The combustion and smoke spread characteristics of wood crib fires under sprinkler and mechanical smoke exhaust

Abstract

Wood crib fires are a significant concern for fire safety, as they involve complex combustion and smoke dispersion behaviours that pose challenges for both prevention and control. This study investigated the combustion characteristics and smoke dispersion of wood crib fires, focusing on the role of mechanical smoke exhaust and sprinkler systems in fire safety management. The results showed that mechanical smoke exhaust increased the pyrolysis rate of the wood crib, with flame height rising by approximately 8.3% compared to natural combustion. The smoke layer height was effectively controlled by the mechanical exhaust, stabilizing at approximately 2.5 m when the system was activated. When the sprinkler system was turned on, flame height and combustion intensity were suppressed. The maximum flame height was reduced to 50% of that observed during natural combustion. Smoke temperature distribution along the height direction decreased linearly. A height of 1.0 m was reached by the smoke layer, which had decreased significantly. When both systems were used together, flame height and temperature were reduced by 15.8% and 53.7%, respectively, compared to natural combustion. The smoke layer reached a height of 1.5 m. These findings offer insights and guidance for optimizing fire prevention and control in wood crib fires.