On the Modeling of Coupled Vibration of Rotating Thin-Walled Closed-Section Composite Beams

The free vibration model of a rotating composite thin-walled closed-section beams is presented in this paper. The two-dimensional cross-sectional analysis based on the variational-asymptotical method(VAM) is combined with the Hamilton’s principle to derive the equations of motion and associated boundary conditions of the beams. The Galerkin method is employed in order to solve the coupled differential equations. The natural frequency results obtained for the present model are compared with those of the existing models. Numerical results are obtained for the laminated composite cantilevered box beam with Circumferentially Uniform Stiffness(CUS) configuration, the effects of the fiber orientation, pitch and precone on the natural frequencies associated with coupled vibration modes are investigated.