ACOUSTIC HARMONIC RADIATION FROM FLUID-LOADED INFINITE CYLINDRICAL ELASTIC SHELLS USING ELASTICITY THEORY

The problem of acoustic harmonic radiation from a fluid-loaded infinite cylindrical elastic shell subjected to arbitrary loading is addressed using three-dimensional elasticity theory. The classical integral transform technique is used to derive a formal expression for the radiated pressure in the fluid. This expression is then evaluated for the observation point in the far field using the standard stationary phase method. The general formulation is then applied for a special case of a fluid-loaded shell excited by a harmonic ring drive. Numerical results over a wide range of parameters are presented for the far-field directionality patterns for a steel shell immersed in water. The results are presented as a function of the excitation frequency of the ring drive, the relative thickness of the shell, and the circumferential mode number. The characteristics of the directionality patterns are then related to the wave field on the shell-fluid interface.