机械排烟下高压细水雾灭火效果的数值模拟

目的分析机械通风情况下,高压细水雾技术对单室油火的灭火效果,为高压细水雾灭火系统在地下大空间的应用奠定基础.方法采用火灾动力学模拟软件(FDS),应用大涡模拟方法的场模型、两相流模型、辐射模型,模拟分析火源中心面的温度、灭火时间、CO质量浓度等参数.结果得到在1 MW、1.5 MW、2.5 MW火灾功率下,不同通风情况的10 MPa高压细水雾喷头的灭火特性参数,对比、分析了火源上方0.5 m处的温度以及1.5 m截面的CO平均质量浓度的变化曲线.结论随着火灾功率的增加,机械排烟对10 MPa高压细水雾灭火效果的负面效应减小,机械排烟和高压细水雾灭火技术联合作用对2.5 MW火灾的灭火效果更佳.

Numerical Simulation of the Co- Operation Effect of High- Pressure Water Mist Fire Protection and Mechanical Ventilation

The single sprinkler,with high-pressure water mist fire protection system in a single room was carried out to find out the co-operation fire extinguishing effect in the different powers pool fire,in the case of mechanical ventilation.FDS(Fire Dynamic Simulator),including LES(Large Eddy Simulator)model,two-phase model and radiation model,is adopted in this paper.Middle-face temperature,fire extinguish time,CO concentration were gained.By contrast and analysis,the fire power below 2.5 MW,as the fire power increasing,fire extinguish time was decreased,the negative influence of mechanical ventilation was lessened,which indicates the result is better.It will help a lot for fire prevention and control of large space building.