Numerical Simulation of Air Flow Properties around High Speed Train in Very Long Tunnel

Numerical simulation of air flow disturbed around a train body with different angle of train nose and different velocity of high speed train in a very long tunnel have been made. Three-dimensional flow theory is capable of modeling the effects of interest in the tunnel environment. The scale of train is 2500mmx320mmx427mm lengthxwidthxheigh, and the scale of tunnel is 150mx10.4mx8.2m lengthxwidthxheigh. Train speed is 432km/h, 500km/h and 600km/h respectively. The distributions of pressure, velocities streamline and second flow around high speed train in a very long tunnel space can be obtained by simulating. Results show that the train nose angles and train speed affects the air flow around the train strongly. The pressure drag increases with rising of the nose angles and train speed, and it reaches to the highest value of 23073 Pa when the angle is 600 and 32466Pa as the velocity is 600km/h. The air velocity in the annular space is quite enormous and the maximize value is 178m/s with train nose 600 and 247m/s with train speed 600km/h. 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 very long tunnel.