This paper aims to determine the proper cross-sectional area for tunnels on high-speed maglev lines and support the optimization of the airtightness design for high-speed maglev trains. For these purposes, the pressure fluctuations in the tunnel operation of two maglev trains with the speed up to 650km/h were simulated using the 1D compressible unsteady non-homentropic flow model and the method of characteristics. The simulation results were compared to those from the reduced-scale test in Japan and full-scale test in China. The comparison proves that our 1D model is a rational and efficient tool for pressure wave prediction. Through repeated computations of the 1D model, the critical tunnel lengths were obtained. Then, the effects of tunnel length, tunnel cross-sectional area, train speed and train length on maximum pressure variation were identified one by one. The research findings provide a valuable reference for the tunnel and train design on high-speed maglev lines.
high-speed maglev train, numerical simulation, method of characteristics, pressure wave, tunnel
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