风速对高层建筑凹型外墙火灾烟气扩散的影响

Effect of wind speed on smoke diffusion of concave exterior wall fire in high-rise buildings

为研究环境风对高层住宅凹型外墙底部烟气扩散的影响,对高层住宅凹槽内火灾烟气温度、扩散速度、浓度等特性进行数值模拟。取外墙凹槽的侧墙长度与侧墙间距之比为结构因子,设置不同工况进行对比分析。结果表明:相同结构因子、不同风速下的各高度处温度符合指数分布;获得了烟气脱离建筑中部壁面的临界风速与结构因子的关系模型,为高层住宅凹型外墙尺寸设计提供参考。结构因子为1时底层窗户破裂时间相对最大。

To study the influence of ambient wind on smoke diffusion at the bottom of concave exterior walls of high-rise residential buildings,the characteristics of smoke such as temperature,speed and concentration in concave walls of high-rise residential buildings were simulated numerically.Take the ratio of the length of the side wall and the distance between the side walls of the groove of the outer wall as the structural factor,different working conditions were set for comparative analysis.It is found that the temperature at different heights of the same structural factor is exponentially distributed under different wind speeds.The relationship model between critical wind speed of flue gas leaving the central wall of the building and the size of the structural factor was obtained to guide the dimension design of concave exterior wall of high-rise residential buildings.The rupture time of the bottom window is relatively the maximum when the structural factor is 1.