Study on Aerodynamic Shape Optimization of Metro Running in the Open Air

Abstract

Based on the three-dimensional incompressible Navier-Stokes equations and the standard k~ε two-equation turbulence model, the flow field around the train is simulated numerically in the case of no wind condition. The influence of the head type and the windshield structure on the flow field distribution and the aerodynamic drag coefficient and the lift coefficient are compared and analyzed. The results show that the aerodynamic performance of the streamlined train is better, the resistance of the streamlined train is obviously reduced, especially the first car, tail car resistance decreased significantly, vehicle resistance decreased by 45.9%. The fully enclosed windshield eliminates the flow separation at the windshield and helps to reduce the resistance of the intermediate car, reducing the percentage by 28.6%.