冷气溶胶灭火剂作用下狭长隧道火灾的扑救降温过程的数值模拟

为研究大型火灾的远程扑救问题,以一定尺寸的混凝土结构为隧道实型,研究了冷气溶胶灭火剂作用下狭长隧道火灾的扑救降温过程,并运用Gambit建模,ANSYS 15.0软件开展数值模拟研究,最后与公开文献中的试验结果进行对比分析。模拟结果表明:越靠近灭火剂喷口的测量点,其降温越快;最靠近喷口的测量点1在冷气溶胶灭火剂喷射过程中,其温度不断降低,最后降至36 ℃;其他测量点的温度均呈现先升高后降低的趋势,且越靠近喷口的测量点的升温时间越短、降温时间越长。与实验对比发现,4个测量点的初始温度、升温速率、升温时间、最高温度、降温时间、最低温度等参数的模拟值与实验测量值相比吻合度较好,因此,数值模拟可为冷气溶胶灭火剂的灭火性能研究提供参考。

Numerical Simulation of the Cooling Process of a Narrow Tunnel Fire Under the Action of Cold Aerosol Fire Extinguishing Agents

In order to study the long-range fire-fighting problem of large-scale fires, the concrete structure with a certain size was used as the tunnel real type, and the cooling processes of a narrow tunnel under the action of cold aerosol fire extinguishing agents was studied. Moreover, Gambit was used to model and numerical simulation was carried out by ANSYS 15.0 software. Finally, the simulation results were compared with the experimental results in the open literature. The simulation results showed that the closer the distance between the monitoring point and the fire extinguishing agent nozzle, the faster the temperature dropped. With the injection of cold aerosol fire extinguishing agent, the temperature of the measuring point 1, which was closest to the spout, dropped continuously and was finally stable at 36℃, while the temperature of the other three measuring points showed the tendency of declining at the beginning and rising up lately. Moreover, the closer the measurement point to the nozzle was, the longer it heated up and the shorter the cooling time was. Compared with the experimental results, the simulated values of the initial temperature, heating rate, heating time, maximum temperature, cooling time and minimum temperature of the four measuring points were in good agreement with the experimental measurements. Therefore, it was believed that the numerical simulation could be used as a good reference for the study of fire extinguishing performance of cold aerosol fire extinguishing agent.