高速铁路隧道缓冲结构的气动作用分析

为了减轻高速列车进出隧道时引起的洞口压力波效应,常在隧道入口加建缓冲结构.采用计算流体力学数值分析的方法,仿真计算了高速铁路隧道入口缓冲结构参数对列车以350 km/h进入隧道时的气动作用,分析了过渡段长度、缓冲段长度、缓冲结构开孔率、缓冲结构入口形式对隧道口内气体压力的影响和缓冲结构对隧道内会车压力波的影响.计算结果表明:过渡段长度和缓冲结构入口形式对隧道内气动影响很小,其他参数一定时缓冲段长度存在一最优值；缓冲结构上开孔有助于减小气体压力升高率,缓冲结构的存在有助于降低隧道内会车压力波峰值.

Aerodynamic Analysis on Entrance Hood of High-Speed Railway Tunnels

In order to reduce pressure pulse effects produced from train running into tunnels,an entrance hood is often built on high-speed railway tunnel entrance.Numerical calculations were conducted to study the effects of structural parameters of a tunnel entrance hood,such as the entrance shape,the lengths of whole entrance hood and the transition section in it,and side wall opening areas on air pressure peaks as a high-speed train enters the tunnel at 350 km/h.The calculation results show that the entrance shape,the length of transition section in entrance hood has a little effect on pressure peaks;the length of entrance hood has a optimal value as other structure fixed;increasing opening areas on the side wall reduces the rate of pressure change,but increases pressure peaks.If two trains meet in the middle of a tunnel,the presence of an entrance hood reduces the pressure peaks.