火灾对地铁隧道排烟风机能力的影响研究

研究火灾烟气状态对排烟风机性能的影响,系统分析了地铁隧道火灾烟气的烟囱效应和热阻效应,将地铁隧道系统和排烟风机作为一个整体考虑,分析隧道烟气温度和密度沿程变化规律,建立隧道火灾网络模拟的数学模型,提出在隧道火灾排烟网络模拟时应以质量流量替代体积流量和风机性能的修正方法,研究了隧道火灾烟气流动模拟的数值方法,综合分析地铁隧道火灾的热阻效应、烟囱效应及烟流状态对地铁排烟风机排烟能力的影响。研究方法和结果为地铁隧道火灾烟气控制和事故应急处理决策提供科学依据。

Research of the Influence of Fire upon the Performance of the Exhaust Smoke Fan for the Subway Tunnel Ventilation System

The influence of fire smoke behavior upon exhaust fan performance was theoretically studied. The buoyancy effect and thermal resistance effect of fire smoke in the fire tunnel were systematically analyzed. The influence of the thermal resistance effect, chimney effect as well as the smoke flow behavior on the movement of tunnel fire smoke were comprehensively explored. Considering the underground tunnel ventilation network and the exhaust smoke fan as a whole, keeping in mind the factors such as the changing pattern of the smoke temperature, the density of the smoke flow, the mass flow, instead of the volume flow in the subway fire ventilation simulation, and the correction mechanism of exhaust fan performance influenced by smoke density fluctuations, a mathematical model of tunnel fire ventilation simulation was established and its numerical simulation method of tunnel fire smoke flow was provided. The study method and results will provide a scientific basis for the tunnel fire smoke management and decision making during fire emergency.