岛式地铁车站站台层火灾烟气控制方案研究
Study on smoke control scheme for platform floor fire inisland subway stations
摘要：
在某岛式地铁车站热烟测试中发现,先启动站台排烟系统、2 min后手动打开站台门启动隧道风机联合排烟的站台烟气控制方案,将会导致烟气大范围沉降,站台能见度降低,威胁疏散人员安全。本文通过数值模拟,提出了3种站台烟气控制方案,分析了烟气蔓延过程、温度分布、CO浓度分布及能见度。研究发现:在保证下行风速满足的情况下,采用在站台门上方轨顶排热风道设置侧排烟口、利用车站隧道排热风机和站台排烟系统联合排烟的烟气控制方案效果最佳;而采用开启站台门两侧首尾滑动门、启动隧道风机与站台排烟系统联合排烟的烟气控制方案,以及采用开启靠近火源侧站台门、启动隧道风机与站台排烟系统联合排烟的烟气控制方案,在开启站台门后40～50 s左右,站台能见度将不能达到人员安全疏散的要求;对于已建成投运、采用开启靠近火源侧站台门、启动隧道风机与站台排烟系统联合排烟的烟气控制方案的车站,可在满足最小清晰高度的情况下,适当加深储烟仓厚度,同时应严格把握手动打开站台门、启动隧道风机辅助排烟的时间。
Abstract：
During the hot smoke test of an island subway station, it is found that the platform smoke control scheme of starting the platform smoke exhaust system first, and after 2 minutes manually opening the platform door to start the tunnel fan for combined smoke exhaust will lead to a large range of smoke settlement, and reduce the visibility of the platform, threatening the safety of evacuees. In this paper, three platform smoke control schemes are presented by numerical simulation, and the smoke spread process, temperature field distribution, CO concentration distribution, and visibility are analysed. It is found that under the condition that the downgoing wind speed is satisfied, the smoke control scheme of setting side smoke outlets on the rail top hot air exhaust duct above the platform door and using the station tunnel exhaust fan and the platform smoke exhaust system to jointly exhaust smoke has the best effect. However, if the smoke control scheme is to open the front and rear sliding doors on both sides of the platform door to start the joint smoke exhaust of the tunnel fan and the platform smoke exhaust system, and the smoke control scheme is to open the platform door near the fire source to start the joint smoke exhaust of the tunnel fan and the platform smoke exhaust system, the visibility of the platform will not meet the requirements of safe evacuation of personnel about 40 to 50 seconds after the platform door is opened. For the stations that are completed and put into operation and adopt a smoke control scheme of opening the platform door near the fire source to start the joint smoke exhaust of the tunnel fan and the platform smoke exhaust system, the thickness of the smoke storage bin can be appropriately deepened under the condition of meeting the minimum clear height, and the time of manually opening the platform door to start the tunnel fan for auxiliary smoke exhaust should be strictly controlled.
Keywords:island subway station; platform; fire; smoke control; tunnel fan; smoke exhaust system; hot smoke test