An Analytical-Numerical Coupled Model for an Aeroelastic Analysis of Tail Flutter Based on Bending-Torsional Coupling

The aeroelastic instability is the mutual interaction of aerodynamic, structural, and inertial forces that can cause the flutter in aircraft structures. In this research, applying the coupling of a flutter with two degrees of freedom and the finite-element method, to a symmetric airfoil section of an aircraft tail, the flutter speed is investigated. The geometry and thickness of tail skin and isotropic and layups of composite materials are effective parameters of the torsional and bending stiffnesses of the airfoil section studied using the finite-element method. Lagrange's equation is used to analyze the aeroelastic instability of the tail. Finally, the impact of the effective parameters on the flutter speed and instability of tail are discussed. The results obtained show that, at the same thickness, the flutter speed of angle-ply layups is higher than of quasi-isotropic composite laminates.