Dynamics of Thin-Walled Composite Aircraft Wings Carrying External Stores

Abstract

In this paper, the free vibration and dynamic response to external time-dependent loads of aircraft wings modeled as thin-walled anisotropic composite beams and carrying eccentrically located heavy stores are analyzed. In this context, bending-twist coupling induced by both the eccentric heavy stores distributed along the wing span and chord, and by the anisotropy of the wing material, that is essential when dealing with aircraft wing problems was included . In addition to the anisotropy of constituent materials, also transverse shear and warping restraint effects have been incorporated. The governing equations of the wing-store system and the related boundary conditions are derived via application of Hamilton's Principle. To solve the eigenvalue/boundary problems, the Extended Galerkin Method (EGM) is applied. Numerical simulations highlighting the implications of external stores coupled with the implementation of the structural tailoring technique on eigenfrequency and dynamic response to external time-dependent loads are supplied, and pertinent conclusions are outlined. Nomenclature ij a = 1-D global stiffness coefficients i b = mass terms L = wing semi-span i Z ,ηi = the i-th mass location along the wing span and its dimensionless (≡ Zi/L) counterpart i m , i m = mass of the i-th store and its dimensionless (≡ mi/mw) counterpart θ = ply angle i r , i r = the offset between the centroid of the i-th store and the central line of the clean wing, and its dimensionless (≡ ri/L) counterpart