Smoke flow temperature beneath tunnel ceiling for train fire at subway station: Reduced-scale experiments and correlations

Author:  Meng, N., Wang, Q., Liu, Z. X., Li, X., Yang, H.

Journal: Applied Thermal Engineering

DOI:  10.1016/j.applthermaleng.2017.01.027

Keywords: Train fire, Subway station, Maximum temperature, Longitudinal temperature distribution, Platform-tunnel conjunction door, Reduced-scale experiments, longitudinal ventilation, velocity distributions, maximum temperature, gas temperature, jet, approximation, extraction, platform, channel, profile

Abstract: 

This paper is to investigate the smoke flow temperature beneath tunnel ceiling for a train on fire stopping besides a subway Station. Experiments were carried out in a reduced-scale (1:10) subway station model to study the maximum smoke temperature and the longitudinal temperature distribution beneath the tunnel ceiling by considering platform-tunnel conjunction doors of two types: the full-seal platform screen door (PSD) and the full-height safety door. For the maximum temperature beneath the tunnel ceiling, it is found to be well correlated non-dimensionally with heat release rate by a 3.65 and a 2.92 power law function for the full-seal platform screen door and the full-height safety door, respectively. For the longitudinal temperature distribution along the tunnel ceiling, it can be well correlated by an exponential function for both types of platform-tunnel conjunction doors. Concerning the effect of the door type, the maximum temperature is lower and the longitudinal temperature decays faster for full-height safety door than that for full-seal PSD. This is due to that with the full-height safety door, the effective width of the tunnel ceiling is widened, which results in more heat losses from the smoke flow to the ceiling. (C) 2017 Elsevier Ltd. All rights reserved.