Study On Aerodynamics Of Super High Speed Maglev Train

The progress of science and technology has promoted the development of high-speed railway.With the continuous improvement of the operation speed of high-speed train,the pursuit of higher speed land vehicle becomes increasingly fierce,so high-speed maglev train emerges as the times require.The aerodynamics problem of the ordinary high-speed wheelrail train is inevitable,so the aerodynamic problem of the maglev train running at super high speed is not to be ignored.Therefore,some common aerodynamics problems of maglev train are studied in this paper.Firstly,the numerical simulation of TR08 maglev trains passing each other at the speed of 430km/h is carried out by using three-dimensional,viscous,unsteady,compressible N-S equation and k-? two equation turbulence model,and the simulation results are compared with the experimental results,which prove that the numerical simulation method is reliable.Different turbulence simulation methods are used to simulate the maglev trains passing each other at the speed of 600km/h,by comparing the simulation results and simulation time,it also proves the reliability of the k-? turbulence simulation method.Secondly,the effects of line conditions(flat ground,embankment,bridge)and track spacing on aerodynamic characteristics of maglev train are studied by using the verified method.The results show that when the maglev train meets each other on the bridge,the amplitude pressure on the surface of the vehicle body is obviously reduced,the maximum lateral force of each car is obviously reduced,and the resistance and lift force of each car have little difference.The yawing moment of the head and tail is obviously reduced,the yaw moment of the middle cars have little difference.The shaking moment of each car of the maglev train is obviously reduced.The pitching moment of head and tail have little difference,and the middle car's pitching moment is increased.With the increase of track spacing,the amplitude pressure of side window and skirt plate decreases gradually,and the amplitude value of lateral force,yawing moment,shaking moment decreases gradually also.The track spacing has little effect on the peak of resistance and lift force.Finally,the aerodynamic characteristics of maglev train passing through the tunnel at super high speed are analyzed by numerical simulation,and the influence of tunnel blocking ratio on the aerodynamic characteristics of maglev train is studied.The results show that,when the maglev train passing through the tunnel,the negative pressure on the surface of the tail and its adjacent middle car is the largest,the lift force of each car is upward,the maximum lift force and the maximum yaw moment of are increasing from head to tail,the yawing moment and side force of the head is the largest,and the shaking moment of the head is the largest.The aerodynamic characteristics of maglev train passing through the tunnel are greatly affected by tunnel blocking ratio.With the increase of blocking ratio,the resistance,lateral force,lift force,yawing moment,pitching moment and shaking moment of maglev train increase gradually.