Vertical Landing Aerodynamics of Reusable Rocket Vehicle

Abstract

The aerodynamic characteristics of a vertical landing rocket are affected by its engine plume in the landing phase. The influences of interaction of the engine plume with the freestream around the vehicle on the aerodynamic characteristics are studied experimentally aiming to realize safe landing of the vertical landing rocket. The aerodynamic forces and surface pressure distributions are measured using a scaled model of a reusable rocket vehicle in low-speed wind tunnels. The flow field around the vehicle model is visualized using the particle image velocimetry (PIV) method. Results show that the aerodynamic characteristics, such as the drag force and pitching moment, are strongly affected by the change in the base pressure distributions and reattachment of a separation flow around the vehicle. Nomenclature C D : drag coefficient, () 2 2 S V D ∞ ρ C p : pressure coefficient, () () 2 2 S V P P surface ∞ ∞ − ρ D : aerodynamic drag force [N] F j : jet thrust [N] f j : momentum flux of jet [kgm/s 2 ] f ∞ : momentum flux of freestream [kgm/s 2 ] M j : Mach number of jet at nozzle exit P e : nozzle exit pressure [Pa] P surface : surface pressure [Pa] P 0 : thrust chamber pressure [Pa] S : base area [m 2 ] S nozzle : nozzle exit area [m 2 ] T 0 : thrust chamber temperature [K] V ∞ : freestream velocity [m/s] V j : jet velocity (at nozzle exit) [m/s] α : angle of attack [deg] ρ : freestream density [kg/m 3 ] ρ j : jet density [kg/m 3 ]