不同类型双层玻璃幕墙火灾烟气流动特性对比研究

采用大涡模拟方法研究整体式、走廊式和竖井式三类常用双层玻璃幕墙的火灾烟气流动特性。结果表明,整体式双层玻璃幕墙内的烟气在竖直方向上的蔓延速度很快,但空腔内烟气温度相对较低,约为180℃;走廊式双层玻璃幕墙可以将火灾烟气完全限制在着火楼层的玻璃幕墙空腔内,但空腔内最高温度高达270℃;竖井式双层玻璃幕墙不能完全阻止烟气向其他楼层玻璃幕墙空腔内的蔓延,但与整体式双层玻璃幕墙相比,进入其他楼层的烟气量明显减少,玻璃幕墙空腔内的最高温度介于上述两种双层玻璃幕墙空腔内最高温度值之间。在实际应用中,应充分考虑不同类型双层玻璃幕墙的消防问题,并有针对性的采取防护措施,降低其火灾危险性。

A Comparison Study of Features of Smoke with Different Double Glass Walls

This paper makes a study of smoke movement with three different double glass walls of unitary,corridor and shaft types by the large eddy simulation. The results show that the smoke with the double glass moves quickly in a vertical direction with a comparatively low temperature of 180 ℃; the corridor glass walls can prevent the smoke from spreading outside of a burning floor with a temperature of 270 ℃; the shaft glass wall cannot hold back the spread of smoke to other floors. Compared with the unitary glass walls,the shaft walls can reduce the smoke movement to other floors. The temperature with corridor glass walls is between those of other two types walls. It is necessary to take into account the fire prevention with different types of walls to reduce fire risk.