甘青隧道火灾烟气扩散特征研究  

Study on the Smoke Dispersion Characteristics of the Fire in Ganqing Tunnel

作　　者：杨家伟 刘屈瑶 梁庆国[2] 曹生慧 孙纬宇 吴晓辉 周仁 YANG Jiawei;LIU Quyao;LIANG Qingguo;CAO Shenghui;SUN Weiyu;WU Xiaohui;ZHOU Ren(China Railway Erju 4 th Engineering Co.,Ltd.,Chengdu 610031,China;School of Civil Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China;Lanzhou-Xinjiang Railway Gan-Qing Co.,Ltd.,Lanzhou 730030,China)

机构地区：[1]中铁二局集团第四工程有限公司,成都610031 [2]兰州交通大学土木工程学院,兰州730070 [3]兰新铁路甘青有限公司,兰州730030

出　　处：《铁道标准设计》2025年第1期147-155,共9页Railway Standard Design

基　　金：国家自然科学基金项目(51968041);中国博士后科学基金项目(2021M693843)。

摘　　要：研究高海拔地区特长铁路隧道火灾烟气的变化规律对优化设计特长铁路隧道防灾救援具有重要的指导意义,但由于高海拔地区复杂的地理位置和使用环境,采用试验方法进行研究较为困难,相关研究较少。依托甘青隧道工程,基于Fire Dynamics Simulator(FDS)开展高海拔地区特长铁路隧道火灾场景数值模拟,通过改变隧道纵向风速大小以及纵向风作用方向,以期获得依托工程发生火灾下的致灾因素以及最佳控烟方案,并与平原地区火灾发生时的致灾因素仿真模拟结果进行对比。研究结果表明:高海拔地区火灾烟气扩散速度以及特征高度处最高温度、最高CO浓度均高于平原地区;高海拔地区隧道发生火灾时,施加纵向风较有利,且随着纵向风速增加,顺风侧烟气扩散速度加快,逆风侧逆流长度能够得到有效控制;高海拔地区特长隧道内可视度是达到危险限值最快、影响最大的致灾因素,且不受风速影响;有无纵向风作用下,隧道一侧均存在低可视度危险区;纵向风越大,烟气扩散速度越快,特征高度处温度越低,对高温烟气扩散的抑制作用越明显;本工程条件下建议加强隧道下坡段风机的设计,并应控制纵向风速≮3 m/s。The study on the change rule of fire smoke in high-altitude areas of extra-long railway tunnels has important guiding significance for the optimisation of the design of extra-long railway tunnels for disaster prevention and rescue,but due to the complex geographic location and the service e environment in high-altitude areas,it is more difficult to study using experimental methods with fewer related researches.Relying on the Ganqing Tunnel Project,the numerical simulation of fire scenarios in extra-long railway tunnels in high-altitude areas is carried out based on the Fire Dynamics Simulator(FDS).By changing the longitudinal wind speed and the direction of the longitudinal wind in the tunnels,it is hoped to obtain the causative factors of fires occurring in the relying project as well as the optimal smoke-control scheme,and to compare the results with those of the simulation of causative factors of fires occurring in the plain areas.The results of the study show that the rate of smoke dispersion and the maximum temperatures and CO concentrations at characteristic altitudes are higher at high-altitudes than in plain areas.The imposition of longitudinal winds is more advantageous in the event of a fire in a tunnel at high-altitude,and as the longitudinal wind speed increases,the downwind flue gas diffusion speed increases and the upwind backflow length can be effectively controlled.Visibility in long tunnels at high-altitudes is the fastest and most influential causal factor in reaching hazard limits,and is not affected by wind speed;low visibility hazard zone exists on one side of the tunnel either with or without longitudinal wind action.The higher the longitudinal wind,the faster the flue gas diffusion,the lower the temperature at the characteristic height and the more pronounced the inhibition of high temperature flue gas diffusion.The conditions of this project suggest that the design of the fans in the downhill section of the tunnel should be strengthened and the longitudinal wind speed should be controlled

关 键 词：高海拔地区 铁路隧道 特长隧道 烟气扩散 致灾因素 控烟方案 

分 类 号：U25[交通运输工程—道路与铁道工程] U459.1[建筑科学—桥梁与隧道工程]