Nonlinear aeroelastic analysis of a composite wing by finite element method

Abstract

The aim of this paper is to develop a modified 1D structural dynamics model for aeroelastic analysis of a composite wing under large deformations. To attain this goal, an accurate available mechanical beam model of a composite wing was considered and improved to simulate large deformation behavior. Also, in aerodynamic aspect of view, a semi-experimental unsteady aerodynamic (ONERA dynamic stall) model has been incorporated to construct the aeroelastic model. To set up a flutter determination tool based on the eigenvalue analysis, Finite Element Method (FEM) has been implemented to discretize the aeroelastic equations. Also, a finite element cross-sectional analysis code VABS (Variational Asymptotical Beam Sectional Analysis) has been applied to determine composite cross-sectional properties across the wing span. Because of the existence of nonlinear terms in the aeroelastic equations, due to the large deformation behavior, the perturbed dynamic equations have been established about the nonlinear static equilibrium to capture the flutter boundaries. The obtained results are in good agreement with the available experimental data. It is found that the present aeroelastic model is appropriate for analysis of composite wings with arbitrary cross-sections.