Wind tunnel tests of hovering propellers in the transition state of Quad-Plane

• Published in: Bulletin of the Polish Academy of Sciences. Technical sciences Vol. 69; no. 6
• Main Authors: Pobikrowska, Katarzyna, Goetzendorf-Grabowski, Tomasz
• Format: Journal Article
• Language: English
• Published: Warsaw Polish Academy of Sciences 2021
• Subjects: Aerodynamic characteristics; aerodynamics; Aircraft configurations; Airframes; Axial flow; Design; Designers; Electric motors; Energy consumption; Fixed wings; Fuselages; Hovering; hybrid uav; Inflow; propeller; Propellers; propulsion; Propulsion systems; Unmanned aerial vehicles; Vertical takeoff aircraft; vtol; wind tunnel; Wind tunnel testing; Wind tunnels
• DOI: 10.24425/bpasts.2021.138821
• ISSN: 0239-7528

The following paper presents wind tunnel investigation of aerodynamic characteristics of hovering propellers. This propulsion system may be applied on a lightweight Quad Plane VTOL (Vertical Take-Off and Landing) UAV (Unmanned Aerial Vehicle). A Quad Plane is a configuration consisting of a quadcopter design combined with a conventional twin-boom airplane. This kind of design should therefore incorporate the advantages of both types of vehicles in terms of agility and long endurance. However, those benefits may come with a cost of worse performance and higher energy consumption. The characteristics of a fixed-wing aircraft and propellers in axial inflow are well documented, less attention is put to non-axial flow cases. VTOL propellers of a hybrid UAV are subject to a multitude of conditions – various inflow speeds and angles, changing RPMs, interference between propellers and between nearby aerodynamic structures. The tested system presented in this article consists of four electric motors with two coaxial pairs of propellers mounted on one of the fuselage beams. Such a configuration is often chosen by designers of small and medium hybrid UAVs. There is a need for studies of clean, efficient ways of transporting, and this article can aid future designers of a new type of electric UAVs.