but the number of extreme values increases,which indicates that the increase of the random crosswind model and the basicfrequency wind speed has a significant impact on the change of aerodynamic load on the train.The power spectral density of aerodynamic load is concentrated in the range of 0~5 Hz,and the maximum corresponding frequency is concentrated in the range of 0~1 Hz,which indicates that the frequency of unsteady aerodynamic load on the train caused by crosswinds is relatively low,which is very close to some inherent vibration mode frequencies of the train itself and easy to form the resonance;compared with the constant crosswinds,the peak power spectral density of aerodynamic load under random crosswinds is larger and increases with the increase of the basic-frequency wind speed.

关 键 词：随机侧风 桥塔 气动载荷 时域 频域 

分 类 号：U271.91[机械工程—车辆工程]