ABSTRACT
This chapter presents extensive and a wide variety of results to study the free vibration of specially rectilinear orthotropic: elliptic and circular plates and annular elliptic plates. It discusses the results for elliptic and circular plates and annular elliptic plates with different boundary conditions. Lightweight structures have been widely used in many engineering fields, and hence vibration analysis of differently shaped plates has been studied extensively owing to its practical applications. A vast amount of work has been done for theoretical and experimental results for vibration of orthotropic skew, triangular, circular, annular, and polygonal plates as mentioned by A. W. Leissa. Compared with circular plates, even less work has been carried out for elliptical plates with rectangular orthotropy. The main difficulty in studying the elliptic plates is the choice of coordinates. The reduction method is used to derive an approximate formula for estimating the natural frequencies of orthotropic plates.
