Research On Aeroelastic Tailoring Of High Aspect Ratio Composite Wing

The concept of "green aviation" has established specific design objectives for aircraft that prioritize both economic and environmental considerations.This has led to increased demands for improved structural performance and material advancements in future aircraft development.The utilization of composite materials in aircraft design can lead to a significant reduction in weight,resulting in fuel savings and increased flight range.Additionally,the stiffness designability of composite materials can aid in controlling the elastic deformation of the wing and improving the structural performance of the aircraft.In recent years,composite materials have emerged as a promising solution for designing aircraft wing structures in order to achieve the engineering concept of "green design".Compared to traditional metallic wings,high aspect ratio composite wing structures are more flexible and susceptible to larger bending and torsional deformations under aerodynamic loads.This results in serious geometric nonlinear aeroelastic problems,making static aeroelastic effects such as bending and torsion of high aspect ratio ratio composite wings more complex than those of general wings.This dissertation aims to explore the aeroelastic shear design laws for high aspect ratio composite wings in order to enhance the performance of aircraft.Conducting research on aeroelastic shear design is crucial for achieving this goal.The main focus of this dissertation includes the following research work:1.A static aeroelastic time domain simulation method for high span ratio composite wings is established based on the loose coupling theory considering the geometric non-linear effects of the flexible structure.The solid shell unit is selected as the basic numerical simulation calculation unit of the composite laminate,and the feasibility and effectiveness of this numerical calculation method is verified by using the standard model DLR-F6 wing-body fusion as the research object.2.The design scheme of unbalanced coefficient of carbon fiber composite laminate is defined,and four types of composite skin layups,such as equal thickness,variable thickness,variable angle and variable area,are constructed on this basis.Finally,numerical simulations are carried out for high span ratio composite wing based on the above four typical layup schemes to study the relationship between laminate unbalanced coefficients and static aeroelastic properties under different layup methods.3.The mathematical equation model for the variation of the reference direction of the ply fibre plane is studied,and a finite element model for the variation of the reference direction of the ply fibre plane is constructed to analyse the relationship between the variation of the reference direction of the ply fibre plane and the static aeroelasticity.The focus is on the effect of the angle of the reference direction of the lay-up fibre plane on structural deformation,stress and strain,as well as the effect on the pitch moment,drag and lift of the wing during the redistribution of aerodynamic loads.