SUPERSONIC FLUTTER ANALYSIS OF COMPOSITE PLATES AND SHELLS

A high-precision doubly curved quadrilateral thin shell finite clement is used for studying the supersonic flutter behavior of laminated com posite plates and shells. The composite material property is included using classical lamination theory, and the supersonic aerodynamic effe ct is included using linearized piston theory. To reduce the number of degrees of freedom of the finite element aeroelastic system, the norm al modes approach is adopted. Results are presented to illustrate the behavior of flutter characteristics for composite plates and curved pa nels, and composite cylindrical and conical shells. Parametric studies concerning the effects of boundary conditions, fiber orientation, deg ree of orthotropy, and flow angle on the flutter characteristics are p resented for a series of selected examples. The accuracy, efficiency, and applicability of the present finite element method are demonstrate d by illustrative examples, and, whenever possible, the results are co mpared to alternative solutions available in the literature.