David C. Ricks
Henrik Schmidt
Dept. of Ocean Eng., MIT, Cambridge, MA 02139
A fluid-loaded cylindrical shell is modeled with the full equations of elasticity. The model is excited by time-harmonic ring forces that can push in the radial, circumferential, and axial directions. The ring forces can have a linear phase shift around the circumference of the shell, so helical waves can be excited and studied for any circumferential order. This ``full elastic'' model serves as a reference model to check the accuracy of the Donnell ``thin shell'' equations. When identical shells are excited by identical ring forces, the ``full elastic'' and ``thin shell'' models exhibit the same modes of wave propagation, with slightly different amplitudes of response. However, in some cases, the wave speeds are very different. The significance of these differences is being evaluated. [Work supported by ONR.]