高压细水雾对城市地下管廊火灾的降温效果

Cooling efficiency of high pressure water mist on fire in urban underground pipe gallery

为探究城市地下管廊火灾蔓延的有效控制方法,研究基于高压细水雾作用下的城市地下管廊火灾蔓延规律。建立尺寸为3.1m×12.0m×3.6m的城市地下管廊模型,根据火源位置、喷头数量、平均粒径、喷头压力等的不同设置工况,研究高压细水雾的降温性能、粒径对降温效果的影响。研究结果表明,受地下管廊结构与壁面的影响,可燃物在燃烧时形成单侧燃烧并发生轰燃。高压细水雾喷头开启后轰燃次数减少,管廊内温度明显下降,燃烧时间缩短;雾滴粒径对高压细水雾的降温灭火性能起主要影响,粒径为100μm时降温效率最高。

In order to study the fire spread control method of urban underground pipe gallery,the fire spread of underground pipe gallery under high pressure water mist was investigated.A 3.1 m×12.0 m×3.6 m urban underground pipeline gallery model was established.Fire scenarios were set according to the location of fire source,the number of sprinklers,the average particle size and the pressure of sprinklers,etc.The cooling performance and effect of particle size of high pressure water mist on cooling effect were studied.The results showed that,under the influence of the construction and wall surface of the underground pipe gallery,the fire source forms single side burning and flashover when the high pressure water mist is not opened.The times of flashover decreases after the opening of the high pressure water mist,and the temperature in the pipe gallery decreases obviously,the combustion time is shortened.The particle size of water droplet has the dominant effect on the cooling and extinguishing performance of high pressure water mist,and the cooling efficiency of high pressure water mist is the highest when the particle size of water droplet is 100μm.