Aerodynamic Performance of a Low-Speed Blended-Wing-Body Aircraft with Distributed Ducted Fans

The aerodynamic performance of a low-speed, blended-wing-body aircraft with distributed ducted fans was studied. A second-order finite volume flow solver was used to conduct flow simulations around the aircraft. The distributed ducted fans were modeled by applying different boundary conditions at the inlet and outlet of the ducts. Three different geometric models, namely, clean airframe configuration (C1), airframe with a boundary layer ingestion (BLI) fan system (C2), and airframe with a non-BLI fan system (C3), were created to analyze the impact of the BLI fan system on the aerodynamic characteristics of the blended-wing-body aircraft. Then, the aerodynamic performance of these configurations was examined at three design points, namely, climb, cruise, and glide. A comparison of C1 and C3 showed that the installation of the distributed ducted fan system increased the total airframe dissipation in the glide condition. A comparison of the total airframe dissipation of C2 and C3 in the cruise condition revealed that considerable aerodynamic performance improvement was generated by the BLI effects. The aerodynamic performance of the low-speed, blended-wing-body aircraft was sensitive to the installation position of the ducted fan system. The findings of this study provide useful insights into the design of distributed ducted propulsion systems.