Steven R. Hahn
Dept. of Mech. Eng., Georgia Inst. of Technol., Atlanta, GA 30332
It is currently possible to analyze the acoustic radiation and scattering from submerged elastic structures in the low to moderate ka range. However, in the mid- to high-frequency range, tradition techniques, such as finite element/boundary element (FE/BE) methods, have failed to yield reliable results. One reason for the poor performance of such computational techniques, in the mid- to high-frequency range, is sensitivity to structural detail. Here, a method is presented that calculates sensitivities to structural changes. The technique uses perturbations to pre-existing structural-acoustic models. The sensitivity data can be used to indicate areas where attention to detail should and should not be placed, leading to a more efficient mesh refinement process. It can also be useful for more efficient reanalysis and optimization. The analysis presented is based on, but not limited to, FE/BE models. Several numerical examples are presented that illustrate the calculation of the sensitivities and how they can be used for design optimization and model refinement.