The objective is to evaluate the transient effects of a reaction control jet on the aerodynamic performance of a generic interceptor missile operating at supersonic flight conditions. Three-dimensional computations of the highly turbulent flowfield produced by a pulsed, supersonic, lateral-jet control thruster interacting with the supersonic freestream and missile boundary layer of a generic interceptor missile are evaluated at different altitudes and thruster conditions. A generic missile interceptor configuration consisting of a long, slender body containing fixed dorsal and tail fins is simulated. Parametric computational fluid dynamic solutions are obtained at altitude conditions corresponding to 19.7 and 35.1 km for 1) steady-state conditions with the lateral control jet turned off, 2) steady-state conditions with the lateral control jet turned on, 3) transient jet startup conditions, and 4) transient jet shutdown conditions. A thermally and calorically perfect gas with a specific heat ratio equal to 1.4 was assumed for both the Mach number 5 freestream and Mach number 3 lateral jet. Vehicle forces and moments are assessed from each solution by integrating the surface pressures and viscous shear stresses computed on the missile surfaces. These results are used to determine the influence of the jet-interaction effects on the transient aerodynamic performance of the missile. The analysis predicts strong transient influences for the integrated normal force and pitching moment.
