Numerical simulation and parameterized investigation of aerodynamic drag performances of high-speed maglev trains

The flow fields around streamlined high-speed maglev trains, including train TR08 and four new trains designed by changing the profile or length of longitudinal projection, were simulated with 3-D compressible viscous fluid theory. In order to evaluate the aerodynamic drag performances of different nose configurations, a non-dimensional parameter defined as total slenderness ratio, which indicated the configuration features, was brought forward as evaluating criterion, the influences of the horizontal and longitudinal projections of train streamlined noses on the drag performances were taken account. Simulation result shows that when other parameters are same, the aerodynamic drag decreases with the length increase of the streamlined nose, while the drag of middle car varies within a small range, when the length of streamlined nose is almost same, the aerodynamic drag of front car with protruding longitudinal profile is less than that of the concave, while that of the rear car is contrary. The order of total slenderness ratios of the five trains is as same as that of aerodynamic drag coefficients. Investigation result shows that increasing the length of streamlined nose is one of the effective ways to decrease train aerodynamic drag, and the total slenderness ratio can well reflect the streamlined configuration influence on train drag.