Accession Number : ADP003713

Title :   Modeling the Relation between Structural Vibrations and Radiated Sound,


Personal Author(s) : Vandeponseele,P. ; Snoeys,R.

Report Date : 1984

Pagination or Media Count : 13

Abstract : Two computational methods for estimating the sound power radiated by mechanical structures are presented. The reported technique fills in the gap between structural vibrations and radiated sound, and enables already in the design stage, accurate assessment of noise reduction measures. Both methods which are based upon a Helmholtz integral formulation, require the knowledge of the geometry and the modal characteristics of a structure's vibrating surfaces, so that the pressure on the surfaces can be computed. The first method is limited to flat surfaces and replaces the original source by a distribution of point sources which are easy to integrate over the radiating surface. The second method is more general and accurate but requires considerably more computing time since it includes a closed form integration of the associated surface integrals. This paper reviews some principles on acoustic radiation, the concerned algorithms are briefly commented and verification experiments, where close correlation was found between predicted and experimentally determined sound power levels, are presented. (Author)

Descriptors :   *Structural mechanics, *Mathematical models, *Noise reduction, Machinery noise, Computations, Vibration, Acoustic waves, Algorithms

Distribution Statement : APPROVED FOR PUBLIC RELEASE