Design and Analysis of a Solar-Power Mini-UAV for Extended Endurance at Low Altitude

Abstract

A solar-powered mini-UAV has been designed for long-endurance performance at low altitude, reflecting practical constraints from preceding experience of authors. The parametric analysis of the solar-power propulsion system is the primary interest of the present study, along with the power requirement estimation of the aircraft design. To cope with the wide range of flight speed, low-Reynolds number airfoils are selected, which possesses low drag characteristics at wide range of angle of attack. Aerodynamic design studies point out that maintaining Reynolds number above 100,000 is a requisite for extended flight operations of the solar-powered mini-UAV. The itemized drag prediction of the UAV design is performed based on the Xflr5 analysis of the UAV configuration. The solar modules and battery systems of the UAV design are represented as equivalent electric models, for the performance simulation of the solar-power propulsion system. Rigorous analyses on the seasonal solar radiation indicate that the capacity of the battery pack should be increased over 50% of the current design to provide continuous operation of the mini-UAV up to 60 days.