Annular winglet of civil airliner wing

Belonging to the aerial pneumatic technical field, the invention discloses an annular winglet of a civil airliner wing. The annular winglet comprises an outer ring section, an inner ring section and a transition section. The tip of the inner ring section is in fixed connection with the tip of the outer ring section, and the root of the inner ring section and the root of the outer ring section areconnected and are fixed between an upper and a lower flake structures of a transition section through rivet joint, so that the inner ring section and the outer ring section can be connected into an integral ring structure, and the wing tip of an airplane wing is also placed between the upper and the lower flake structures. The annular winglet of a civil airliner wing in the invention has an annular structure, and has greater effective spread length effect than routine winglets under the condition of a same geometric wing spread length increment, thus being able to reduce induction resistance.Two ends of the annular winglet are closed into rings, and the intensity and rigidity are both improved substantially, so that the structural weight can be reduced. With strong anti-torsion and anti-bending properties, the annular winglet provided in the invention has small influence on airplane flutter speed.