Citation

Gao Y, Luo Y, Li Z, Zhang Y, Yu Y, Li T. China Saf. Sci. J. 2022; 32(3): 109-115.

Copyright

(Copyright © 2022, China Occupational Safety and Health Association, Publisher Gai Xue bao)

DOI

10.16265/j.cnki.issn1003-3033.2022.03.015

PMID

unavailable

Abstract

In order to study smoke flow characteristics in case of fire in bifurcation tunnels, a series of fire experiments in the 1 : 10 scale tunnel model were carried out with fire source located in bifurcation tunnels. Two heat release rates (15. 9 and 31. 9 kW) and 7 ventilation wind speeds (0, 0. 45, 0. 60, 0. 75, 1. 0, 1. 3 and 1. 6 m/s) were selected, and smoke's back-layering length, temperature distribution in the main tunnel and bifurcation tunnel under different longitudinal ventilation speeds were analyzed. The results show that when the fire source is located in bifurcation tunnels, smoke back-layering length in the main tunnel conforms to THOMAS prediction model, but coefficient Cd is much smaller than previous research results in single-hole tunnel. The dimensionless smoke temperature distribution in the main tunnel agrees with longitudinal temperature attenuation model, with coefficient k attenuating in a power function along with increase of longitudinal ventilation, and that in bifurcation tunnel corresponds with longitudinal temperature attenuation model too, but with coefficient k' demonstrating linear attenuation as longitudinal ventilation increases. © 2022 China Safety Science Journal. All rights reserved.

Language: zh