重点排烟隧道火灾烟气最大温升试验研究

Experimental study on maximum temperature rise of smoke in point exhaust tunnel fire

为探究重点排烟隧道火灾时顶棚烟气最大温升规律,通过1∶10的缩尺寸试验,研究隧道火灾时在不同的火源功率、火源位置和排烟量下,火羽流发展过程和隧道纵向中心线上顶棚烟气温度分布规律。根据量纲分析方法,推导出顶棚下方最大温升的数学模型。结果表明:隧道纵向中心线上最高温度的位置不随排烟量而变化,但顶棚烟气最高温度随排烟量的增加而降低、随火源功率和火源与排烟口间距的增加而升高;无量纲最大温升与无量纲火源位置的0.034次幂成正比,且随火源功率的增加而增大。

In order to explore the maximum temperature rise law of ceiling smoke in point exhaust tunnel fire,the 1∶10 experiment was conducted to study the development process of fire plume and the temperature distribution of ceiling smoke in tunnel longitudinal center line under different fire source power,fire location and smoke exhaust rate.According to the dimensional analysis method,the mathematical model of the maximum temperature rise under the ceiling is derived.The results show that the maximum temperature in the longitudinal center line of the tunnel does not change with the smoke exhaust rate,but the maximum temperature in the ceiling decreases with the increase of the smoke exhaust rate,and increases with the increase of the fire source power and the distance between the fire source and the exhaust vent.The dimensionless maximum temperature rise is proportional to the 0.034 power of the dimensionless fire location and increases with the increase of the fire source power.