Aeroelastic Response Analysis of Composite Blades Based on Geometrically Exact Beam Theory

The geometrically exact nonlinear beam theory consisting of the latest version of two-dimensional variational asymptotic beam sectional analysis (VABS) and one-dimensional geometrically exact beam theory (GEBT) has been widely used for the structural analysis of composite beam structures. The theory can be used for establishing the aeroelastic model of composite blades undergoing large deflections to improve computational accuracy and efficiency. In this paper, the theory has been extended from structural analysis to aeroelastic analysis of blade, and an accurate and efficient method for aeroelastic response analysis of composite blades has been presented based on the theory and unsteady aerodynamic model. The geometrically exact nonlinear equations of motion and the latest VABS are used to deal with one-dimensional beam analysis and the structural property of blade cross section, respectively. The Peters-He finite state dynamic wake model and the Peters finite state airloads theory are used to calculate the induced velocity and blade airloads, respectively. The presented method has been used to analyze the aeroelastic responses of composite blades, and its accuracy has been verified by experimental data. The influence of transverse shear deformation on the aeroelastic response of composite blades was also investigated, indicating that the transverse shear deformation has a nonnegligible effect on aeroelastic response analysis of hingeless composite rotors in hover.