隧道内纵向风速对火源上方烟气温度影响的试验

在我国西南某省公路隧道内进行了全尺寸火灾模拟试验,对不同纵向风速、不同火源功率下火源上方典型位置的烟气温度值进行了测量和分析,并对测得的典型结果与理论计算值进行对比.结果表明：试验测得的火源上方最高温升值与理论计算值符合得非常好,该理论计算方法可以用于今后的工程计算之中;另外在隧道内纵向风速较大时,火羽流将产生很大倾斜,导致火源上方顶棚附近的烟气温升不大,单纯采用缆式线型感温火灾探测的方式无法对早期隧道火灾进行报警,应该增加基于其他火灾特征量的火灾探测装置.

Smoke temperature near the tunnel ceiling and above the fire source at different longitudinal ventilation velocities

A series of full scale tests were conducted in two road tunnels. The smoke temperatures near the tunnel ceiling and above the fire source, with different longitudinal ventilation velocities and different typical fire sizes, were measured, presented, and compared with theoretical calculation results. Results suggest that the measured smoke temperature shows good agreement with the calculation results, and is very low when the longitudinal ventilation velocity is fairly large. The cable line-type heat detector can not activate under this condition. Additional fire detection systems based on other fire properties were proposed for use.