Comparative study on the aerodynamic characteristics of various wingtips for soaring drones

The bionic structure of birds is an important topic in aircraft research, and determining the configuration of wingtips is important. The wingtips of birds have two characteristics: upturned and slotted. Many studies have shown that these wingtip characteristics can improve aerodynamic efficiency, but the wing models, calculation contents, comparison objects, and applicable scenarios used in these studies differ, and the conclusions also differ. To explore wingtip forms suitable for soaring drones, model building, aerodynamic characteristic calculations, and a comparative analysis of various wingtips are presented in this paper. This research is based on a fixed-wing drone that mimics soaring birds, such as eagles and vultures, using thermal updrafts to soar for long periods. Two wingtip models, the seamless wingtip and biomimetic slotted wingtip, were established. The aerodynamic characteristics of the wingtip models were calculated and compared under various cant angle states. The results show that in most flight states of fixed-wing soaring drones, seamless wingtips have higher lift coefficients, lower drag coefficients, and higher lift-to-drag ratios than bio-memetic slotted wingtips, making them more suitable for the soaring drone design.