Maximizing the fundamental frequency of laminated cylindrical panels using layerwise optimization

A method of analysis is presented for determining the free vibration frequencies of cylindrically curved laminated panels under general edge conditions, and is implemented in a layerwise optimization (LO) scheme to determine the optimum fiber orientation angles for the maximum fundamental frequency. Based on the classical lamination theory applicable to thin panels, a method of Ritz is used to derive a frequency equation wherein the displacement functions are modified to accommodate arbitrary sets of edge conditions for both in-plane and out-of-plane motions. The LO approach, a recently developed scheme for laminated plates, is extended for the first time to the optimum design of curved panels. In a number of numerical examples, the accuracy of the analysis and the effectiveness of the LO approach are demonstrated.