Aerodynamic Performance Of The Dragonfly Corrugated Wings In Gliding Flight

The micro-flapping-wing aircraft has the characteristics of small size,light weight,excellent stealth performance and strong operability.As a brand new aircraft design structure,it can not only take off and land vertically and accelerate in almost any direction like a micro-rotor aircraft,but also can maneuver precisely at high speed and long-distance cruising like the micro-fixed-wing aircraft.Dragonfly is the most suitable bionic object for the micro-flapping-wing aircraft because of its excellent flight ability.Due to the advances in computational fluid dynamics(CFD)and experimental techniques,researchers are beginning to study the aerodynamic performance of the dragonfly wings.However,there are few studies about the aerodynamic performance of forewing–hindwing interaction in gliding flight.To explore the aerodynamic influence of the corrugations and flexibility on dragonfly wings,the CFD models of three-dimensional corrugated dragonfly forewing and hindwing were established by software CATIA based on the current research.The main research contents are as follows:In order to study aerodynamic performance of the dragonfly hindwing at gliding flight at different Reynolds numbers,this paper studied aerodynamic effects of corrugation at gliding motion using the method of CFD.Numerical simulation indicates that the effect of corrugation is to increase both lift and drag to varying degrees,and the aerodynamic effect of wing corrugation might be Reynolds numbers dependent.To reveal the effect of the aerodynamic performance of dragonfly forewing –hindwing interaction at gliding motion in different situations,this paper studied the aerodynamic effects of dragonfly forewing–hindwing interaction at gliding motion in different situations using the method of CFD.the results show that the interactions between forewing and hindwing enhance the aerodynamic performance of both forewing and hindwing to varying degrees compared to independent wings,especially the effect of forewing is more evident at small angle of attack.The aerodynamic performance of dragonfly forewing–hindwing interaction significantly enhanced as the speed of gliding increases,and gradually decreases with the increase of the distance between the wings.