Geometric Nonlinear Static Aeroelastic Characteristics Analysis of High-Aspect-Ratio Wing with Large Deformation

To explore the geometric nonlinearity of high-aspect-ratio wing due to large deformation, the aerodynamics were solved by Navier–Stokes governing equation based on the loose coupling method of CFD/CSD. Considering the large displacement stiffness matrix of wing structure, the Newton–Raphson method is used to solve the nonlinear elastic deformation of the structure. A geometrically nonlinear static aeroelastic coupling calculation program is developed. During the coupling process, an improved elastic approximation method was used to update the aerodynamic mesh, and the data exchange on the coupling interface was realized by a fixed-volume interpolation method. The reliability of the proposed method was verified by HIRENASD wing model. Finally, the effects of geometric nonlinear static aeroelasticity on longitudinal aerodynamic characteristics and stability of swept wing with high aspect ratio at different angles of attack are studied using this method. The results show that the lift direction of a high-aspect-ratio wing is significantly deformed under the influence of aerodynamic loads. The effective angle of attack of the wing decreases with the whole deformation, and the degree of decrease increases from the root to the tip. The significant flexural and torsional deformation will change the lift coefficient and drag coefficient of the wing and reduce the margin of the static stability of the wing.