Design Of Dragonfly-like Wing And Research On Its Aerodynamic Characteristics

Flapping Wing Micro Air Vehicle(FWMAV)is a new type of micro aircraft that imitates the flight movements of insects or birds in nature,with the advantages of small size,light weight,strong maneuverability and low cost,so it has broad application prospects in the military field and civilian field.However,the lack of endurance caused by its low energy utilization has caused great trouble to researchers.As one of the key structures in the aircraft to generate liter thrust,the geometry and movement of the wing have a great impact on flight efficiency.Among the many flying insects,dragonflies have fast flight speed,strong flexibility and mobility,and have developed into one of the most stable flying organisms in nature,so this paper takes the forewing of dragonflies as the bionic object to study the influence of morphological characteristics on the aerodynamic properties of the wings,and on this basis,a biomimetic wing with good aerodynamic characteristics is designed.First,the morphology and kinematics of dragonfly wings were studied.The flight mechanism of the dragonfly was explained based on the insect high-lift mechanism,and the kinematic model was established by capturing the flexible deformation and overall motion of the dragonfly’s wings in a fixed space with a high-speed camera,based on which the wings were placed in an inertial coordinate system;the geometric parameters of the dragonfly’s wings were measured by various mathematical methods to determine their basic size,weight,and area distribution.Some basic conformational features possessed by the wings were analyzed by macroscopic observation and microscopic observation.Secondly,the effects of different features on the aerodynamic performance of the bionic wing are investigated.The process of numerical simulation of the wing model by computational fluid dynamics method is introduced,and the numerical simulation of planar rigid wing aerodynamic performance is carried out to verify the feasibility of the method;on this basis,the effects of planar shape,mesh distribution and airfoil fold structure on the aerodynamic performance of the bionic wing are investigated respectively,and the results show that the planar shape has a large effect on the aerodynamic performance of the wing,different airfoil fold structures The results show that the plane shape has a large influence on the aerodynamic performance of the wing,the different airfoil pleat structure also has a certain influence,and the mesh distribution has almost no influence.Then,the bionic wing was designed and fabricated,and its aerodynamic performance was analyzed.Based on the study of the factors affecting the aerodynamic performance of the wing,the results of the comprehensive analysis,the dragonfly bionic wing was designed and its aerodynamic performance was verified by numerical simulation;then the wing vein and the wing membrane were processed and the actual wing model was made.Finally,an experimental verification of the physical wing is carried out.A flutter device with three degrees of freedom is designed,a wing aerodynamic testing experimental system is built,and the magnitude of aerodynamic forces generated during the physical motion of the bionic wing is measured in a wind tunnel environment,which is compared with the simulation results with good agreement and illustrates the feasibility of the design of this paper.