铁路隧道竖井设置对隧道活塞风的影响

The influence of the setting of the railway tunnel shaft on the piston wind in the tunnel

隧道活塞风对于隧道内通风环境起到极其大的作用,竖井直接影响隧道内运营通风环境。基于Fluent软件,选用RNG k-ε湍流模型,利用软件二次开发UDF和动网格技术,模拟分析列车通过竖井时隧道活塞风分布规律。研究表明:列车头部形成增压区域,车尾部形成数个尾涡区;列车环隙空间近列车壁面气流速度较大,近隧道壁面气流速度较小,纵向环隙气流的速度从车头到车尾逐渐减小;竖井内流体的速度场受活塞风影响较大,对环隙空间流场的后段作用显著,分流作用使得剪切力的增压减小。

The piston wind of tunnel plays an extremely important role in the ventilation environment of tunnel.The influence of shaft on the piston wind of tunnel will directly affect the operation ventilation environment of tunnel.Based on Fluent software,RNG k-εturbulence model is selected,UDF and dynamic grid technology are developed by using the software to simulate and analyze the distribution law of tunnel piston wind when the train passes through the shaft.The results show that:the pressurization area is formed at the head of the train,and several wake vortices are formed at the tail of the train;the air flow velocity near the train wall is larger in the annular space of the train,and smaller near the tunnel wall,and the air flow velocity in the longitudinal annular space is gradually reduced from the head to the tail of the train;the velocity field of the fluid in the shaft is greatly affected by the piston wind,which has a significant effect on the back section of the annular space flow field,and the diversion effect makes the increasing pressure of shear force decrease.