Nonlinear Aeroelastic Analysis Of High-Aspect-Ratio Wing Based On ONERA Aerodynamic Model

The high-aspect-ratio composite wing is generally used in high-altitude long-endurance UAV,which will produce large deformation under unsteady aerodynamic force,resulting in serious nonlinear aeroelastic problems.Nonlinear aeroelastic analysis is becoming one of the research hotspots at home and abroad.In this paper,the nonlinear aeroelastic response of a high-aspect-ratio wing is studied.Peters finite state theory and dynamic inflow theory are introduced to replace the linear aerodynamic equations in the classical ONERA model.The nonlinear aerodynamic equation of ONERA model is improved to make it more stable at high angle of attack.The two-dimensional dynamic stall aerodynamic model for the morphed airfoils is obtained by transforming the curve deformation function into the generalized coordinates.With the experimental model of Tang and Dowell,the second order nonlinear differential equations of wing with a tip mass are derived by using Hamilton principle.The aeroelastic equations of the high-aspect-ratio wing are established by combining this equation with the modified ONERA aerodynamic model.The small disturbance analysis method and time integration method are used to solve the nonlinear modal equations to obtain the nonlinear flutter boundary and response curve of the wing.The range and amplitude of the limit cycle are determined.The calculation results are in good agreement with the test results.At last,the influence of aileron deflection angle on wing flutter speed is studied,and the limited influence on wing flutter speed is found,and the reason is analyzed.