Effects of passenger blockage on smoke flow properties in subway station fires

This study investigates the effects of the passenger blockage on the smoke flow properties in the subway station fires. A series of numerical simulations was conducted in a full-scale subway station model under different smoke exhaust volumes (24-96 m³/s) and passenger blockage scenarios. The parameter uncertainty and the model uncertainty were fully analyzed. Results demonstrate that the optimal smoke exhaust volume is 96 m³/s when there is no passenger blockage. When the passenger blockage exists, its effects on the smoke exhaust efficiency, the smoke layer height, and the temperature profile beneath the ceiling are significant. The optimal smoke exhaust volume can only guarantee the passenger's safe evacuation in the blockage scenarios with the low passenger blockage level. For the high passenger blockage level, some measures should be taken to reduce the harm to the passengers near the fire source.