Abstract In this study, the smoke control for fire situations in tunnels with naturally ventilated shafts was studied based on a 1/20 reduced-scale tunnel model, and the effects of the longitudinal fire location, shaft settings, and heat release rate (HRR) on the smoke control were discussed. The experimental results show that a worst longitudinal fire location for smoke control exists. Moreover, the critical shaft height for complete smoke exhaustion was studied experimentally and theoretically. According to the experimental results, the critical shaft height is almost independent of the HRR. With increasing shaft length, the critical shaft height decreases first and then remains stable until it finally decreases to zero. Furthermore, it increases with increasing interval between two shafts. In addition, a theoretical model for predicting the critical shaft height was developed and validated. The research results can serve as a useful reference for the design of natural ventilation systems with vertical shafts for the control of tunnel fires.

中文翻译：

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自然通风隧道最严重纵向火灾位置火灾时完全排烟的临界竖井高度

摘要 在本研究中，基于 1/20 缩小比例的隧道模型，研究了自然通风竖井隧道火灾的烟雾控制，以及纵向火灾位置、竖井设置和热释放率 (HRR) 的影响。对烟雾控制进行了讨论。实验结果表明，存在烟气控制最差的纵向火灾位置。此外，对完全排烟的临界井高进行了实验和理论研究。根据实验结果，临界井高几乎与 HRR 无关。随着井筒长度的增加，井筒临界高度先下降，然后保持稳定，直到最终下降到零。此外，它随着两个轴之间的间隔增加而增加。此外，开发并验证了用于预测临界轴高度的理论模型。研究结果可为设计竖井自然通风系统以控制隧道火灾提供有益参考。