Two-Dimensional Supersonic Thrust Vectoring Using Staggered Ramps

Abstract

The thrust vectoring performance of a novel nozzle mechanism was numerically investigated. The nozzle was designed for supersonic, air-breathing engines using published engine data, isentropic relationships, and piecewise quartic splines. The mechanism utilizes two staggered, adjustable ramps. A baseline inviscid numerical simulation without ramps verified the nozzle design by comparing the results to the analytical data. Nine ramp configurations were analyzed under steady-state turbulent viscous conditions, using two sets of inlet parameters corresponding to inlet conditions with and without an afterburner (AB). The realizable k – ε model was used to model the turbulence field. Area-weighted integrals of the exit flow showed superior flow deflection with the nonafterburning inlet flow parameters. Calculations of the mean flow deflection angles showed that the flow can be deflected as much as 30 deg in a given direction with the largest ramp length and angle values. The smallest ramp length (less than 5% of the nozzle length) demonstrated as much as 21 deg in flow deflection.