Parametric study on the sonic transverse jet in supersonic crossflow and analysis of the jet-crossflow interaction instability

Abstract

The sonic transverse jet on a generic high-speed missile is investigated by solving Reynolds-averaged Navier-Stokes (RANS) equations along with Spalart-Allmaras (S-A) one-equation turbulence model. The numerical result is first validated with experimental data. The effects of the jet injection pressure ratio (PR) and angle of injection (AoI) on the transverse jet are studied, and the instability of jet-crossflow interaction is analyzed. The jet injection pressure ratio determines the jet thrust and the flow structure. The blockage effect of the jet reduces the pressure on the model surface in the jet wake region, causing the jet interaction amplification factor to be less than one. The influence of jet flow on the surface pressure distribution of the model produces a negative moment. The reduction of the surface pressure of the flare part slightly reduces the axial force of the model. The normal force increases with the increase of AoI. Appropriately increasing the AoI is helpful to improve the control efficiency, but the AoI should not be so large that the jet-crossflow interaction becomes unstable. Significantly, the current study found that the jet-crossflow interaction becomes unstable in cases of PR around 90, and the instability of the jet-crossflow interaction is the strongest when PR=100. In previous researches, the stability of the transverse jet has always been neglected. Through the analysis of the instability of the jet-crossflow interaction, it is found that the instability in this state is dominated by the unstable interaction between the bow shock and the barrel shock. The instability of jet-crossflow interaction has a significant influence on the control system, which should be considered in the design of the control system.