Numerical Simulation of Air Flow Properties around a Train Body in Long Tunnel Space

A simulation of air flow disturbed around a train body with different angle of train nose in a very long tunnel has been made. Three-dimensional flow theory is capable of modeling the effects of interest in the tunnel environment. The scale of train is 2500mm×320mm×427mm length×width×heigh, and the scale of tunnel is 150m×10.4m×8.2m length×width×heigh. The distributions of pressure, velocity and second flow at a long tunnel space can be obtained by simulating. Results show that the train nose angles affect the air flow around the train strongly. The pressure drag increases with increasing of the nose angles, and it reaches to the highest value of 23073 Pa, when the angle is 600. The air velocity in the annular space is quite enormous and the maximize value is 178m/s. The simulation results can be taken to help us for study the high-speed train energy-consuming, maximum velocity, safety and stabilization when it running in a long tunnel.