Effect of additional boundary conditions on the axisymmetric free vibrations of oblate spheoidal shells

الملخص EN

This research deals with the effect of using additional boundary conditions as well as the eccentricity ratio on the axisymmetric free vibrational characteristics of thin isotropic oblate spheroid shells.

The formulation depends on the boundary matching method using the non – shallow shell theory.

The oblate shell was assumed to be constructed from two spherical elements matched along the continuous boundaries.

The additional boundary conditions under construction were clamped – clamped, clamped – free and pined – pined.

It was found that the natural frequency of the shell with clamped – clamped additional boundaries was greater than other two types of the additional boundaries.

On the other hand it was found that in the case of clamped – clamped boundary condition, the eccentricity ratio has an effect on the natural frequency greater than the other two cases, i.e, clamped – free and pined - pined cases, respectively.