Modeling And Dynamic Characteristic Research Of Combination Wing Variable Sweep Aircraft

The variable-sweep aircraft can meet the different aerodynamic parameters of the aircraft at high,medium and low speeds by controlling the change of the sweep angle and aspect ratio.However,after the wings of the traditional variable-sweep aircraft are unfolded,a triangular vacant area will be left between the fuselage and the fuselage,which will affect the aerodynamic performance;the wing adopts an external design,and it is impossible to change the wing area(or change the amplitude extremely)while changing the sweep.At the same time,the drive transmission structure is cumbersome and requires a great price in weight and reliability.In response to the above problems,the following research work is carried out in this paper:Firstly,the deficiencies of the existing technical solutions are analyzed,and the solution of the combined wing variable swept is proposed in a targeted manner.Through the casing structure,the change rate of the wing area before and after deformation is increased,and the space after the wing is deployed is supplemented by the auxiliary wing.It plays the role of supporting the main wing and increasing the rigidity of the wing structure;on this basis,the selection design of the variablesweep drive transmission structure is carried out.The transmission scheme of the wing is designed,and the transmission mechanism of the aileron is designed to realize the slit storage of the aileron.The aerodynamic modeling and aerodynamic parameter analysis of the combined wing variable-sweep aircraft with different sweep angles are carried out respectively.The calculation shows that: the aircraft can reduce the wing sweep angle to obtain a higher lift coefficient at low speed;high Mach number When the aircraft increases the wing sweep angle,better aerodynamic performance can be obtained.Then,the flutter analysis was carried out for the wing of the combined wing variable-sweep aircraft,and the finite element model of the wing with different sweep angles was established,and the modal analysis was carried out,and the finite element model was verified by modal test;Nastran was used to verify the finite element model.The flutter analysis of the wing was carried out,the flutter speed was calculated,and the flutter speed of the combined wing was verified.It was calculated that the flutter speed was not reached in the fully deployed state,and the combined wing was safe.The swept action realizes the function of flutter suppression.Then,it is proved by finite element calculation that the auxiliary wing can effectively improve the structural strength of the main wing;the dynamic characteristics of the auxiliary wing are analyzed by Adams,and the kinematic auxiliary load is calculated;It is found that when considering the elastic deformation of the connecting rod,the transmission error of the main wing is within 0.5°,and the error is within the allowable range;when the hinge clearance e=0.5mm,the limit transmission angle β=8.8°,which is less than the actual transmission angle of the connecting rod 9.87°,there will be no jamming.Finally,through the similarity criterion,the variable-sweep drive transmission performance test prototype was developed by taking the scaling factor as 1/2,and the related performances were tested,including the deformation parameters,static and dynamic load capacity,auxiliary wing of the variable-sweep drive transmission performance test prototype.Folding function,etc.,all parameters are up to standard,which proves that the selection and design of the variable-sweep drive transmission scheme is reasonable,and the design of the auxiliary wing transmission scheme is feasible.To sum up,by analyzing the shortcomings of the existing schemes,this paper proposes a scheme of changing the sweep of the combined wing,and conducts modeling to study its aerodynamic performance,and conducts modeling and flutter analysis for the combined wing,which verifies that the combined wing is safe.The selection and design of the combined wing variable swept drive transmission scheme and the aileron transmission scheme are carried out,and the simulation and test prove that the selection design is reasonable and the aileron transmission scheme is feasible.