外界风下机场航站楼自然排烟模式的数值模拟研究

Numerical simulation study of airport terminal natural exhaust mode under outside wind

机场航站楼通常采用顶窗和多侧高侧窗作为自然排烟窗,当发生火灾时,其开窗模式对自然排烟效果有一定的影响。以某机场航站楼为例,考虑出发大厅顶窗及多侧高侧窗的启闭状态组合,设置7种开窗模式。通过FDS软件模拟,研究外界风下,开窗模式与火源功率对航站楼到达危险时间的影响。在只打开顶窗的模式下,到达危险时间t与火源功率Q均满足关系式:t=x0+A/(1+10^(bQ-c)),其中x0、b、c随着风速的增大而减小,A随着风速的增大而增大。考虑到人员安全疏散,航站楼出发大厅火源功率应控制在6MW以内。若火源功率大于6MW,当外界风速小于等于5m/s时,应采用打开所有高侧窗和顶窗的开窗模式;当外界风速大于5m/s时,烟气会倒灌进入航站楼,影响人员安全疏散,此时应采取关闭迎风侧高侧窗,打开顶窗和其他侧高侧窗的开窗模式。

In the airport terminal buildings,top windows and multi-side high-side windows are usually employed as natural exhaust windows for improving fire safety.With an airport terminal as an example,this paper uses the FDS software to study the effect of windowing mode and fire load on hazard occurrence time of the terminal building under the wind.The combination of opening and closing states of the departure hall top window and multi-side high-side windows,with seven kinds of windowing modes,is considered.When only the top window is opened,the hazard occurrence time t and the fire source power Q satisfy the relation:t=x 0+A/(1+10^(bQ-c)),where x 0,b,and c increase with increasing outside wind speed,and A decreases with increasing outside wind speed.For safety evacuation of personnel,the fire source power of the terminal building departure hall should be controlled within 6 MW.If the fire source power is higher than 6 MW and the outside wind speed is less than or equal to 5 m/s,all high side windows and top windows should be opened.When the outside wind speed is greater than 5 m/s,the smoke will be backfilled into the terminal building,thus affecting the safety evacuation of personnel.In this case,the high-side window on the windward side should be closed,while the top window and other side of high-side window should be opened.