Design and Development of Electric Ducted Fan for Small UAVs

Abstract

Green energy is under the spotlight in this decade. Major world technologies are shifting

from conventional fossil fuels to green energy. To shift from conventional fossil fuel en- gines to electric propulsion the surge in the demand for highly efficient propulsive units

increases. Electric ducted fan solves this problem by providing high propulsion in a compact design with other benefits like thrust vectoring. Therefore, this study discusses the analytical technique used in designing ducted propellers. After modeling, a CFD simulation is performed to verify the initial design. After the initial design, optimization is done to improve the overall performance characteristics of the ducted fan. Different

approaches are explored for designing the electric ducted fan. The theoretical calcu- lation is done for the initial design specification and blade characteristics. An Electric

Ducted Fan (EDF) with a Diameter of 120mm designed for 19N thrust is proposed using analytical calculations. For 19N thrust duty points total pressure difference of 2500Pa is proposed with 0.5m3/s flow rate avoiding the stall region. Theoretical 80% efficiency is proposed on these duty points. Due to the high-pressure difference, a high solidity ratio is selected. The cascade approach is used to select the blade characteristics. A procedure is verified using Numerical simulations to validate the design procedure. Overall 78% efficiency is achieved on 0.5m3/s having a 2551 Pa pressure difference. Optimization is done to increase overall efficiency and to increase thrust. Kriging Response surface

proposed design parameters verified using Numerical simulation, which shows a 3 per- cent efficiency improvement. The final design is 3-D printed with further addition of a

stator to perform experimental validation of the design process and its integration in Unmanned Air Vehicles (UAV) and Micro Aerial Vehicle (MAV), having a wide variety of applications in different sectors like defense and smart agriculture. Experimentation thrust shows an excellent agreement with numerical simulations of the proposed final design. Overall, 19N thrust is achieved in experimentation testing of developed EDF.