Keywords
A steady stream
Circulatory flow
Flow overflow into the gap
Train speed
How to Cite
Abstract
In the paper, the flow induced by the piston effect in metro tunnels is evaluated by numerical analysis according to the train speed, tunnel and train geometry, types of induced flows and other variable characteristics. It is shown that the presence of two phases is characteristic of the piston effect caused by the movement of trains in metro tunnels. In the first phase, the piston effect is characterized by non-stationarity, and in the second phase, the process stabilizes. It is necessary to take into account the influence of the mentioned phases in order to determine the speed of the circulation flows correctly. The speed of the circulation flow driven by the effect of the piston experiences substantial variation considering the degree of non-stationarity of the process in the case of the average statistical length of the metro tunnels (1200 m) and the nominal speed of the train 30-50 km/h.
References
G.N. Abramobich, (1991), Applied gas dynamics, Nauka, Moscow (Russian), 600 p.
V.Ya. Tsodikov, (1975), Subway ventilation and heat supply systems, Nedra, Moscow,568 p.
S. Pan, L. Fan, J.Liu, J. Xie, Y.Sun, N. Cui, L. Zhang, and B. Zheng, (2013), A Review of the Piston Effect in Subway Stations. Hindawi Publishing Corporation, Advances in Mechanical Engineering, Article ID 950205, 7 pages. http://dx.doi.org/10.1155/2013/950205.
S.S. Xu, (1987), Piston wind and environmental conditions in the tunnel, Electric Appliances, no. 3, pp. 42–47.
M.L. González, M.G. Vega, J.M.F. Oro, and E.B. Marigorta, (2014), Numerical modeling of the piston effect in longitudinal ventilation systems for subway tunnels. Tunneling and Underground Space Technology, Volume 40, pp. 22-37.
C. Lin, Y.K. Chuah, and C. Liu, (2008), A study on underground tunnel ventilation for piston effects influenced by draught relief shaft in subway system. Applied Thermal Engineering, 28(5–6), pp 372–379.
F. Wang, M. Wang, S. He, and Y. Deng, (2011), Computational study of effects of traffic force on the ventilation in highway curved tunnels. Tunneling and Underground Space Technology, Volume 26, issue 3, pp. 481–489.
W. Yan, G, Naiping, W. Lihui, and W. Xiping, (2014), A numerical analysis of airflows caused by train-motion and performance evaluation of a subway ventilation system. Volume 23, issue 6, pp. 854-863.
O. Lanchava, N. Ilias, G. Nozadze, S. Radu, R. Moraru, Z. Khokerashvili, and N. Arudashvili, (2017), The Impact of the Piston Effect on the Technological Characteristics of Ventilation in the Subway Tunnels. In Proceedings of 8th International Symposium “Occupational Health and Safety” SESAM-2017, Volume 2, Bucharest, Romania, pp. 342-352.
P. Xue, S. You, J. Chao, and T. Ye, (2014), Numerical investigation of unsteady airflow in subway influenced by piston effect based on dynamic mesh. Tunneling and Underground Space Technology, Volume 40, pp. 174-181.
F.-D. Yuan, and S. You (2007), CFD simulation and optimization of the ventilation for subway side-platform. Tunneling and Underground Space Technology, Volume 22, Issue 4, pp. 474-482.
Z. Li, C. Chen, L. Yan, S. Pan, and L. Zhang, (2017), “Cross-Ventilation” Effect of Piston Wind and Energy-Saving Evaluation for the Ventilation and Air Condition in Subway Station. Proceedings of the 8th International Symposium on Heating, Ventilation and Air Conditioning, pp. 147-156.
N. Meng, L. Hu, L. Wu, L. Yang, S. Zhu, L. Chen, and W. Tang, (2014), Numerical study on the optimization of smoke ventilation mode at the conjunction area between tunnel track and platform in emergency of a train fire at subway station. Tunneling and Underground Space Technology, Volume 40, pp. 151-159.
C.-W. Chiu, T. Lu, H.-T. Chao, and C.-M. Shu, (2014), Performance assessment of video-based fire detection system in tunnel environment. Tunneling and Underground Space Technology, Volume 40, pp. 16-21.
O. Lanchava, N. Ilias, and G. Nozadze, (2017), Some problems for assessment of fire in road tunnels. Supplement of Quality-Access to Success, Bucharest, Vol. 18, Issue S1, pp. 69-72.
N. Ilias, O. Lanchava, and G. Nozadze, (2017), Numerical modelling of fires in road tunnels with longitudinal ventilation system. Supplement of Quality-Access to Success, Bucharest, Vol. 18, Issue S1, pp. 85-88.
O. Lanchava, G. Abashidze, and D. Tsverava, (2017), Securing fire safety for underground structures. Supplement of Quality-Access to Success, Bucharest, Vol. 18, Issue S1, pp. 47-50.
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