Experimental Study of Smoke Control in Subway Station for Tunnel Area Fire by Water Mist System

Full scale experiments were performed in an underground subway station to investigate the effect of water mist on smoke flow from tunnel area to platform through shield door. Smoke temperature, species concentrations and smoke visibility were measured at different points. Dimensionless variables were introduced to represent the variations of smoke characteristics. The smoke temperature with water mist interaction could be reduced to less than 1/10 of the spill smoke flow. The mass flow rate could be reduced to less than 1/4 of the spill smoke flow. The experimental results indicated that the water mist system could help to reduce smoke temperature and the concentration of toxic species, improving survival conditions for evacuations of passengers.