Large amplitude vibration of orthotropic sandwich elliptic plates

The present paper deals with non-linear vibration of sandwich elliptic plates of uniform thickness made of orthotropic material. The governing partial differential equations are deduced by the method of ‘constant deflection contour lines’ proposed by Mazumder. The time dependent non-linear differential equation has finally been solved. The graphs corresponding to the ratio of non-linear to linear frequencies versus non-dimensional amplitude are drawn for movable as well as for immovable edge conditions and for different aspect ratios and compared with the existing results.