Thrust Vectoring of Double Divergent Nozzle Using Secondary Fluid Injection

In the quest of enhancing the launch capacities of aerospace vehicles, the double divergent nozzles (DDNs) have been investigated during past two decades. In this context, shock vector control (SVC) has drawn immense interest for achieving a high maneuverability by vectoring the direction of thrust. The SVC uses a secondary fluid injection to deflect the primary flow in the nozzle. The present study is aimed at understanding the SVC of a two-dimensional DDN, with an inflection Mach number of 1.5. Equal lengths of the base and extension nozzles are taken into consideration. Numerical investigation is carried out considering three different control parameters: the injector width (IW), the secondary pressure ratio (SPR), and the secondary injection angle. The effect of these parameters on the SVC of DDN at different nozzle pressure ratios (NPRs) are investigated. The momentum imparted by the secondary jet reduces by approximately 51.85% on halving IW. The thrust vector angle increases by approximately 34.74% at Formula: see text when the SPR is increased from 0.7 to 0.9. It is further noticed that downstream inclination of the injector leads to lower thrust losses; however, it also produces lower thrust vector angles as compared to normal and upstream inclinations.