Abstract
In recent years, railway construction in China is in a rapid development stage. As a result, more and more long-profile large-distance tunnels are designed and constructed. To accommodate for rapid deployment of vehicular tunnels, it is necessary to enlarge its profile, namely, to reduce the tunnel blockage ratio since train cross-section remains unchanged. This study has analyzed the impact of blockage ratio on tunnel smoke controlling critical ventilation velocity (CVV) as well as the smoke flow behaviors around the train on fire and in its immediate surroundings, using CFD numerical simulation. The results show that in certain fires, CVV decreases as the blockage ratio increases, and the opposite is also true while CVV increases gradually accelerates, while, temperatures near the top of tunnel roof decrease gradually as the blockage ratio decreases. The smaller the blockage ratio, the smaller the critical high temperature area. As a train passes by, the peak ventilation velocity increases as the blockage ratio increases. Results of this study could provide a theoretical basis for safety design as well as operation of long-large interval tunnels to prevent possible disasters.
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References
The movement of smoke in horizontal passages against an air flow, Fire Research Note 723/1968. Fire Res Station (1968)
Bettis, R.J., Jagger, S.F., Macmillan, A.J.R., et al.: Interim Validation of Tunnel Fire Consequence Models; Summary of Phase 1 Tests. The Health and Safety Laboratory Report IR/L/FR/94/2. The Health and Safety Executive, UK (1994)
Zhang, S., Yao, Y., Zhu, K., et al.: Prediction of smoke back-layering length under different longitudinal ventilations in the subway tunnel with metro train. Tunn. Undergr. Space Technol. 53, 13–21 (2016)
Chen, L.F., Hu, L.H., Tang, W., et al.: Studies on buoyancy driven two-directional smoke flow layering length with combination of point extraction and longitudinal ventilation in tunnel fires. Fire Saf. J. 59, 94–101 (2013)
Mounesan, M., Talaee, M.R., Molatefi, H.: Investigation of effective parameters on critical ventilation velocity in underground tunnels. Mech. Eng. 48(1) 2016
Oka, Y., Atkinson, G.T.: Control of smoke flow in tunnel fires. Fire Saf. J. 25(4), 305–322 (1995)
Wu, Y., Bakar, M.Z.A.: Control of smoke flow in tunnel fires using longitudinal ventilation systems—a study of the critical velocity. Fire Safety J. 35(4), 363–390
Li, Y.Z., Lei, B., Ingason, H.: Study of critical velocity and backlayering length in longitudinally ventilated tunnel fires. Fire Saf. J. 45(6), 361–370 (2010)
Lee, S.R., Hong, S.R.: An experimental study of the effect of the aspect ratio on the critical velocity in longitudinal ventilation tunnel fires. J. Fire Sci. 23(2), 119–138 (2005)
Tsai, K.C., Chen, H.H., Lee, S.K.: Critical ventilation velocity for multi-source tunnel fires. J. Wind Eng. Ind. Aerodyn. 98(10–11), 650–660 (2010)
Lee, S.C., Kim, S.I.: The Effect of Grid Number and the Location and Size of the Fire Source on the Critical Velocity in a Road Tunnel Fire, vol. 14, issue 3 (2012)
Roh, J.S., Ryou, H.S., Kim, D.H.: Critical velocity and burning rate in pool fire during longitudinal ventilation. Tunn. Undergr. Space Technol. 22(3), 262–271 (2007)
Ko, G.H., Kim, S.R., Hong, S.R., et al.: An experimental study on the effect of slope on the critical velocity in tunnel fires. J. Fire Sci. 28(1), 27–47 (2010)
Jianping, Y., Zheng, F., Haifeng, H., et al.: Model of Critical Velocity for Fire Ventilation in Horizontal Tunnels, vol. 31, issue 6, pp. 66–70 (2009)
Longhua, Hu, Huo, Ran, Wang, Haobo, et al.: Experiment of fire smoke temperature and layer stratification height distribution characteristic along highway tunnel. China J. Highw. Trans. 19(6), 79–82 (2006)
Kunsch, J.P.: Modelling of tunnel fires and experimental validation. PAMM 5(1), 677–678 (2005)
Vauquelin, O., Wu, Y.: Influence of tunnel width on longitudinal smoke control. Fire Saf. J. 41(6), 420–426 (2006)
Acknowledgements
This study is financially supported by the National Science Fund for Excellent Young Scholars through grant 51622403, the National Natural Science Foundation of China (NSFC) through grants 51674152, the National Key Research and Development Project of China through grant 2016YFC0802500. This work is also funded by the Fundamental Research Funds for China Academy of Safety Science and Technology through grants 2018JBKY02 and 2017JBKY03.
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Li, J., Shi, C., Chen, C., He, L., Xu, X., Wu, B. (2019). Research on Blockage Ratio Effects on Large-Profile Tunnel Fire Behaviors. In: Chang, X. (eds) Proceedings of the 11th International Mine Ventilation Congress. Springer, Singapore. https://doi.org/10.1007/978-981-13-1420-9_52
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DOI: https://doi.org/10.1007/978-981-13-1420-9_52
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