曾广志, 李志伟, 黄莎, 等. 龙卷风环境对桥上运动列车瞬态气动特性影响[J]. 空气动力学学报, 2021, 39(5): 120−131. doi: 10.7638/kqdlxxb-2021.0140
引用本文: 曾广志, 李志伟, 黄莎, 等. 龙卷风环境对桥上运动列车瞬态气动特性影响[J]. 空气动力学学报, 2021, 39(5): 120−131. doi: 10.7638/kqdlxxb-2021.0140
ZENG G Z, LI Z W, HUANG S, et al. Transient aerodynamic characteristics of a moving train on bridge in tornado environment[J]. Acta Aerodynamica Sinica, 2021, 39(5): 120−131. doi: 10.7638/kqdlxxb-2021.0140
Citation: ZENG G Z, LI Z W, HUANG S, et al. Transient aerodynamic characteristics of a moving train on bridge in tornado environment[J]. Acta Aerodynamica Sinica, 2021, 39(5): 120−131. doi: 10.7638/kqdlxxb-2021.0140

龙卷风环境对桥上运动列车瞬态气动特性影响

Transient aerodynamic characteristics of a moving train on bridge in tornado environment

  • 摘要: 为探究桥上运动列车穿越龙卷风风场时其周围瞬态流场的流动特性,通过数值方法开展了恶劣环境下的车桥耦合气动特性研究,以保障列车的运行安全。采用三维、不可压N-S方程和工程上应用广泛的k-ε湍流模型,以及滑移网格技术,对桥上运动列车沿不同横向中心间距和不同运行速度穿越龙卷风风场时,其表面压力分布及气动载荷变化情况进行了计算分析。结果表明:1)列车的表面压力系数随列车与龙卷风中心的横向间距增加而表现出减小的趋势,且背风侧的压力系数较之迎风侧更为显著;2)随列车沿纵向方向靠近风场中心,其附近的压力分布呈现由对称分布向非对称分布的变化趋势,而随列车穿越风场并远离龙卷风风场中心时,列车周围压力表现出与之靠近风场中心时反向对称的特点;3)随着列车与风场中心纵向距离的变化,其头车的气动载荷系数均表现出了双峰趋势特征,且尾峰的峰值较之头峰更为显著,并随着列车运行速度的降低,其气动载荷系数峰值随列车与风场中心横向间距的差异愈加明显。

     

    Abstract: To investigate the flow characteristics of the transient flow field around a moving train on the bridge passing through the tornado wind field, vehicle-bridge coupling aerodynamic characteristics in a harsh environment are numerically simulated to ensure operational safety. This study uses numerical simulations based on the three-dimensional incompressible N-S equations and the k-ε turbulence model, to analyze the surface pressure distribution and aerodynamic forces of a train on the bridge under different lateral distances between the moving train and the tornado center as well as different operational speeds passing through the wind field. The results show that: 1) The surface pressure coefficient of the train shows a decreasing trend as the lateral distance from the center of the tornado increases, and such a trend is more obvious on the leeward side compared to the windward side; 2) As the train approaches the center of the tornado along the longitudinal direction, the pressure distribution around the train presents a change from the symmetrical to asymmetrical distribution. The reverse symmetry characteristics appear after the train passes through the center of the tornado and moves away from the wind field; 3) With the change of the longitudinal distance between the train and the center of the tornado, the aerodynamic load coefficients of the head carriage show bimodal features, and the tail peak is more significant than the head peak. Moreover, as the operational speed of the train decreases, the variation of peak values of aerodynamic load coefficients with the lateral spacing from the center of tornado becomes more obvious.

     

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