Experimental studies on the in-plane vibrations and sound radiation in an annular thick disk

A study was conducted to demonstrate experimental investigations on the in-plane vibrations of thick plates with non-uniform boundary conditions. The natural frequencies of an annular disk supported at one point were measured and compared with values measured for free support conditions. The Rayleigh-Ritz method was used to demonstrate the use of boundary characteristic orthogonal polynomials as admissible functions in a three dimensional analysis to obtain the natural frequencies and the associated mode shapes analytically. The free in-plane vibration of the disk was assumed to have sinusoidal variations along the circumferential direction of the disk.