Aerodynamic Characteristics of Intercity High-Speed Trains Meeting in Tunnels

[Objective] The aerodynamic loads and instantaneous pressure changes generated when intercity high-speed trains meet in tunnels seriously affect the train operation safety and the passengers′ aerodynamic comfort. Therefore, it is necessary to study the aerodynamic characteristics of intercity high-speed trains meeting in tunnels. [Method] Based on the numerical calculation method of aerodynamics, the aerodynamic loads and the pressure fluctuations inside certain intercity high-speed trains meeting in tunnels are studied. The pressure changes on the train surface and on the tunnel wall, the changes in the lateral force cast on every train car, and the pressure changes inside the carriage are analyzed. [Result & Conclusion] The amplitudes of the train surface pressures on the meeting side and on the other side are basically the same. The amplitude of the tunnel wall pressure is basically symmetrically distributed along the middle of the tunnel. The lateral force and the overturning moment experienced by the train are approximately proportional to the square of the meeting speed of the trains. The instantaneous pressure fluctuations inside the train meet the passengers′ aerodynamic ride comfort requirements that the pressure change is no more than 500 Pa within 1 s and no more than 800 Pa within 3 s.