Abstract: Shock wave trains generated by the high-speed flight train in the evacuated tube play an important role in aerodynamic shape design of the vehicle. In view of the constraints of existing equipment and experiment method, the flow field structure generated around the hyper train in the high vacuum tube is numerically simulated by computational fluid dynamics software. Based on the compressible N-S equation, shear stress transport k-w turbulence model and combination method of the dynamic mesh with adaptive mesh. In the simulation, shock wave trains' structure and change law of the flow field inner the tube are studied when the train operates at the speed of 1 250 km/h in the tube with blockage ratio of 0.2 and environment pressure of 10.132 5 Pa(0.000 1 atm). The results show that bow shock wave, normal shock wave, reflected shock wave, lamda shock wave and diamond shape shock wave are produced as the train is flying in the tube. The process that bow shock wave and reflected shock wave are transformed into the normal shock wave in the vicinity of the head car has appeared. The process that reflection shock wave and diamond shape shock wave are produced, developed and disappeared in the vicinity of the mid car has appeared. The development process of the lamda shock wave, reflected shock wave, diamond shape shock wave and normal shock wave appear in the vicinity of the tail car.

Key words: evacuated tube, hyper train, high-speed flight, shock wave trains, motion mesh, dynamic adaptive mesh