Research On The Distribution Of Pollutants In The Platform Of Screen Door Subway Station

With the increasing of the flow of people and deterioration of the outdoor environment,subway indoor air quality has become an important research direction.This paper studies the screen door subway station in Beijing,by the means of numerical simulation,The temperature,carbon dioxide concentration and particle of this subway station was been researched.The environmental characteristics and pollutant characteristics of the subway station are analyzed,and the applicability of different methods in the diffusion of pollutants in the subway station is discussed.A physical model and a mathematical model of the shield gate metro transfer station are established,and the personnel simplification method is put forward.The accuracy of the model is tested by the measured method.The experimental results show that the model has a large fluctuation range,but the overall trend is consistent with the experimental results.Simulation of the ventilation system under different factors in the control of carbon dioxide of the subway station has been done.Through the simulation,The recommended value for the ventilation system of air volume 12 m3/(h×p),this amount of ventilation can control the carbon dioxide about 0.18%,temperature around 27? in breath area.Recent traffic flow and long-term ventilation system has been discussed.Discuss personnel load running different ventilation systems,obtained 50% of the load of carbon dioxide dilution effect rather poor conclusions.Simulation of the condition when screen doors are opened show that screen doors will impact at air of any station layer.Screen doors open at different positions on different layers of other stations.This effect is periodicity.It proposed using 12m3/(h × p)supply when the screen door closed,using 30 m3/(h × p)when the screen door opened.In terms of the distribution of particles,simulation under different concentrations of particle and air supply was been done.Simulation shows particle concentration values in breathing plane smaller than the outdoor concentration.The larger the amount of air supply,particle concentration in the breathing zone of the plane closer to the value of outdoor.High particle concentration site and place mostly in the station hall near the stairs,installing an air purifier can effectively reduce the influence on other platforms when the screen door open.