Abstract In theory, if the plug-holing phenomenon can be effectively eliminated, the application of natural ventilation with vertical shaft will no longer be limited to shallow buried tunnels, or even extended to deep buried tunnels. Researches have validated that the board-coupled shaft (BCS) can efficiently eliminate the plug-holing phenomenon and promote the smoke extraction performance in a shallow buried tunnel. The purpose of this paper is to explore whether the BCS is effective and has stable smoke extraction performance in deep buried tunnels. Experiments were conducted in a 1/20 scale model tunnel, and the height of the board-coupled shaft applied in this study is 5 times the height of the tunnel height. The influence of heat release rate (HRR) and board location on the smoke extraction performance was investigated. Experimental results indicated that the BCS is effective and has stable smoke extraction performance for the deep buried tunnel applied in this study. Besides, it can be found that the smoke extraction efficiency of the BCS will be improved and the improvement in the smoke extraction performance with BCS is stable when the power of the fire source increases. Also, the optimal board location for the BCS to achieve the peak smoke extraction performance was obtained and the peak smoke extraction performance of the BCS is about 1.451–1.457 times of the traditional shaft. Beyond that, two dimensionless correlations were developed under the general condition that the first shaft cannot extract the entirety of the smoke, one is the correlation function for analyzing the smoke temperature difference and the CO concentration in the shaft; the other is the correlation for predicting the dimensionless volume flow rate under different HRRs and board locations. These studies may contribute positive significance for promoting the application of natural ventilation with vertical shafts.

中文翻译：

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深埋隧道连板竖井自然通风排烟性能试验研究

摘要 理论上，如果能有效消除堵孔现象，竖井自然通风的应用将不再局限于浅埋隧道，甚至扩展到深埋隧道。研究验证了板联轴（BCS）可以有效消除塞孔现象，提高浅埋隧道的排烟性能。本文旨在探讨BCS在深埋隧道中是否有效并具有稳定的排烟性能。试验在1/20比例模型隧道中进行，本研究采用的板式联轴器高度为隧道高度的5倍。研究了热释放率 (HRR) 和板位置对排烟性能的影响。实验结果表明，BCS对本研究应用的深埋隧道有效且具有稳定的排烟性能。此外，可以发现当火源功率增加时，BCS的排烟效率会提高，并且BCS的排烟性能的提高是稳定的。此外，获得了 BCS 达到峰值排烟性能的最佳板位置，BCS 的峰值排烟性能约为传统竖井的 1.451-1.457 倍。除此之外，在第一个竖井不能提取全部烟气的一般条件下，建立了两种无量纲相关，一个是分析烟温差和竖井内CO浓度的相关函数；另一个是预测不同 HRR 和板位置下的无量纲体积流量的相关性。这些研究可能对促进竖井自然通风的应用具有积极意义。