Thrust vectoring through fluid injection in an axisymmetrical supersonic nozzle: Theoretical and computational study

Abstract

Numerical and modeling study has been accomplished to investigate the effects of a secondary injection in an axisymmetrical, convergent-divergent nozzle for fluidic thrust vectoring purpose. The annular secondary gas injection in the axisymmetrical nozzle causes complex effects (boundary layer separation, shock wave interaction....). The present paper focuses on the results of some computational and modeling investigations, where the influence of some parameters (pressure ratios, injection slot size and location, injected mass flow rates...) are studied. To perform this work, a 3D Navier-Stokes calculations, with several turbulence models were used. Previously, a theoretical model of a secondary injection in a primary jet had been constructed. To characterize the separation zone caused by the injection, different correlations have been tested. The results indicate that fluidic annular injection in an axisymmetrical nozzle can produce significant thrust-vector angles up to 16 degrees. The nozzle pressure ratio and the mass flow rate ratio were in the range of 2 to 10 and 2 to 7% respectively. Some results were validated on NASA experiments in both 2D and axisymmetric tests.