Abstract: Aerothermal effect produced by the train at high speed cannot be ignored. Based on the two-dimensional axisymmetric compressible N-S governing equation,Sutherland three-equation model and shear stress transport (SST) k-w turbulence model,the flow field structure and aerothermal variation law produced by the hyper train operating at 1 250km/h speed in the low-pressure tube are studied thoroughly by combining two methods of the moving mesh and dynamic adaptive mesh. The results reveal that instantaneous temperature rise on the skin surface is obviously produced when the shock wave hitting the vehicle body in the various process of shock clusters structure such as bow shape shock wave,normal shock wave,reflected shock wave and diamond shape shock wave,etc. Temperature boundary layer begins below the front cab window,gradually thickens along the vehicle body until the maximum thick at the rear vehicle body,then thins at the rear vehicle shoulder,and then continues to thicken until the boundary layer is separated. The temperature rise near the front and rear cab windows is the largest,and the maximum temperature appears mainly near the front cab window. The aerodynamic force of each car and the temperature field around the train almost do not change with constant motion of the train,meaning that there is a balanced state. These results lay a certain foundation on the design of heat-resistant materials for the ultra-high speed evacuated tube train.

Key words: evacuated tube, hyper train, high-speed flight, aerothermal effect, shock train, computational fluid dynamics