Experimental study on fire behavior in blind roadway fires at initial sealing time

The distinct structural characteristics of a blind roadway lead to differences in the fire behavior and smoke transport characteristics of oil pool fires in blind roadway and in other scenarios since one end of a blind roadway is a completely sealed heading face while the other end is connected to the main roadway.This study conducted small-scale experiments to investigate the smoke transport characteristics at different initial sealing times in blind roadways.Results show that delayed initial sealing time could cause increasing accumulation of smoke and higher temperature in the blind roadway.However, such pattern was not valid at a distance of 0 m from the fire source since temperature was affected by the flame inclination angle.After sealing, the oxygen volume fraction significantly decreased.As it dropped to a certain value, the fire source would self-extinguish or be in a state of imminent self-extinguishment.Combustion demanded less oxygen, and fresh air in the main roadway would enter the blind roadway through gaps, with the oxygen volume fraction showing an upward trend.Carbon monoxide concentration was generally higher in working conditions with an earlier initial sealing time than that with a delayed initial sealing time as fuel combustion became insufficient within a short time span.This is not explicit in working conditions with a larger oil pan size.