TRANSVERSE VIBRATION OF A QUARTER OF AN ELLIPTIC PLATE WITH VARIABLE THICKNESS

Rayleigh-Ritz method has been used to find the first three frequencies and mode shapes for free flexural vibration of a plate in the form of a quadrant of an ellipse with linear and quadratic thickness variatio ns. The results for a quarter of a circular plate with uniform thickne ss have been obtained as a special case and comparison has been made w ith results already available. By taking various combinations of clamp ed, simply-supported and completely-free edges we get twenty-seven dif ferent cases. Tables are given for the first three frequencies for dif ferent values of parameters. Mode shapes have also been plotted in som e cases. The convergence of results is indicated by working out approx imations of various orders.