Research On Windshield Aerodynamic Characteristics And Pneumatic Fatigue Strength Of High Speed Train

As an important connection part of EMU car end, windshield is one of the four connecting technologies, whose shape structure has great influence on the aerodynamic performance and energy consumption as well as the passenger comfort when EMU car is running.Based on the train aerodynamics principle, using method of three-dimensional numerical simulation, and uncompressible and eddy viscosity turbulence model, this thesis used three cars (CRH2) as model and systematically studied the air resistance and flow field characteristics when running in the open air and in crosswind when setting the four different outer windshield structure in car end. And this paper studied the influence of different windshield structures on the setting of air port in car end, comprehensively using the aerodynamic load obtained from the train unit intersection calculation and fatigue life analysis to preliminary analysis the reason of crack phenomenon of the mid-lower parts of EMU’s windshield.Through the research the influence on air resistance of different windshields is obtained. Besides, the new problems which effected by pneumatic effects in practical application is solved, which could provide technical guidance in the design of EMU windshield. The main results in this paper are:①The influence of different windshield structures in car end on drag is large.②According to the special condition that the environment along the railway is poor, when the air port of EMU car is set in the car end, different windshield structures have large influence on the flow field near the air port. For the research approached in this paper, semi-closed outer windshield plan3is the most conducive for fresh air into the air port, and it could guarantee the air quality inside of the train;③The lower place of outer windshield attached to the car body appears crack phenomenon in actual operation process. After fatigue life prediction and analyses of the causing reason, it can be preliminarily proved that one of the causes of the above situation is aerodynamic load.