西安地铁某岛式站台火灾条件下人员疏散环境的数值分析

摘要

本文采用FDS软件,对西安地铁2号线某岛式站台端部火源强度为5 MW的火灾工况进行了数值模拟.在采用事故风机(TVF)+站台空调通风与回风(SEF)+站台下侧排烟的强制通风( UPE)模式下,分析了屏蔽门的不同开启模式对能见度、烟气温度、CO浓度、热辐射和新风风速的影响.结果表明,着火6 min时,强制通风可以使站台和进入站台层的楼梯人口处的温度小于60℃,CO浓度小于312.5 mg/m3 (250 ppm)；全部或部分开启屏蔽门可以实现站台烟气层向站台隧道的抽吸,增加站台安全撤离区域.%In this paper,with the software of FDS,the simulation study was carried out to analyze the fire conditions with the fire intensity of 5 MW occurred at the island-platform station in Xi'an Metro line 2. With the forced ventilation system of tunnel ventilation fan (TVF) ,air conditioning of platform (SEF) and under platform exhaust ( UPE) ,the influences of different open modes of platform screen doors on visibility, smoke temperature, CO concentration, thermal radiation and speed of fresh air were analyzed. Simulation results indicated that the forced ventilation system would make the smoke temperatures of platform and stairs entrance both under 60 ℃ ,and make the CO concentration lower than 312. 5 mg/m 3 (250 ppm) . In addition, with the platform screen doors wholly or partly opened,smoke would be extracted to the tunnels,which could increase the platform security space for people's evacuation.