Reduced-order modeling and aeroelastic analysis of geometrically nonlinear structures of large flexible wings

Geometrically nonlinear aeroelastic problems are key issues in the design of large flexible aircrafts，and accurate modeling of large deformation structures is the basis for geometrically nonlinear aeroelastic analysis. Compared with the nonlinear finite element method，the reduced order model has the advantages of low order and fast solution，but the traditional structural modal modeling method is not applicable to nonlinear structures. For a large flexible aircraft wing，a nonlinear structural reduced-order model is established with the linear structural mode as the base. Nonlinear stiffness coefficients are solved in anon-intrusiveway，and residual basis functions are supplemented to improve the accuracy of structural deformation calculation. The calculation results are in good agreement with the results of the nonlinear finite element method. A geometrically nonlinear aeroelastic analysis framework is established by using the non-planar vortex lattice method，and the geometrically nonlinear static aeroelastic deformation，flutter and gust response are analyzed. The results show that the geometric nonlinear factors have an important influence on the design of large flexible wings，and the aeroelastic analysis method based on the nonlinear structural reduced-order model can take into account the analysis accuracy，computational efficiency，and applicability of complex models. © 2024 Chinese Society of Astronautics. All rights reserved.