Transportation of wind-smoke flow in full-scale laneway fire experiments

The mechanism of fire smoke movement and its effects on ventilation systems in coal laneways have attracted considerable interest because underground laneway fires threaten safe production. In this study, we investigated the fire characteristics of an intake laneway in a U-shaped working face by conducting a full-scale laneway fire experiment at Kailuan. Results indicated that the two groups of fire combustion states chosen for this study are fuel-controlled, and the amount of CO produced by combustion is significantly influenced by the ventilation conditions. The fire in the laneway has a significant throttling effect on the air intake laneway and return air laneway, which further affects the ventilation system. The smoke temperature decay along the ceiling is not continuous. The temperature drops quickly after the smoke touches the turning wall, and the smoke temperature decay coefficient k is corrected. Besides, the critical velocity and smoke backlayering length equations developed by other researchers are validated. Finally, the smoke thickness and uniform mixing distance are determined.