Abstract
A method of analysis is presented for determining the free vibration frequencies of twisted 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, a method of Ritz is used to derive a frequency equation where in the displacement functions are modified to accommodate arbitrary sets of edge conditions for both in-plane and out-of-plane motions. In numerical examples, natural frequencies and mode shapes are presented for a wide range of geometric parameters, and the maximum fundamental frequencies are determined by the LO design approach.
