Experimental Study on Aerodynamic Drag Characteristics by Train Underbody Shape Variation

Wind tunnel tests are performed with changes of bogie shapes in order to investigate the aerodynamic drag variation of Korean high speed train HEMU-430x according to bogie types. Experiments are performed with the Boundary Layer Removal System with 1/20 scale model of 3-car and with the ground plate with 5-car model respectively. The aerodynamic drag by applying the streamlined to the bogie section is much smaller than for applications of the normal bogie and the bogie cover. The big reduction rates by the streamlined means that the aerodynamic drag due to the normal bogie occupies comparatively large parts of whole drag for the high speed train. Applying the bogie cover can also make the train’s whole drag reduced and the train’s running performance improved.