Experimental Study on Temperature Distribution Characteristics of Inclined Tunnel Fire Under the Longitudinal Wind and the Ceiling Multi‐Point Centralized Smoke Exhaust Mode

ABSTRACT Tunnel fire is one of the major challenges that cannot be ignored in the safe operation of tunnels. Considering the structural characteristics of tunnel fires, it is feasible to use longitudinal ventilation coupled with multi‐point centralized smoke exhaust in subway tunnel engineering. Combining common slope tunnels, it is of great significance to investigate the ceiling temperature characteristics of such tunnels. Experimental testing was conducted. The results indicate that there is a strong linear relationship between the ceiling maximum temperature and the tunnel slope. A prediction formula for the ceiling maximum temperature of a sloping subway ventilation tunnel with a multi‐point centralized smoke exhaust mode has been proposed. Based on the double exponential addition temperature decay model, the decay trend upstream and downstream of the exhaust vent was discussed. The constant coefficient remains basically unchanged; the decay index coefficient is linearly related to the tunnel slope, and the reduction coefficient is linearly related to the smoke exhaust volume. A tunnel ceiling temperature decay model with a multi‐point centralized smoke exhaust mode affected by tunnel slope was proposed.