Li Dichen*，Yang Long，Wei Chuang，Zhang Tiejun
Aeronautical Science and Technology Key Lab for High Speed and High Reynolds Number Aerodynamic Force Research，CAE Aerodynamics Research Institute，Shenyang 110034，China
Abstract: The solar-powered HALE UAV usually use low Reynolds number airfoil, and its day-night flight state is different. Based on surrogate model optimization design method, and a steady RANs solver coupled with the grammatheta transition model validated by wind tunnel experiment data, a multi-point aerodynamic optimization design method, by which weight distribution is based on drag power consumption under different flight states, was proposed. In view of typical low Reynolds number airfoil E387, four design states: night cruise, morning climb, day cruise and evening descent optimization were carried out. The results show that the power indices of the four design states are increased by 7.84%, 7.95%, 11.34% and 6.98%, respectively, which improves its day-night flight aerodynamic performance.
Key Words: solar-powered UAV; low Reynolds number airfoil; surrogate model; transition model; multi-point optimization