Study On The Ventilation Method In Subway Station Tunnel Area With Platform Screen Door

The rapid development of the metro requires to shorten the days for subway construction on the premise of safety. At present, the vetilation of the underground subway station tunnel area with platform screen door system mainly depends on the piston effects and Track Exhaust System(TES) in normal operation mode. Track Exhaust System includes Up Platform Exhaust(UPE) system and Over Track Exhaust (OTE) system. The construction of Over Track Exhaust systems will cause a conflict with the construction of other projects, so as much as possible to cancel the Track Exhaust System or to find other ventilation method instead to the Track Exhaust System on the premise of meeting the requirement of the specifications.This paper take example for Chengdu Metro Line4and use the Subway Environment Simulation program(SES) to simulate and analyze the temperature distribution of the Chengdu Metro Line4tunnel.which with and without the Track Exhaust System, Tunnel temperature can meet the requirement of the specification when there is no Track Exhaust System and the waste heat is only taken away by the piston wind.The highest temperature in subway station tunnel area without TES is2.9degrees Celsius higher than the highest temperature in subway station tunnel area with TES.The factors affecting the piston action ventilation are discussed in this paper, the factors include the tunnel length, the draught relief shaft length, the position of the draught relief shaft and the number of the draught relief shaft, area of the draught relief shaft, the train speed and so on. The typical subway station model is established to research these factors, a feasible method which can increase the piston airflow rate and improve the thermal environment of the tunnel is to change the position of the draught relief shaft and the number of the draught relief shaft.If the piston action ventilation can not completely replace the Track Exhaust System to remove the heat in the tunnel, different mode of mechanical ventilation can be used in the tunnel under the different draught relief shaft position. The variation of the highest temperature in the tunnel area is compared to find the most reasonable mechanical ventilation mode to replace the Track Exhaust System in Chengdu Metro Line4. This mechanical ventilation mode needs to install the draught relief shaft on both side of the station, open the TVF in the draught relief shaft to supply air in the side of the station tunnel entrance and exhaust air in the side of the station tunnel exit, the flow rate of the fans are both100m3/s.