横风下移动列车非定常气动力计算

CALCULATION OF THE UNSTEADY AERODYNAMIC FORCES ON MOVING TRAINS UNDER CROSSWINDS

为研究横风对移动列车非定常气动力的影响,该文介绍了两种获得移动列车脉动风速时程的模拟方法;基于准定常理论和气动权函数方法,推导了能同时考虑三个方向的湍流脉动和不同横风风向角效应的移动列车非定常气动力计算公式;通过数值算例,研究了不同参数对计算结果的影响。研究结果表明:通过气动权函数方法得到的非定常气动力会出现滤波和时间滞后效应;当考虑更多方向的湍流分量时,会获得更大的力脉动;横风风向角和侧向湍流分量会分别影响非定常力的均值和变异系数。

We investigate the effect of crosswinds on the unsteady aerodynamic forces of moving trains.Two methods are introduced to simulate the fluctuating wind velocity at the position of a moving vehicle.Using the quasi-steady theory and aerodynamic weighting function approach,a calculation formula of the unsteady forces on moving trains is established by considering the nature of different turbulent components and various wind directions.A numerical example is given to explore the effect of different parameters on the simulated results.The results show that the filtering and time-lag effects are observed in the weighting function approach.As additional wind turbulences from different directions are considered,there are greater fluctuations in the force.The mean value and coefficient of variance of the unsteady forces are affected by the various wind directions and lateral turbulences,respectively.