列车风荷载是铁路邻近结构设计和确定相关建筑限界时必须考虑的问题。雨棚是一种典型铁路邻近结构,高速列车经过时雨棚表面受到的列车气动力不可忽视。基于计算流体力学软件Fluent,结合k-ε两方程湍流模型,采用滑移网格技术,对雨棚周围的三维非定常可压缩流场进行数值模拟,分析雨棚表面风压分布规律及雨棚开口宽度、外形对其表面风压的影响。结果表明:高速列车经过时雨棚表面受到瞬时脉冲荷载作用;雨棚开口宽度0~8m时列车风压受到明显影响,随着雨棚开口宽度增加结构表面风压极值逐渐变小,开口宽度对列车风压影响范围为正线两侧10m;雨棚外形对列车风压有明显影响,拱形雨棚表面风压极值最小,雨棚外形对列车风压影响范围为正线两侧10m。
Train-induced aerodynamic loads on track adjacent structures are an issue that must be considered during the design of these structures and the determination of their clearance.As canopy is a typical track adjacent structure,train-induced pressure and its aerodynamic effects on canopy structure cannot be ignored.Based on the CFD software Fluent,the sliding mesh technology combined with the k-εtwo-equation turbulence model was adopted to simulate the three-dimensional unsteady compressible flows around a canopy structure and to study the canopy surface wind pressure distribution and the influence of canopy structure opening width and shape on the surface wind pressure.Results showed that the passage of high-speed train resulted in transient forces on the canopy structure.The train-induced wind pressure was significantly affected when the canopy opening width ranged from 0mto 8m.The pressure of canopy structure surface decreased with larger opening width.The sphere of the influence of the opening width on train-induced wind pressure is within 10 mof both sides of the center line.The shape of canopy structure had significant effect on the train-induced wind pressure.The surface wind pressure of arched canopy was minimum.The sphere of the influence of canopy shape on traininduced wind pressure was within 10 mof both sides of the center line.