High-Fidelity Simulations of Propeller-Wing Interactions in High-Lift Conditions

The recent increased interest in distributed propulsion and electric vertical take-off and landing vehicles have made propeller wake interactions with the aircraft more relevant. The interaction between high-lift wings and propeller slipstreams are still not fully understood and several research efforts are being carried out to improve that knowledge. Lattice-Boltzmann, very large eddy simulations of a propeller-wing-flap configuration are conducted in this work. The simulations are validated with experimental data, with very good agreement of surface static pressure, surface shearlines, and wake total pressure. The complex separation patterns on the flap and their interaction with the slipstream of the propeller are well captured. The effects of grid resolution and laminar-to-turbulent transition are demonstrated. With the simulations validated, they are used to better understand the flow field of this configuration. We find that the angle of attack has a strong effect on how the slipstream is split over the wing, that the tip vortices wrap around the wing leading-edge instead of being cut by it, and that increased circulation stabilizes the tip vortices on the suction side, while making the tip vortices on the pressure side more unstable.