Active Flow Control of a High-Speed Train Wake Using Synthetic Jets

To improve the aerodynamic performance of a high-speed train (HST) and reduce the safety risk of wake movement on platform commuters, trackside workers, and surrounding infrastructure, an active flow control method based on synthetic jets (SJs) is proposed to suppress the wake of the HST. The wake of the HST controlled by synthetic jets with different momentum coefficients is simulated by the improved delayed detached eddy simulation (IDDES) method embedded in ANSYS Fluent. Then, the slipstream velocity, aerodynamic force, velocity field in the wake region are analyzed. The results show that synthetic jets can effectively reduce the amplitude of the slipstream velocity in the wake region, the aerodynamic drag, and the fluctuation of the aerodynamic side force of the tail car. Furthermore, the synthetic jets delay the flow separation on the side of the tail car through periodic ejection and suction, and then attenuate the vortex motion in the wake region.