Design And Experimental Study On Smoke Exhaust Linkage System Of Subway Station

With the development of urbanization in China,the population in the city has rapidly increased.In most of the major cities in China,urban rail transit is an important part of the urban public passenger transportation system.And it is a large-capacity passenger transportation system.Once a subway fire breaks out,the rescue mission will be very difficult.The fire at the station floor is more complex than that in other areas of the station.First of all,in the building structure,the platform is located at the bottom of the station,the vertical distance is deep,and the distance to escape is far.Secondly,in the event of a fire,hot smoke will rise at the bottom and will spread rapidly.Finally,the station equipment smoke prevention equipment is mainly installed in the equipment area,such as dedicated exhaust fan,tunnel fan,etc.Under the platform fire conditions,the platform exhaust outlet is at the end of the air duct,the exhaust capacity is insufficient,and the previous design should be considered to enhance smoke exhaust capacity,how to use the tunnel fan,platform doors to exhaust the smoke.This paper began with a theoretical analysis to understand the smoke control methods for subway fires,the analysis of smoke prevention and control.The design of interfaces between various fire-fighting systems and equipment after adopting an integrated monitoring system,and how to improve the protection against fire conditions smoke exhaust capacity was also investigated.The study focused on the movement of smoke under the fire conditions of urban subway station platform,combined with the control mode of station smoke exhaust system,designed and checked the station's smoke control system,and in view of the fire at different locations on the platform.The smoke emission of the platform fire was improved by using the reasonable switching method of the platform door system.Finally,through the on-site hot smoke experiment,the exhaust smoke effect of the platform was further verified,and the smoke prevention and control system at the station was optimized.The research results have certain reference value for the design of subway ventilation weak current system.The hot smoke test on platform fires showed that when only the exhaust fan is turned on,the smoke spreads quickly and cannot provide enough power to control its spread,the platform layer has accumulated a lot of smoke,the temperature of the smoke is high.The wind speed in most areas of the escalator cannot meet the specification requirements,leading to the spread of smoke to the station hall,which is detrimental to the escape and evacuation of personnel.When the public area exhaust fan and the TVF fans at both ends of the station are turned on,the exhaust fan assists to exhaust the smoke,the air conditioning system of the station hall sends fresh air.At the same time,according to the different positions of the platform fire,the corresponding position platform doors are opened.At this time,the wind speed at the escalator can meet the requirements of the standard,and the direction of the wind speed is opposite to the direction to the escape of people.The height of the smoke layer is above the breathing height of the people within 300s,and the temperature of the evacuation path area is less than 20? at the height of 1.5m,which is effectively ensure the safety evacuation of personnel.