Accession Number : ADA314434

Title :   The Impact of Scales and Spatial Distributions on Small Scale Fluid Loaded Structural Acoustic Models.

Descriptive Note : Final rept. 1 Jun 93-31 Dec 95,

Corporate Author : GEORGIA INST OF TECH ATLANTA SCHOOL OF MECHANICAL ENGINEERING

Personal Author(s) : Cunefare, Kenneth A.

PDF Url : ADA314434

Report Date : 31 DEC 1995

Pagination or Media Count : 35

Abstract : The subject research addressed the scale (dimension) at which an attached structure influences the response of another structure. Here, the attached structures, or features, represent internals of a larger, fluid-loaded structure. Inertial, elastic, and internally wave-bearing structures were considered. The research applied the surface variational principal (SVP) and Hamilton's principal to model the dynamics and acoustics of these coupled fluid-loaded systems. Paradigm structures were a plate in a baffle and a cylindrical shell. A basic function approach was used for representing surface velocities, acoustic pressures, and features. The resulting system of equations then indicated the degree of coupling between features of different scales, and of different scales within a structure. When compared against a point representation, different spatial distribution of the same features were shown to have greatest impact near fluid-loaded resonances. This indicates that greater modeling fidelity is required in such frequency regions. Away from resonances, feature representation had little impact on structural response.

Descriptors :   *ACOUSTICS, *VARIATIONAL PRINCIPLES, COUPLING(INTERACTION), SPATIAL DISTRIBUTION, DYNAMICS, ELASTIC PROPERTIES, SHELLS(STRUCTURAL FORMS), FREQUENCY BANDS, STRUCTURAL RESPONSE, SOUND PRESSURE, ACOUSTIC IMPEDANCE, BAFFLES.

Subject Categories : Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE