This paper employs the Improved Delayed Detached Eddy Simulation(IDDES)method to conduct a numerical simulation study on the aerodynamic characteristics of a 200 km/h EMU train meeting a 350 km/h EMU train inside a tunnel.The study considers the effects of different meeting positions on aerodynamic forces,train surface pressure,and air-tightness requirements.The results show that meeting at the tunnel entrance significantly increases train drag,while at different positions inside the tunnel,drag may turn negative due to the reflection of pressure waves.The variation in lateral forces is relatively consistent across different positions,but reaches a maximum at the tunnel exit.Changes in lift are minor,with the most significant negative peak occurring at the tunnel's midpoint.Pressure analysis reveals that the head car experiences the most severe pressure fluctuations when meeting at the tunnel's midpoint.At this position,the highest air-tightness requirement is observed,with the critical dynamic airtightness index reaching 10.2 s.The findings of this study provide reference data for the aerodynamic design and airtightness standards of high-speed trains in tunnels,contributing to improved train safety and comfort.
关键词
动车组/隧道/气动效应/气密性/IDDES
Key words
multiple unit train/tunnel/aerodynamic effects/airtightness/IDDES
万方数据