侧风下钢桁梁对移动高速列车气动特性影响的风洞试验  

Wind Tunnel Test of the Aerodynamic Characteristics of a High-speed Train Running on a Steel Truss Bridge Under Crosswind

作　　者：王铭[1] 李小珍[1] 沙海庆 肖军[1,2] WANG Ming;LI Xiao-zhen;SHA Hai-qing;XIAO Jun(Department of Bridge Engineering,Southwest Jiaotong University,Chengdu 610031,Sichuan,China;School of Civil Engineering,Chongqing Jiaotong University,Chongqing 400074,China)

机构地区：[1]西南交通大学桥梁工程系 [2]重庆交通大学土木工程学院

出　　处：《中国公路学报》2018年第7期84-91,共8页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(U1434205;51708465);国家重点基础研究发展计划("九七三"计划)项目(2013CB036301)

摘　　要：为探究侧风下钢桁梁结构内部移动高速列车的气动特性,采用研制的桥上移动列车风洞试验测试系统,对侧风下移动列车的气动力进行测试。以沪通长江大桥为工程背景,设计缩尺比为1∶30的钢桁梁和CRH3列车模型,试验系统采用伺服电机驱动,可以实现列车模型的双向加减速,试验模型最大运行速度为15m·s-1,有效采集时间为0.7s;列车模型气动力采用Mini40无线测力天平进行实时采集。采用该试验系统分别对静止列车模型和移动列车模型进行各级风速和车速下的气动力测试。结果表明:采用静止列车模型和移动列车模型模拟得到的列车模型气动力系数有所不同,其中侧向阻力系数和升力系数的差异较为明显;钢桁梁结构对移动列车具有明显的遮蔽效应,列车模型由无桥区进入有桥区时,列车各项气动力系数会发生明显减小,且变化值随着偏航角的增大而增大;对处于钢桁梁结构内部行驶的高速移动列车而言,列车行驶方向的不同会引起列车模型气动力系数的差异,这种差异会随着偏航角的增大而变得逐渐明显,当偏航角大于40°时,移动列车模型在前行方向的侧向阻力系数要小于其回行方向的侧向阻力系数;前行方向升力系数要明显大于回行方向升力系数;相比之下,力矩系数在不同行驶方向下的差异并不明显。In order to investigate the aerodynamic characteristics of a high-speed train running on a long-span bridge,the moving train wind tunnel test system was adopted and tests were performed to examine the aerodynamic forces of a train model under crosswind.A 1/30 scale model of the truss bridge was constructed based on the Hutong Yangtze River Bridge in addition to a CRH3 train.The train models were driven by a servo motor synchronous driving system,which can facilitate the two-way runs of the models.The maximum speed of the train model is 15 m·s-1 with an effective acquisition time of 0.7 s.It was possible to wirelessly determine the aerodynamic forces acting on the train models with the help of a Mini40 transducer.The aerodynamic characteristics of the train under the influence of different wind velocities and trainspeeds were measured for an equivalent stationary train model and a moving train model respectively.The results show that the aerodynamic coefficients of the train models varied for the stationary test and moving test.The difference of the side and lift coefficients appear to be more notable compared to the rolling coefficient.It was observed that the truss structures had an obvious shielding effect on the aerodynamic characteristics of the moving train,which can significantly reduce the aerodynamic coefficients when the train travels onto the truss bridge from an uncovered area.The reduction is substantial as the yaw angle increases.For the train moving inside the truss bridge,the aerodynamic coefficients vary for different driving directions.The variation is clearly observed with an increase of the yaw angle.For a yaw angle greater than 40°,the side coefficient of the moving train in the forward direction is smaller than that of the backward direction,while the lift coefficient in the forward direction is larger than that of the backward direction.In contrast,the difference between the rolling coefficient in the different driving directions is not completely clear.

关 键 词：桥梁工程 气动特性 风洞试验 移动列车 钢桁梁 

分 类 号：U442.59[建筑科学—桥梁与隧道工程]