上、下悬窗对楼梯间烟气控制影响研究

Study of the effect of top and bottom hung windows on smoke control in stairwells

为研究上、下悬窗在楼梯间的烟气控制中的作用,通过数值模拟分析火源位置、窗口开启角度以及外界风速不同时悬窗的相对排烟效率、相对卷吸效率、烟气温度等。结果表明:楼梯间烟囱效应对上悬窗排烟影响较小;同一环境条件下外界风速小于3 m/s时,下悬窗的整体排烟效果普遍比上悬窗高12.1%~37.2%,而上悬窗的整体卷吸冷空气效果普遍比下悬窗高2.9%~15.6%;窗口开启角度为15°~70°时,悬窗开启角度越大,烟气温度控制效果越好,且上悬窗温度控制效果优于下悬窗;悬窗开启角度为15°~30°与30°~70°时的相对排烟效率与相对卷吸效率平均变化率比值均大于1.34,综合考虑温度控制效果及实际情况,楼梯间应优先选用上悬窗,开启角度以30°为宜。

In order to study the role of smoke control of top and bottom hung windows in stairwells,the relative smoke removal efficiency,relative coil suction efficiency,and smoke temperature of hung windows are analyzed by numerical simulation for different fire source positions,window opening angles,and external wind speeds.The results show that:the chimney effect in the stairwell has less influence on the smoke exhaust of the top window;when the outside wind speed is less than 3 m/s under the same environmental conditions,the overall smoke exhaust effect of the bottom window is generally higher than that of the top window by 12.1%~37.2%,and the overall cold air suction effect of the top window is generally higher than that of the bottom window by 2.9%~15.6%;when the window opening angle is 15°~70°,the larger the window opening angle is,the better the smoke temperature control effect is,and the temperature control effect of the top window is better than that of the bottom window;when the window opening angle is 15°~30°and 30°~70°,the average change rate ratio of the relative smoke removal efficiency and the relative volume suction efficiency is greater than 1.34,taking into consideration of the temperature control effect and the actual situation,the stairwell should be prioritized to use the top window,and the opening angle of 30°is preferable.