The Effect Of Bypass Wind Tunnel And Platform Bailout Door On The Thermal Environment In Subway Station

Along with the speediness of city plan, city traffic becomes more and more crowded. Subway is acted as a powerful style to solve the city's traffic problem because of its safety, comfort, speediness and beauty. The velocity of piston wind is increased because of the faster train's speed, the thicker trains'density and the expanded passenger capacity, which makes passengers feel uncomfortable. So it is significant to study utilizing and controlling the piston wind to improve the comfort of the subway station thermal environment.Increasing the area of the bypass wind tunnel will reduce the piston wind to the platform, and adding the height or modifying the form of the bailout door will reduce the effect of the piston wind to thermal environment of platform. Therefore, the purpose of this article is to research the effect on subway station thermal environment caused by bypass wind tunnel and platform bailout door.The article studied on Xiawafang subway station in Tianjin. First of all, the velocity and temperature of piston wind were tested under the condition that whether there is bypass wind tunnel or not and the train pull in or out the platform. Such conclusions are obtained that the bypass wind tunnel has effect on leak-off piston wind definitely, and increasing the area or adding the quantity of the bypass wind tunnel will make for splitting piston wind, reduce the flow inpouring the station and minish the effect of subway station thermal environment.Second, a CFD model of the whole station when the train is pulling in the platform was built, and the validation was made. Such phenomenons were found by simulation and experiment under the condition of 1.4-meter bailout door: the velocity of flow field is too big in the area where passengers wait for the train, and the thermal environment is not comfortable.Finally, in order to improve the thermal environment, two styles of platform bailout doors were put forward: 1.7-meter bailout door (an active open glass door not closed at top), whole high bailout door (an active closed door which separates platform from the rail, the part from 0.5 to 2 meters is glass partition, the others are grilles). And the CFD simulations of subway station thermal environment with different platform bailout doors were made out under the condition that whether there is bypass wind tunnel or not. Such conclusion is obtained by estimating the comfort and first cost: 1.7-meter high bailout door is suitable in the north.This article provides some references for further research to improve subway station thermal environment, it has more important significance.