High-Lift Aerodynamics of Integrated Distributed Propulsion Systems with Thrust Vectoring

Recent interest into distributed electric propulsion in aeronautics has motivated exploration of novel approaches for integrating this technology into fixed-wing aircraft. Quasi two-dimensional wind tunnel experiments were conducted with an aero-propulsive airfoil model with ten integrated electric ducted fans and trailing-edge thrust vectoring capability. The experimental model was designed based on a reference aero-propulsive system originally optimized for transonic flight conditions. The model incorporates flow conditioners to separate the capture streamtubes of each fan and transition the circular internal flow into a rectangular nozzle exit. The system angle of attack, thrust coefficient, and nozzle deflection angle were all varied throughout the study. Surface pressure data, aggregate lift, drag, and pitching moment performance, and individual fan thrust data were all collected. Experimental results show an increased lift curve slope and maximum lift coefficient with larger fan thrust alongside larger aerodynamic contributions to drag and pitching moment. Deflection of hinged flaps to vector thrust reduces the airfoil zero-lift and stall angles of attack, similar to traditional trailing-edge flaps. Finally, thrust-drag bookkeeping methods demonstrate how jet momentum and airfoil aerodynamics interact. This experiment intends to highlight the aerodynamic mechanisms through which integrated propulsors couple with airfoils to achieve high-lift performance.