区间隧道纵向分区烟气控制研究(1)——数值模拟分析

Smoke Zoning Control in Metro Tunnel(1)——Numerical Simulation

在地铁区间隧道中,列车头部和尾部发生火灾时采用纵向通风烟气控制模式可使疏散人群与烟气分离,但列车中部发生火灾时,下风向人员将不得不在烟气笼罩下撤离.采取集中风道排烟或增设服务隧道的烟控方式虽安全性较高,但土建投资也高.本文提出的隧道纵向分区烟气控制模式利用防烟隔板将隧道划分成行驶区和疏散通道2个防烟分区,列车发生火灾时可组织乘客就地疏散,采取适当通风方式既能保障人员安全疏散又能减少火灾对隧道和线路的危害.数值模拟结果表明通过向疏散通道正压送风能阻止烟气的侵入,利用烟气下沉前的时间经疏散门进入疏散通道内,再向两端车站及站外撤离,乘客疏散过程可在无烟的环境中进行;待乘客进入疏散通道后再启动行驶区一侧的排烟系统,可以避免长时间火灾高温对隧道结构和线路的损害,消防人员也可从行驶区的上风侧或以疏散通道为屏障尽量接近火场.

In case of a train is firing in subway tunnel, take longitudinal ventilation for a hre occurs at me front or the rear of the train can separate the crowd from the smoke, while a fire occurs at the central of the train some people have to evacuate though the smoke. Although semi-transverse or full-transverse ventila- tion is more security, the investment is too higher to afford. This paper presents a new method to control the smoke with zoning mode, which using clapboard to divide the tunnel into two zones, the traffic zone and the evacuation channel zone, and appropriate ventilation can prevent smoke from the evacuation channel. The numerical simulation results of smoke zoning control in tunnel indicate that no matter wherever fire happens, we can supply fresh air in evacuation channel, and then the unilateral ventilation of smoke can be carried out after the evacuation of passengers, which can effectively ensure the safety of evacuation as well as lower high-temperature in a fire hazard. It can afford a safety routes for firemen from windward in traffic zone or evacuation channel approach to the fire source synchronized.