Optimum Design of Composite Wing Considering Stiffened Panel Buckling

The present paper treats an optimum design of CFRP stiffened panels under compressive and shear loads. Buckling analysis of stiffened panels is performed by approximate buckling formula on global and local buckling, which is based on the classical lamination theory. First in the present paper, the validity of approximate buckling formula is studied by comparing with the finite element analysis based on the Mindlin plate theory. Next, this approximate analysis technique is applied to a minimum weight design of wing box structures considering stiffened panel buckling. The optimum dimensions of stiffeners and laminate configurations are obtained by using nonlinear optimization technique. The validity of the present optimization approach is examined through the numerical results.