The evacuated tube transportation has great potential in the future because of its advantages of energy saving and environmental protection. The train runs in the closed tube at ultra-high speed. Because the heat quantity generated by aerodynamic heating is not easy to spread to external environment and will be accumulate in the tube, the phenomenon that the ambient temperature in the tube will gradually rise will be induced. In this paper, a three-dimensional geometric model and the Shear Stress Transport (SST) κ-ω turbulence model are used to study the influence of initial ambient temperature on the structure of the flow field in the tube. Simulation results show that when the train runs at transonic speed, the supersonic flow region with low temperature and low-pressure is produced in the wake. The structure of the flow field of the wake will change with the initial ambient temperature. And the higher the initial ambient temperature, the shorter the low temperature region in the wake. Considering that the larger temperature difference caused by the low temperature region may increase the temperature stress of the tube and affect the equipment inside the tube. Consequently, the temperature inside the tube can be maintained at a reasonable value to reduce the influence of the low temperature region in the wake on the system.
Since that rollers of a certain type of bridge inspect vehicle were worn seriously in the process of using, a multi-contact dynamic model was set up utilizing ADAMS and SolidWorks. The Poison Model was used to describe the contact relationship between rollers and vertical truss. After dynamic analysis and calculation of contact forces by ADAMS, time-contact force curves were drawn. The curves proved that the results were consistent with the actual situation, so that the simulation process was verified.
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