细水雾对障碍物遮挡火源抑制作用的数值研究

以大涡模拟、混合物分数模拟和欧拉-拉格朗日粒子运动描述法为基础,采用火灾动力学软件FDS研究了细水雾对障碍物不同程度遮挡火的抑制作用,通过改变雾滴粒径、喷头操作压力来分析细水雾对不同遮挡情况油池火的抑制灭火作用。结果表明:当火源被障碍物完全遮挡时,操作压力低于1MPa,细水雾很难达到抑制作用,当压力达到4MPa以上时,细水雾能够将温度控制在较低范围内;细水雾粒径小于50μm时,细水雾对障碍物遮挡火有较好的抑制作用;从整体来看,随着细水雾粒径的减小、压力的升高,细水雾对障碍物遮挡火的抑制作用逐渐增强。

Numerical Simulation on the Suppression Effect of Water Mist on Fire with Screen

The effect of water mist on suppressing pool fire with screen was numerically simulated based on Large Eddy Simulation(LES),Mixture Fraction Combustion model and Euler-Lagrange method.The suppression effect of water mist on fire with screen was studied through changing water droplet size and nozzle pressure.The results show that,while the fire is screened completely,it is hard to be suppressed with water pressure below 1 MPa;while the operation pressure is up to 4 MPa,the temperature could be controlled in a lower level;while the water droplet size is smaller than 50 μm,water mist has a good suppression effect on fire with screen.On the whole,when reducing water droplet size and increasing water pressure,the suppression efficiency will be enhanced.