Study on fresh air of passenger carriage in underground railway

Based on the modeling and analysis of the CO₂ concentration in the tunnels and underground railway with shielding doors, points out that, in winter, with air exhausters on the top of the tracks and at the bottom of the platforms along the railway stations closed and piston air functioning only, the temperature condition can, but the fresh air can not, be satisfied in the tunnels during morning and evening rush hours. The calculation comes out that the least fresh air required in the most unfavorable tunnel during the rush hours is 41 m³/s, which is coincident with the air volume of air exhausters installed on the top of the tracks and at the bottom of the platforms. In conclusion, if shielding doors are installed, the air exhausters must be startedup during the rush hours.