Experimental study of temperature profile in underground corridor of various widths induced by fire in an adjacent compartment

Corridor-compartment fire, i.e., fire plume ejected through the door of the compartment and spread along the adjacent corridor, is a fundamental scientific problem in underground space, which is very important for the evacuation and firefighting. Nevertheless, the relevant studies are still very limited for quantifying the temperature evolutions inside the compartment as well as the corridor ceiling flow induced by corridor-compartment fire scenarios for various compartment door sizes and corridor widths. In the present study, a reduced-scale corridor-compartment experimental model was established, with four opening (door) sizes and eight corridor widths considered. The fuel burning mass loss rate (or instantaneous HRR) and the temperature profile inside the compartment and corridor were measured and analyzed. Results show that: (1) A non-dimensional correlation of the upper-part temperature rise inside the compartment could be found for various opening sizes and corridor widths in over-ventilated and under-ventilated condition, respectively. (2) The temperatures of the ceiling flow at the corner between corridor wall and corridor ceiling increases slowly before over-ventilated and then increases significantly after reaching under-ventilated condition with fire growth, it decreases significantly with the corridor width increasing, due to the change of ventilation condition. A non-dimensional model which considering the effect of corridor width for different opening sizes is proposed for the temperature decay profile of ceiling flow at the corner between corridor wall and corridor ceiling. This model could predict the temperature in underground corridor of various widths induced by a fire in an adjacent compartment, and then analyze and assess the fire thermal hazard on the compartment and corridor.

Automated summary

Corridor-compartment fire is a crucial issue for evacuation and firefighting in underground spaces. However, limited studies have been conducted to quantify the temperature changes inside the compartment and the corridor ceiling flow induced by such fires with different compartment door sizes and corridor widths. In this study, a reduced-scale experimental model was used to measure and analyze the burning rate and temperature distribution. The results show that there is a non-dimensional correlation for the temperature rise inside the compartment under over-ventilated and under-ventilated conditions. The temperatures of the ceiling flow at the corner between the corridor wall and ceiling increase slowly before reaching under-ventilated condition and decrease significantly with increasing corridor width. A non-dimensional model considering the effect of corridor width is proposed to predict the temperature in underground corridors and assess the fire thermal hazard.