Investigation on the influence of injection angle in supersonic flow with hybrid flow control

The supersonic flow (Ma=2.0) past micro-ramps and micro vortex generator jet have been simulated to suppress boundary layer separation and improve the characteristics of isolators. In this paper, the effects of skew and pitching injection angles on the flow field are analyzed. The pitched angle has little effect on the x position of the separation region in the corner, but greatly changes the length of the separation region and the corner vortex strength. The smallest separation region is generated at pitching angles 45° and 60°. The height of streamwise vortex can be reduced by relatively high pitching angle due to the interactions between the high speed flow and the micro vortex generator. With the increasing skew angle, the flow quality in the isolator increases in the beginning and then decreases. A similar tendency is observed in the ability of the isolator withstanding back pressure. Excessively high skew angle leads to asymmetry flow filed, and the best control action is obtained at 45° skewed angle for the given pitched angle of 30°. Relatively low pitching angle and skew angle are helpful in reducing the distortion coefficient and total pressure loss coefficient.