5aSA3. Fluid-loaded plate coupled to a distributed inhomogeneity---Review.

Session: Friday Morning, May 17

Time: 9:05

Author: Joseph. M. Cuschieri
Location: Dept. of Ocean Eng., Florida Atlantic Univ., Boca Raton, FL 33431
Author: David Feit
Location: David Taylor Res. Ctr., Bethesda, MD 20084


The problem of scattering from a fluid-loaded plate structure coupled to a distributed inhomogeneity is considered. Results have been presented which include the plate surface velocity Green's function, the far-field and near-field scattered pressure, and the acoustic and structural intensity. The distributed inhomogeneities considered varied both in type (mass or stiffness) and shape. In all instances, the perturbation due to the inhomogeneity, relative to the elastic characteristics of the plate, is small. In the case of shape variations, the influence of ``smoothness''at the edges of the inhomogeneity, and of oscillations within the inhomogeneity distribution were also considered. In this presentation, the results that have been generated thus far, will be reviewed and general conclusions drawn from these results. It is shown that depending on the frequency range of interest, the results can be significantly influenced by the shape and type of inhomogeneity. Stiffness inhomogeneities, in general, are less significant compared to mass inhomogeneities. However, in relative terms, internal variations in the inhomogeneity shape are more significant for stiffness inhomogeneities than for mass inhomogeneities. Alternate forms of presenting the results will be explored. [Work sponsored by ONR.]

from ASA 131st Meeting, Indianapolis, May 1996