Study of the Change of the Shaft Shape on the Influence to Aerodynamics Effect of the High-Speed Metro Tunnel

Abstract

When a metro train passes through the shaft, it will lead to severe pressure fluctuations on surfaces of tunnel and train due to the sudden change of tunnel cross section. Based on the three-dimensional, compressible and unsteady N-S equation method, this paper simulates aerodynamic problems caused by trains when they pass through the airshafts at the speed of 140 km/h by the means of constructing four middle shaft models, one is the real shaft, the other three are the simplifications. Time delays generated on trains’ surfaces after trains pass through shafts in the three simplifications’ model, but on tunnels’ surfaces from entering portals for the different corridor sizes. The tendency of max pressure, min pressure and pressure amplitude at trains’ and tunnels’ surfaces is consistent in four kinds of models. But the different area of shafts’ corridor sizes cause the most used model gets the maximum pressure amplitude, the real model gets the minimum pressure amplitude, and the two simplifications’ are the middle.