Structure Design And Scale Optimization Of Airfoil Mechanism With Variable Camber

In recent years,with the popularization of UAV and general aircraft,requirements for aircraft performance are constantly improving.As an important part of aircraft,morphing wing has higher requirements on its deformation capacity,bearing capacity,weight and aerodynamic performance.However,flaps and slats are the main forms of wing bending,which have the characteristics of single task and cannot guarantee continuous deformation.In order to solve this problem,a flexible continuous variable camber wing was designed.Then complete Its mechanical modeling and optimize its structure size.Also,verified its aerodynamic characteristics and deformation capacity.Aiming at wide range deformation,determine a wing deformation scheme which contain a flexible trailing edge mechanism and a rigid connecting rod driving mechanism.This mechanism has both the bearing capacity of the rigid mechanism and the large-range deformation capacity of the flexible mechanism.Based on the theory of flexible mechanism,the mechanical modeling of the flexible trailing edge mechanism is carried out,and this mechanical model is verified by finite element simulation.In order to further improve the aerodynamic characteristics of the wing during the cruising and landing stages,a multi-objective and multi-discipline optimization system is established.The lift-drag ratio in cruise stage and lift coefficient in takeoff stage are taken as objective functions.Take NSGA-II multi-objective genetic algorithm as an optimization algorithm,and XFOIL program as a pneumatic solver.Considering the influence of air load on the wing shape,the design variables and boundary conditions are determined and the optimization results are also obtained.After optimization,the aerodynamic characteristics of the wing have been improved.In order to compare the aerodynamic performance of variable camber wing and conventional wing,FLUENT was used to carry out numerical calculation of various aerodynamic characteristics of variable bend wing after deformation.The simulation results show that the lift coefficient and lift-drag ratio of the variable bend wing are higher than conventional wing under the same conditions.