Study On Smoke Diffusion And Control Of Subway Station Fire

While promoting the urban traffic development,the subway also brings new problems and challenges to the fire safety.The structure of the subway station is very complex,including dense crowd.Once a fire occurs,it is prone to devastating disaster.Among the many factors,the main cause of casualties is smoke.Therefore,it is significant to study the law of smoke flow and the model of smoke control in subway station.Taking a double island road subway station as the research object,establishing the physical model and carring out the full scale numerical simulation of FDS,studying the effects of different fire position on gas flow and the station hall layer key binding site of smoke screen settings on smoke spread when the subway station fires.Through the distribution of temperature field,CO concentration field and visibility field,the law of smoke flow is obtained,based on the comparison and analysis of the smoke spread and the distribution of the thermal parameters in different smoke exhaust modes,the optimal smoke exhaust mode is selected according to the criteria of the life safety of the subway fire.The results of the study show that:1)The influence of different sources on the flow law and the distribution of the thermal parameters of the flue gas.When the fire occurred on the platform end position,smoke spread rule and closed at one end and narrow channel is similar to that of the closed end near the fire at the temperature must be higher than the other side of the fire,the longitudinal distance of the smoke is longer.When the fire occurs in the middle position of the platform,the law of smoke spread is similar to that of the long andnarrow channel.The distribution of the thermal parameters of the same on both sides of the fire source is symmetrical;2)When the fire occurs at the end of the platform,under the premise of not changing the total amount of exhaust gas and the air supply,the air supply system of the station hall is opened while the platform smoke exhaust system is opened.Not only to control the flue gas in the fire layer,and the temperature,CO concentration and visibility can meet the safety standards,better than other models of smoke exhaust.This paper can provide reference for the study of the subway station smoke design and evacuation to provide a reference basis.