具有烟囱效应的某铁路隧道紧急出口防烟系统设计

Design of Smoke Control System for the Emergency Exit of Railway Tunnels with Chimney Effect

为解决某铁路隧道长大上坡式紧急出口在冬季防护门断面处无法产生防烟正压风速的问题,对该隧道长度、坡度、内部温度、环境温度等进行分析,认为该紧急出口存在较为严重的烟囱效应。建立计算机仿真模型,分别采用增加防烟射流风机、增设挡风墙和改建避难所3种解决方案,模拟在夏季、冬季、火灾工况的防烟效果,并对结果进行分析。证实了改建为封闭式避难所的方案可以确保紧急出口防护门断面处产生稳定的正压风速,并对避难所疏散门设置、硬件补强措施和疏散注意要点等提出建议。

In order to solve the problem that railway tunnels with long uphill emergency exit cannot produce positive pressure ventilation to stop the spread of smoke in the section of emergency exit in winter,the author analyzed the tunnel length,slope,internal temperature and environmental temperature,and concluded that there is a serious chimney effect at the emergency exit.To solve this problem,the author establishes a computer simulation model,and adopts three solutions:adding jet fan,adding wind break wall and rebuilding a fully enclosed shelter.It is proved that the scheme of rebuilding a closed shelter can ensure the stable positive pressure ventilation at the emergency exit.At last,some suggestions are put forward,including installing an evacuation door,hardware reinforcement and evacuation tips.