Abstract
A running traffic train induces piston wind in the subway. The influence of piston wind on fire smoke propagation in subway is investigated numerically. The flow field structure in fire platform, temperature contours and velocity profiles at certain positions are obtained at various scenarios respectively. Three methods are adopted to reduce the impact of piston wind on smoke layers. Results show that large-scale vortexes and tremendous horizontal inertial force would be produced under the influence of piston wind; and that smoke stratification would be broken totally under its influence, therefore toxic gas would spread to subway hall through stairs. So the former smoke management system in a subway station becomes less effective. Results also show that combination of enhanced the volume flux of pressurization at the subway hall and lowering the height of smoke screens around stairs are necessary to restrict hazard smoke on the floor on fire. The bypass wind tunnel and ventilation shaft are useful to attenuate the magnitude of piston wind.
Highlights
The overall length of worldwide subway has been increasing due to traffic congestion, which is an outstanding problem for metropolises
Fire smoke propagation without piston wind is solved, and this mode is denoted as mode 2 which indicate there is no train running in the tunnel
The third phase is up to 182 s during which period the vehicle runs by the platform, its tail moves out of the tunnel at 175 s and its head arrives at the right tunnel and at 182 s the whole vehicle gets inside the tunnel
Summary
The overall length of worldwide subway has been increasing due to traffic congestion, which is an outstanding problem for metropolises. Journal of Civil Engineering and Management, 2015, 21(4): 514–523 and numerical studies on smoke movement and control in subway stations. Zhang et al (2008) conducted a numerical simulation of kerosene fire/smoke spread over the subway stations platform by the software CFD and SIMPLE algorithm for fluid mechanics, including five different types of smoke exhaust systems. Y. Kim (2007) analysed the unsteady three-dimensional flow in the subway tunnel caused by a train movement, presented the pressure and air velocity variations with time by using software CFX4, and made a confirmation by a 1/20 scale model. The paper study the interaction of piston wind with fire smoke in platform layer, and propose valid methods to optimize smoke manage system of subway stations
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
