Slipstream Deformation in Propeller–Wing–Flap Aerodynamic Interaction

Propeller–wing–flap configurations exhibit highly complex flow patterns due to the aerodynamic interactions among their components. To facilitate effective design of such configurations, a fundamental understanding of these interactions is essential. This paper characterizes the deformation of a propeller slipstream caused by nacelle, wing, and flap interference at various angles of attack and flap deflections, based on validated numerical simulations. We examine different stages and mechanisms of deformation, from immediately behind the propeller to the wake downstream of the wing. Our findings reveal that significant deformation occurs in high-lift conditions before the slipstream physically interacts with the wing, profoundly impacting subsequent deformation. Furthermore, the root vortex system rolls into a strong nacelle vortex that induces crossflow on the wing surface behind the nacelle and dominates the slipstream deformation in the wake. Additionally, the tip vortices stretch around the leading edge and roll into vortex systems aligned with the wing surface, dominating local flow features. These insights improve the understanding of slipstream deformation, helping to improve the aerodynamic performance of propeller–wing–flap systems.