Research on Aerodynamic Characteristics of Ducted Fan System Under Wall Effect

Ducted fans are widely used in the field of unmanned aerial vehicles (UAVs) due to their high efficiency and good safety. This article proposes using ducted fans as both a flight device and a wall adsorption mechanism for a land-air-wall amphibious unmanned platform. When an unmanned platform operates on a wall, the wall will have an impact on the aerodynamic performance of the ducted fan, leading to stability issues for the unmanned platform. In order to explore the aerodynamic performance of the ducted fan on the wall, this paper conducts parametric research on the aerodynamic performance of the ducted wall based on computational fluid dynamics (CFD). The results indicate that the horizontal wall generates a gain in the lift of the ducted fan, and the smaller the distance between the ducted fan and the wall, the more significant the lift gain. For inclined planes, as the inclination angle of the inclined plane increases, the lift of the ducted fan decreases. The influence of the finite near-wall surface on the lift of the ducted fan system is relatively complex, and compared to the infinite horizontal near-wall surface, the aerodynamic characteristics of the ducted fan decrease. The research results provide guidance for the wall motion of land, air, and wall unmanned platforms.