顶部开口自然通风隧道火灾竖井排烟效率研究

通过数值计算方法，研究了顶部开口自然通风隧道竖井的排烟效率。考虑了火源热释放速率、竖井高度、长度和宽度及竖井位置的影响，并与竖井排烟效率计算模型进行对比。研究结果发现：竖井的排烟效率随竖井高度的增加而略微增大；竖井的排烟效率基本不随火源热释放速率的变化而变化；随着竖井长度和宽度地增加，排烟效率大幅增加；此外，当竖井位于顶棚中央时，排烟效率较位于顶棚一侧的排烟效率高，且烟气控制效果好。此外，竖井排烟效率模型可以较好地预测不同竖井尺寸和位置的排烟效率。

Studies on the smoke exhaust efficiency of the vertical shaft in naturally ventilated tunnel fires

The paper focuses on the smoke exhaust efficiency of the vertical shafts in naturally ventilated tunnel fires by using numerical simulation. The impact of the heat release rate (HRR), shaft height, length and width and shaft location on the tunnel ceiling are taken into consideration. The results are compared higher. The smoke exhaust efficiency becomes greater with the increase of the shaft length and width. Besides, it is found that when the shaft is located on the centerline of the tunnel ceiling, more smoke will be exhausted in comparison with that the shaft is located on the tunnel side, and the smoke can be controlled well. Furthermore, the proposed model can predict the smoke exhaust efficiency of the shaft in the naturally ventilated tunnel fires.