防火分隔及排烟措施对综合管廊电缆火灾烟气蔓延的影响

Influence of fire separation and smoke extraction measures on the spread of smoke in utility tunnel cable fire

以某综合管廊为研究背景,利用PyroSim模拟软件建立的仿真计算模型,研究了设立挡烟垂壁、改变防火门开启程度、增设排烟设施等情况下的烟气蔓延规律。研究发现:在烟气未充满管廊时,挡烟垂壁会使烟气蔓延速度降低,烟气蔓延速度与挡烟垂壁高度成反比;防火门打开会使火灾烟气蔓延至相邻防火分区,烟气蔓延速率与防火门开启程度成正相关;机械排烟设施会使烟气蔓延速度显著降低,最高降低约50%,当烟气完全充满整个管廊时,会显著降低综合管廊内烟气浓度,烟气层温度最高降幅32℃,能见度最高增加了66%。通过对综合管廊内烟气蔓延的研究,探寻防治综合管廊烟气蔓延的最佳措施,为综合管廊烟气防治的实际工程应用提供参考。

Taking utility tunnel as the research background,a simulation calculation model for fire smoke prevention and control in the utility tunnel was built by PyroSim numerical simulation software and the rules of smoke spread under conditions such as building ceiling screen,changing fire compartmentation tightness,and adding smoke exhaust facilities were explored.According to study results,before the tunnel was filled with smoke,ceiling screens lowered smoke spread rate,and smoke spread rate was inversely proportional to ceiling screen height.When the fire door was opened,fire smoke spread to the adjacent fire compartment,and smoke spread rate was directly proportional to the fire door opening angle.Mechanical smoke exhaust facilities significantly lowered the smoke spread rate by as much as 50%.When the entire tunnel was full of smoke,mechanical smoke exhaust facilities reduced the smoke concentration in the utility tunnel significantly.Smoke layer temperature dropped by as much as 32℃,while visibility improved by as much as 66%.By studying smoke spread in utility tunnel,this paper aims to determine the optimal measures of preventing and controlling smoke spread in utility tunnel.This paper could also provide reference for practical engineering applications in smoke prevention and control in utility tunnel.