针对目前地铁车站站厅层公共区的排烟工况较为粗狂，一般为开启一个防烟分区内的全部排烟口，在一定程度对原有烟气层的破坏，排烟效率地下的问题，本文针对郑州市某城市轨道交通车站站厅层公共区设置了8种不同的排烟工况，着重研究了开启不同位置排烟口的排烟效率，本文通过FDS模拟，得到了不同工况下能见度、温度、co浓度随时间的分布图，得出：1）地铁车站站厅层公共区发生火灾时，并非开启的排烟口越多越好，而是要根据排烟风口的开启位置来定；2）开启烟气水平蔓延阶段的排烟口会对烟气水平分层流动造成干扰，加剧上层烟气与下层冷空气的热交换与物质交换，导致温度为60℃的高度层及能见度为10m的高度层降低，不利于人员疏散；3）当火源在站厅层公共区中部排烟系统最不利点时，站厅层公共区中部挡烟垂壁附近的排烟风口需正常打开，以便顺利排出该处聚集的火灾烟气。

In response to the current rough smoke exhaust conditions in the public area of the subway station hall, which generally involves opening all smoke exhaust outlets in one smoke control zone, the existing smoke exhaust layer is damaged to a certain extent and the smoke exhaust efficiency is underground. This article focuses on eight different smoke exhaust conditions in the public area of a certain urban rail transit station hall in Zhengzhou, and studies the smoke exhaust efficiency of opening smoke exhaust outlets in different positions. Through FDS simulation, this article obtains the distribution maps of visibility, temperature, and CO concentration over time under different working conditions. It is concluded that: 1) When a fire occurs in the public area of the subway station hall, the more smoke exhaust outlets are opened, the better, but it is determined by the opening position of the smoke exhaust outlet; 2) Opening the smoke exhaust outlet during the horizontal spread stage of smoke will interfere with the horizontal stratified flow of smoke, intensify the heat and material exchange between the upper layer of smoke and the lower layer of cold air, resulting in a decrease in the height layer with a temperature of 60 ℃ and a visibility of 10m, which is not conducive to personnel evacuation; 3) The smoke exhaust outlet near the smoke blocking vertical wall in the middle of the public area on the station hall level needs to be opened normally to smoothly discharge the accumulated fire smoke in that area.

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国家重点研发计划资助项目( 2019YFC0605105)