基于动响应数据的大柔性机翼结构降阶方法

Due to the flexibility of modern aircraft wing, geometric nonlinearity cannot be neglected. Based on dynamic response data samples, non-linear stiffness coefficients in structural dynamics equation are identified based on harmonic balance and fast Fourier transform, and a non-linear structural order reduction model is established. The basic mode of displacement residue is introduced to recover the displacement of large flexible wings. A geometrically nonlinear aeroelastic analysis framework for large flexible wings is established by combining non-planar vortex lattice method and non-planar spline interpolation method. Compared with reduced order model for the traditional geometric nonlinear structure based on static data regression analysis, the proposed method requires a small number of load sets and improves analysis efficiency. Results show that compared with the nonlinear finite element method, the proposed model has high accuracy and can be effectively applied to the geometric nonlinear static aeroelastic analysis of large flexible wings. The result of traditional linear calculation method is significantly different from that of the nonlinear method.