Experimental research into air distribution in a terminal subway station

Abstract

The paper presents the findings of an in situ research into velocities of air flow initiated by piston effect at the terminal station Garin-Mikhailovsky’s Square of the Novosibirsk Metro. The researchers calculate actual volume of the cold outdoor air inlet to the station and find the relationship between the air flow velocities and train speeds. It is shown that at the outdoor air temperature below −10 °C, the operating warm air curtains fail to ensure heating of the inlet cold outdoor air up to the rated temperature.Based on the full-scale experiment results, the network mathematical model of air flows is refined so that to take into account piston effect in a terminal subway station. The data of the computational exercises on the adjusted mathematical model of air distribution are provided, and the dependences of air volumes in the station entrance halls on the train speed in the Sibirskaya station–Garin-Mikhailovsky’s Square station tunnel are plotted. The most efficient method to reduce the cold outdoor air inlet at the station is to change speeds of the incoming and outgoing trains. In the recommended scenario, trains arrive at a speed of 60 km/h and depart at a speed of 30 km/h. In this case, the average velocity of the inlet cold outdoor air flow in the station entrance hall is decreased 2 times as compared with the air volume in the current speed mode of the subway trains. Furthermore, the power of the operating warm air curtains becomes sufficient to maintain the rated air temperature in the station entrance halls given the outdoor air temperature is −27 °C and above.