Experimental Study on Suppressing and Extinguishing of a Diesel Oil Pool Fire with the Water Mist System in a Large-Section Tunnel
(1 School of Transportation and Logistics, Southwest Jiaotong University, Chengdu 611756; 2 Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu 611756)
Abstract：
A 1∶10 reduced-scale model test was conducted based on Froude similarity criterion to study the varia?
tion of physical parameters under different operating pressures at the nozzle in the course of extinguishing a diesel oil pool fire with water mist, especially the variation law of temperature at the ceiling above the fire source, the vertical temperature of the fire plume, the radiation intensity of the fire zone and the longitudinal smoke temperature with or without the water mist. The results show that the maximum vertical temperature appears in the continuous flame zone at 20 cm above the fuel surface for a weak flume fire, and the fatalness of the fire is the most serious in the interim and later stages. The working pressure of the water mist at the nozzle is divided into water mist pressure without fire control (0.2 MPa), water mist pressure with fire control (0.4 MPa) and fire-extinguishing water mist pressure (0.6 MPa, 0.8 MPa) based on testing and temperature data. The densities of the mixture of water vapor and smoke flowing at the tunnel crown as well as the smoke concentration are reduced under the continuous function of a water mist and fire plume. As for the longitudinal smoke temperature change at the tunnel crown, it is divided into
large amplitude attenuation and steady attenuation areas. The fire plume temperature decreases obviously during fire control with the water mist, and the flame temperature is below ignition temperature after cooling
LI Tao- 1,
2 Zhang-Yu-Chun- 2 Ma- Jian- 1 Xiao- Han- 2
.Experimental Study on Suppressing and Extinguishing of a Diesel Oil Pool Fire with the Water Mist System in a Large-Section Tunnel[J] MODERN TUNNELLING TECHNOLOGY, 2017,V54(1): 40-47
2017, Vol. 54 