Underground transportation system ventilation by train piston effect

Aradağ, Selin
In this study, the general points of subway ventilation are given, focusing on "Train piston action ventilation". A computer program has been developed to simulate train piston action in underground transportation systems. The program has been named as Trapac (Train piston action). Pressure and velocity distributions are computed along tunnel direction and in time, when a train is passing through a tunnel. inThe partial differential equations that govern the unsteady flow of air in the tunnel are transformed to ordinary differential equations by using the method of characteristics to solve them numerically. Simulations were performed for several cases, including constant and variable speed trains, tunnels with and without ventilation shafts. Case studies are mainly based on Ankara Metro Third Phase Project, so that the results of this study find a basis in the evaluation of station comfort for passengers. The results obtained from simulations were compared with the experimental and numerical studies in literature.


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Citation Formats
S. Aradağ, “Underground transportation system ventilation by train piston effect,” Middle East Technical University, 2002.