Objective With higher demands from citizens for urban commuting, high-speed metro trains operating at speeds of 100 km/h and above have emerged. The increase in train operating speed will intensify the pressure fluctuation effect inside the train, which in turn affects passengers’ riding comfort. Therefore, it is necessary to explore the main factors that influence the pressure fluctuations inside and outside the metro train when entering tunnels.

Method A numerical simulation model for the operation of high-speed metro trains in tunnels is established, and the accuracy and calculation method of this model is verified. Three key factors influencing pressure fluctuations inside the train, i.e. train streamlined length, train operating speed, and blockage ratio, are selected. Finally, a variety of calculation models are built to explore the impact of these three factors on pressure fluctuations inside and outside the train, respectively. Based on the orthogonal test method and response surface methodology, the interaction effects among the influencing factors are analyzed.

Result & Conclusion The pressure fluctuations inside and outside the train have a strong positive correlation with the train speed, a strong negative correlation with the blocking ratio, and a certain negative correlation with the streamlined length of the train. An interaction effect exists between the train's operating speed and the blockage ratio. As the blockage ratio increases, the amplitude of the pressure fluctuation inside the train within 1 second becomes more sensitive to train operating speed changes. A certain interaction effect is also observed between the train's streamlined length and the blockage ratio. As the blockage ratio decreases, the impact of the train's streamlined length on the amplitude of the pressure fluctuation inside the train within 1 second diminishes. The interaction effect between the train's streamlined length and its operating speed is not significant.