摘要
通过三维大涡模拟(LES)数值计算方法,对横风中不同行使工况下高速列车的非定常空气动力特性进行研究。计算得到各工况下高速列车车体所受非定常空气动力的时域特性、频域特性、脉动特性,以及列车周围非定常流动结构。分析结果表明,横风中高速列车所受空气动力存在明显的非定常性。从各工况高速列车所受空气动力脉动的均方根值来看,各节车的非定常现象基本随着合成风向角的增加而增大。在高速列车所受非定常空气动力的频域特性方面,其峰值频率集中在斯托劳哈尔数0.05~0.2范围内,这一范围对应实车情况的频率为0.5 Hz^2 Hz,这与高速列车系统本身存在的一些固有振动频率接近,存在由横风引起高速列车系统共振、降低高速列车行驶安全性乃至引发高速列车脱轨倾覆的可能性。
The unsteady aerodynamic characteristics of a high speed train in different operating conditions under cross wind were studied numerically by the 3D large eddy simulation method.The characteristics of the unsteady forces acting on the train for different operating conditions were presented from the numerical results,which included the characteristics of the time domain,the frequency domain,and the pulsation.In addition,the flow structures for different conditions were also shown.The numerical results indicate that the aerodynamic forces on the train have strong unsteady characteristics.From the values of the mean square root of the unsteady aerodynamic forces in different conditions,the unsteady levels of the aerodynamic forces were raising with the increase of the yawing angle of the wind for majority conditions.The unsteady aerodynamic forces have obvious peaks in their frequency domain.These peaks＇ Strouhal number lies mainly in the range between 0.05~0.2,which is about 0.5~2 Hz for a real high speed train operating condition,and this frequency range is very close to the modal frequency range of a real high speed train.It is thus possible that the train as a dynamical system will be resonated by the unsteady aerodynamic forces due to the cross wind and the resonance could lead to reducing of the operating safety of the train,even lead to the overturning of the train.
出处
《铁道学报》
EI
CAS
CSCD
北大核心
2010年第2期18-23,共6页
Journal of the China Railway Society
关键词
高速列车
横风
倾覆
非定常空气动力
high speed train
cross wind
overturning
unsteady aerodynamic force
