Ducted Fan Experimental Investigation and Shape Optimization Using Computational Fluid Dynamics

View Video Presentation: https://doi.org/10.2514/6.2022-0304.vid The research in ducted fans gained the attention of aerospace engineers, focusing on decreasing the tip losses during the last years. Varying the cross-section of the duct affects the pressure and velocity of the in- and out-airflow, changing the propulsion performance. The current contribution presents an experimental investigation alongside a computational study to optimize the duct shape for better-ducted fan efficiency. The experimental investigation is carried out in an open-circuit low-speed wind tunnel, where the inlet flow velocity and the fan’s rotational speed are varied. Measurements are extracted for the pressure jump across the fan, velocity before and after the fan, thrust force, and rotational speed of the fan. Optimizing the duct shape is achieved through Computational Fluid Dynamics (CFD) analyses, in which the actuator disk approach is used as a representation of the fan blades. The actuator disk, defined from the experimental results, works as a source term to replace the fan effect. The surrogate modeling algorithm was integrated with the CFD simulations to search for the optimal geometric design of the inlet and outlet of the duct, which will enhance the performance of the ducted fan by maximizing the thrust and the pressure jump.