subway station

The subway station is a special location with very dense crowd. Because subway station situates in underground, people can not evacuate to ground easily. Once a fire occurs in subway station, it is very dangerous for people to stay in it. So, a well designed smoke exhaust system must be installed in subway station to control the smoke’s propagation and descending.

Velocity fields on the platform area and flow rate of the smoke extraction system were experimentally measured under the different fan-operation modes in an actual subway station in Beijing. The velocity at the four tunnels connected with the station and velocity at the stairs between platform and concourses were obtained. Through simulation based on the measured results, the smoke velocity, temperature and concentration in case of station fire under the different fan-operation modes were analysed, and the optimal smoke extraction mode was proposed.

According to the cold climate in winter, a new novel ventilation system was put forward based on the analysis of the heat distribution at the subway station in Harbin. There was no special heating system in winter for subway station with such a ventilation system. In this paper, three dimensional model of the subway station was built, a mathematical model of the novel ventilation system was developed based on the k-ε standard turbulence model, and computational fluid dynamics (CFD) simulations for the ventilation system were performed to clarify the conditions of the temperature fields.