Study of the Unmanned Aerial Vehicle Propeller Performances Near Ceiling: Experimental, Numerical and CFD-based Approaches

Abstract The ceiling effect is a significant factor for unmanned aerial vehicle (UAV) missions that require close flight in the proximity of top planar boundaries such as inverted docking, perching, and flight in a confined space. In this study, the ceiling effect on a 5.5-inch propeller of a small UAV and a 9-inch of a medium-sized UAV was modeled and simulated using computational fluid dynamics (CFD) with multiple reference frame (MRF) method. The result was then validated by an experimental method at propeller speeds ranging from 5000 to 9000 RPM. For the near-ceiling region, computational fluid dynamics and experiment setup results for the propeller thrust were compared with the Cheeseman and Bennett model, the Hayden model, and also using the Conyers model. The results showed a close agreement between the computational fluid dynamics and experimental results, as well to the theoretical models, with some errors. Further, the validated CFD results were used to investigate the extreme-near ceiling region, which is not currently covered by the theoretical models. Our contribution in this study wishes to provide more understanding of such effects in the extreme near ceiling on a single-rotor model by using the velocity streamlines, thus possibly expand to multi-rotor unmanned aerial vehicles (UAVs) of different sizes in future research.