Research On The Platform Screen Door Impact On Subway Station Environment

Subway system mainly built under the ground is a mass of urban rail transitsystem. With the population and economy developed rapidly, expansion and traffic arebecoming increasingly prominent problem in recently years. Beijing, Shanghai, HongKong, Shenzhen, Guangzhou, Tianjin and other cities have a rapid development insubway. Beijing is the political, cultural and international exchange center that willbuild second-phase 14 subway line by 2012:Line 4,Line 6,Line 8,Line 9 and soon. Subway lines will be operating a total of 19 rail transit in 2015 and reach to 561kilometers. Dense underground railway network abates traffic pressure effectively inthe city, as well as brings more and more urgent issue to be reseached and resoveld onthe environment control and energy consumption.The train piston wind that will be generated when the train runs in the tunnel notonly brings large quantities of air into the front subway station, but also carris largequantities of air into the tunnel from the behind subway station and impacts on theenvironment of subway stations. In addition, a large number of mechanical heat andair conditioning heat extraction will be carried into the front subway station by thepiston-effect when the train runs and inpact on the thermal environment andair-conditioning consumption of the subway station directly. For air-conditioningenergy-saving as well as people's safety, the new subway system has beenincreasingly used the Platform Screen Doors system (PSD). Air flow and heat transfercharacteristics of subway system will be impacted when The PSD is set up within thesubway station.Therefore, the open-type PSD system (including entire-high-security door andsemi-high-security door) will be as the object in this study. By research on somequestions about the train piston wind impacting on the environment of subway stationunder the open-type PSD system condition and the formation mechanism of the trainpiston wind and the impact of factors, will grasp the law of the train piston windimpacting on the environment of subway station. The research focus in the followingareas:Starting from the formation mechanism of train piston wind, based on theone-dimensional aerodynamic theory, build the one-dimensional simplified model ofsubway train piston wind and propose the constant flow one-dimensional flowequation in single-line tunnel without draft. Combining with the computational fluiddynamics (CFD) calculation method, this paper proposes a one-dimension train pistonwind calculation method which is influenced by some factors including the velocity oftrain, geometric parameters of the tunnel and subway train and blocking ratio etc.Based on the calculation method of the one-dimensional train piston wind aboveand its results and combined with CFD calculation analysis software (PHOENICS).Aiming at the subway stations where installs entire-high-security door and semi-high-security door systems and under the typical operating that enters or departsfrom the station, researchs on the inflow or outflow volume of the wind and heatprimarily by the piston-effect. The research results can provide preference for thedesign of subway environment control system and projects application.