Aerolelastic Analysis of a Thin-Walled Composite Aircraft Wing With an External Store Subjected to a Follower Force

Abstract

This study reports dynamic aeroelastic analyses of an aircraft wing with an attached mass subjected a lateral follower force in an incompressible flow. A swept thin-walled composite beam with a biconvex cross-section is used as the structural model that incorporates a number of non-classical effects such as material anisotropy, transverse shear deformation and warping restraint. A symmetric lay-up configuration i.e. circumferentially asymmetric stiffness (CAS) is further adapted to this model to generate the coupled motion of flapwise bending-torsion-transverse shear. For this beam model, the unsteady aerodynamic loads are expressed using Wagners function in the time-domain as well as using Theodorsen function in the frequency-domain. The flutter speeds are evaluated for several ply angles and the effects of follower force, transverse shear, fiber-orientation and sweep angle on the aeroelastic instabilities are further discussed.