Study On The Influence Of Pistons Wind On An Island Station On Thermal Environment During Pull In Process

With the development of the MTR, air distribution and thermal environment in the subway station have increasingly become a focus in MTR environment control design. What's more, with the increase in the subway traffic capacity and train speed, the effect of piston wind on the station flow field will become more significant.The Cao changpo station of the Xi'an Metro Line 2 was chosen as prototype for study, which is simplified and assumed reasonably, and the appropriately physical model was built up. Three-dimensional turbulence numerical simulation method was used, and the control equations are discrete by the finite volume method. Moving mesh generation technology was used to solve the problems of the geometry changes in solution area and related regions in the adjacent calculation area. The movements of the trains, including starting, accelerating, constant speed, decelerating and stopping stages, are simulated by the Profile files. By simulating the train's movement in three kinds of working conditions, the influence of the piston wind during the movement of the train on the temperature field and velocity field of the stations and the platforms, is studied. It is shown that the wall temperature of the subway tunnels and the train's speed have effect on the temperature field and the velocity field of the tunnels and the platforms, and the lower tunnel wall temperature and velocity ,more comfort able condition can be achieved.