Research On Ground Aerodynamic Effect Of Components Under High-speed Train

The development of economic accelerates the development of the high speed railway. Thus situation make related researches on aerodynamics one of the outstanding problems, and attracts many researches around the world.Author of this thesis mainly does theoretical and experimental researches on high-speed train, the focuses is on the ground aerodynamics effect when a train is passing each other in the open air, through the tunnel, and passing each other in the tunnel at different speeds.In these conditions, make use of three-dimensional numerical simulation, calculate the surface of the pressure changes at the train floor and apron board.Maybe the reasons of aerodynamic, lead to fatigue damage, which will affect the safe operation of train.The three conditions in this article are based on three-dimensional, unsteady and compressible fluid equations and the k-εmodel.For passing each other in the open air, through the tunnel, and passing each other in the tunnel were established mathematical models separately.Make use of ICEM meshing, and use the idea of FLUENT finite volume method, as well as moving grid and slip grid, for the simulation to pressure wave and flow field of train floor and apron board. Mainly analyzes the conditions at different speeds, the pressure changes and the law of bullied dynamic effects on floor and apron in different locations, and the pressure changes ofmaximum, minimum and peak-peak trains along the vertical and horizontal variation, according to high-speed train designs.Through numerical simulations of two trains passing each other in the open air, results show that:the pressure change at high-speed train floor and apron board is due to intersection of the two vehicles caused by the pressure wave, and the speed increase along with increasing the pressure amplitude. The two vehicles flush the pressure when the amplitude of the maximum.Through numerical simulations of the train through the tunnel, results show that: the pressure wave speed train entering the tunnel is due to the geometry of the tunnel when the space constraints, the air is compressed in front of train, caused by further compression wave generated and reflected back from the tunnel.Through numerical simulations of two trains passing each othe in the tunnel, results show that:two high-speed trains into the tunnel from both ends of the tunnel, the same as the pressure wave through the tunnel. Two vehicles in the tunnel when meeting occurred, the pressure wave is due to two cars of the pressure wave occurs after the result of superposition.