Multi-disciplinary Analysis of Solar-Powered Unmanned Aerial Vehicles for Extended Endurance

Drones are extensively utilized in numerous critical applications today, necessitating high flight endurance for many tasks. As a result, solar unmanned aerial vehicles (UAVs) have gained considerable attention from researchers. This study presents the design of two UAVs with distinct wing configurations, both equipped with an equal number of solar cells. A numerical approach is employed to model these UAVs and calculate their aerodynamic coefficients. The power required for sustained level flight is determined using established aerodynamic equations. Additionally, solar cells are simulated in MATLAB/Simulink to investigate the impact of solar radiation on cell output power, current, and voltage. Different locations experience varying levels of solar radiation at specific times of the day, depending on their geographical coordinates and date. Consequently, this research examines the flight endurance of solar UAVs based on flight conditions and solar radiation availability in specific locations. In this paper, two different approaches for calculating the endurance parameter were introduced, and the achieved results are compared. Superior aerodynamic performance and a higher lift-to-drag ratio were observed for the UAV with a high AR. It is seen that reducing weight and distributing the same number of cells across the lower wing surface can significantly enhance flight endurance. In the best possible conditions in the considered place and time, the high AR UAV flies for 10 h and the medium AR UAV flies for 11 h.