热压及室外风压对高层建筑楼梯间加压送风系统影响的网络模拟分析

Network simulation for stairwell pressurization supply air system in high-rise buildings with influence of stack effect and wind pressure

以两幢高度不同的高层建筑为例,利用网络模拟软件CONTAM3.0模拟分析了热压及室外风压单独作用和二者耦合作用对楼梯间加压送风效果的影响。结果显示:建筑高度、建筑内外温差、室外风的风向和风速都会影响楼梯间加压送风效果;由建筑内外温差产生的热压作用会导致楼梯间压力重新分布,冬季的热压作用极可能导致楼梯间的压力小于安全阈值,使加压送风系统失效;当热压和室外风压耦合作用时,最不利情况是夏季建筑上部迎风面房间着火和冬季建筑下部迎风面房间着火,这两种情况下着火层前室门处的压差均降至6Pa左右,远低于规范规定的25Pa,导致楼梯间加压送风系统失效。

Taking two high-rise buildings as examples,simulates the influence of the stack effect and the wind pressure on the stairwell pressurization supply air system separately and simultaneously with the network simulation software CONTAM3.0.The result shows that the building height,the temperature difference between inside and outside of the building,the direction and magnitude of outdoor wind velocity will all have an effect on the stairwell pressurization supply air system.The stack effect caused by the temperature difference between inside and outside of the building will result in redistribution of pressure in the stairwell,and the stack effect is very likely to cause the pressure in the stairwell smaller than the safety threshold,which may cause the stairwell pressurization supply air system fail.With the coupling of the stack effect and the outdoor wind pressure,the most unfavorable situations occur when the windward fire room is on upper floor in summer or on lower floor in winter,in which the pressure difference between lobby and corridor is down to about 6 Pa,which is much less than 25 Pa stipulated in the standards,and that may cause the malfunction of stairwell pressurization supply air system.