线间距对时速600公里级高速磁浮列车明线交会气动性能的影响

Effect of line space on aerodynamic performance of two high-speed maglev trains passing by each other at the speed of 600 km/h in open air

高速磁浮列车设计速度高达600 km/h,明线交会时压力波幅值激增,容易导致列车结构疲劳损伤。作为影响高速列车明线交会气动特性的关键参数,线间距是研究重点之一。本文采用计算流体力学数值仿真方法和网格滑移技术,模拟了高速磁浮列车在线间距5.1 m、5.4 m、5.6 m的线路上明线交会时的气动特性,对比分析了高速磁浮列车表面压力分布及列车气动力/力矩的变化规律。结果表明:明线交会时,列车气动升力、侧向力和倾覆力矩随着线间距的增加明显降低;列车表面测点压力最大值、最小值的绝对值以及最大压力幅值随线间距增加近似呈线性关系降低;线间距5.1 m时,高速磁浮列车表面最大压力幅值为5379 Pa,小于车体承载极限±6000 Pa,满足600 km/h交会时对气动特性的要求。

The designed speed of high-speed maglev trains in China is as high as 600 km/h,and the intersection pressure amplitude increases sharply when two maglev trains passing by each other in open air at this speed,which can cause some damage to the train structures.Increasing the line space between two tracks is one of the key approaches to alleviate the intersection pressure wave induced by two trains passing by each other.To better understand the effect of the line space on the intersection pressure wave,the aerodynamic performance was studied using the computational fluid dynamic(CFD)method together with the sliding mesh technology,and the pressure distribution,aerodynamic force and momentum of the train during the intersection process were analyzed and compared for three different line spaces,i.e.5.1 m,5.4 m and 5.6 m.The results show that the lift force,side force and the overturning moment decrease obviously with the increase of the line space.The maximum pressure,the absolute value of the minimum pressure and the maximum peak-peak pressure at the measurement points on the train surface all decrease linearly with the increase of the line space.For the line space of 5.1 m,the maximum intersection pressure amplitude is 5379 Pa,lower than the load limit of the train,i.e.±6000 Pa,which meets the aerodynamic performance requirement for two trains passing by each other in open air at the speed of 600 km/h.