Aeroacoustic and aerodynamic measurements of a ducted propeller

The flexibility and wide range of possible applications in both civilian and military areas make unmanned aerial vehicles (UAVs) an object of continuous research. An important focus of such work is the propulsion system and ways of improving its efficiency. A ducted propeller is a common solution to increase the thrust and power efficiency of the propulsion system, which is especially beneficial for UAVs driven by electric motors due to their limited battery capacity; however, noise created by UAVs can not only annoy the public but may also reduce its acoustic stealth. Hence, the aim of this paper is to describe a test rig that can take aeroacoustic and aerodynamic measurements of both ducted and open propellers and present some initial experimental results. Both aeroacoustic and aerodynamic measurements were taken in an anechoic chamber with an arc of 6 ½ in. microphones to record noise level from different directions. The APC 12 × 8 propeller was used together with the SunnySky x2820 brushless motor.