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Determination of the Required Air Exchange on a Metro Line with a Double-Track Tunnel

The paper investigates the air distribution in the subway tunnel ventilation network with a double-track tunnel, depending on the length of the line under study. The study of static air distribution was carried out in the analytical complex of designing ventilation, air treatment and air conditioning systems of mining enterprises based on the contour flow method. It is shown that when the number of runs on the line is more than two, the provision of air exchange is carried out by the same fans in any mode of operation of tunnel ventilation. At the same time, the maximum parameters of the fans in the normal operation of tunnel ventilation are: 73.8 m/s capacity and 684 Pa pressure, and in emergency mode: 66 m/s capacity and 843 Pa pressure.