高速列车侧包覆式转向架气动减阻研究OA

To further explore aerodynamic drag reduction methods for fairing bogies and reduce the running drag of high-speed trains,a side fairing aerodynamic drag reduction scheme for middle-car bogies with spoilers was designed by referring to existing models of trains with fully fairing head and tail bogies.Nine design schemes were constructed based on two parameters:the gap l between the spoiler and the bogie,and the rear end plate angle α of the bogie.A numerical simulation method for train aerodynamic drag was constructed using the Reynolds-averaged approach based on the Realizable k-ε turbulence model.The effects of different schemes on the aerodynamic drag characteristics of the bogie area,the pressure inside the bogie cabin,and the velocity distribution characteristics were compared and analyzed to explain the drag reduction mechanisms of the proposed drag reduction scheme with side fairing bogies equipped with spoilers.The research results show that adding spoilers to the middle bogie area can prevent airflow from directly impacting the bogie area,reduce the positive pressure area of the bogie and bogie compartment,decrease the airflow dispersion degree within the bogie cabin,and significantly reduce drag.The larger the inclination angle α,the smaller the airflow entering the bogie compartment,and the better the drag reduction effect of the bogie.Increasing the gap l has little effect on the aerodynamic drag of the bogie compartment and bogie,but it does increase the aerodynamic drag generated by the spoiler itself.Simulation results of the optimized design under different parameters indicate that the best drag reduction effect is achieved when the angle of the bogie end plate is 39.84° and the gap between the spoilers is 300 mm.The drag reduction rate for the middle car is 9.38%,and the drag reduction rate for the entire vehicle is 3.02%.The study found that adding spoilers and changing the angle of the bogie end plates can reduce aerodynamic drag without affecting the mechanical structure of the bogie,providing new ideas for further drag reduction in bogie fairing design and a reference for solving the problem of aerodynamic drag reduction in trains.