Aerodynamic behavior of streamlined noses with vision cameras mounted at different positions in an autonomous urban train

Vision cameras are key components in autonomous trains for obtaining road information and ensuring operational safety. Mounting vision cameras alters the streamlined structure of a train and affects its aerodynamic behavior. In this study, the improved delayed detached eddy simulation based on the shear stress transport k-ω model was used to investigate the aerodynamic behavior of streamlined noses mounted with vision cameras on a 160-km/h autonomous urban train. The aerodynamic forces and flow structures of the streamlined head/tail with and without a camera mounted on different positions were compared. The results indicated that mounting the camera on the lower part of the streamlined nose had minimal impact on the pressure distribution and surrounding flow, with no significant change in the aerodynamic forces. In contrast, mounting the camera on the upper part significantly altered the vortex size and distribution around the streamlined noses, resulting in a 27% increase in the drag force of the streamlined head and an 11% decrease in the drag force of the streamlined tail. Furthermore, the surface pressure on the streamlined noses changed significantly.