CFD INVESTIGATION OF THRUST VECTORING IN ROCKET NOZZLE VIA JET TAB

Abstract

Thrust Vector Control is a method used to change a flight path or trajectory of a missile by using mechanical systems or secondary injection systems. Jet tab is a one type of mechanical systems. This thesis presents a numerical investigation of the effects of obstacle on a maneuverability of missile. Three nozzle shadow area (10% , 20% and 30%) and obstacle angles changing from 70° to 110° by a step of 20° are investigated and with a variable of obstacle-nozzle gap ratio (0%, 1%,3% and 5%). All cases all have the same initial conditions. Inserting a tab as an obstacle in a supersonic stream generates an oblique shock wave upstream and a high-pressure recirculation zone below the wave. The supersonic flow downstream the oblique shock wave shapes the recirculation zone in a form of a liquid wedge between the separation point and the top of the tab profile. The results ensure that the highest side force to thrust losses ratio at minimum obstacle angle 70°, highest nozzle shadow area 30% and without obstacle-nozzle gap ratio. photo