Novel control method of vortex breakdown over delta wing using dual synthetic jets

To delay the vortex breakdown position of the slender delta wing, this study innovatively proposes the application of control near the Leading-Edge Vortex (LEV) core sweeping path, which is called Coupled Core Rotation Dual Synthetic Jets (CCR-DSJ) control. The results show that the vortex breakdown points at each angle of attack are moved backward after control, and the maximum delayed displacement is 32.4% of the root chord at 30°. Besides, there is a linear relationship between the breakdown position and the angle of attack after control, indicating that CCR-DSJ control has a significant effect on the pressure gradient of the vortex axis. Furthermore, the lift coefficient C_L is enhanced after control, with a maximum C_L increment of 0.078 at 27°, and an effective increment interval of [25°, 32°]. This interval is different from most previous studies, which is directly related to the position of the actuators. According to the lift change mechanism, the angles of attack are divided into three stages: Stage 1 (α = 15°–25°), Stage 2 (α = 25°–32°), and Stage 3 (α = 32°–40°). In conclusion, CCR-DSJ control can significantly change the pressure distribution, thereby offering promising prospects for the flight stage of the slender delta wing.