Abstract: In order to study the drag reduction characteristics of different winglets, four types of winglets and winglet extensions are selected as the research objects. Under the same extended winglet and medium-high speed flight conditions (Ma = 0.6), five different winglet devices are numerically simulated using the k-ω SST (shear stress transfer) two-equation model. The pressure characteristics of the wing surface and the winglet flow field of five types of winglet are studied. The drag reduction characteristics of different winglet are compared and analyzed, along with the principle of induced drag changes. Research results show that the airflow guidance direction of different winglets the surface flow field of the wing and affects the winglet pressure distribution; under the conditions of medium-high speeds and with same wing length, the fused and raked winglets have better drag reduction effect, and the double-feathered winglet can effectively disperse the winglet vortex.

Key words: winglets, k-ω SST two-equation model, drag reduction, lift-to-drag ratio, flow field