A design approach for minimizing sound power radiation from vibrating
thin shell structures is presented. The method couples finite element
analysis for determining structural modes and vibrations with a bounda
ry element/wave superposition code for determining sound power radiati
on. Noise reduction is accomplished herein by optimal placement and si
zing of small point masses on the structure. These masses alter the cr
itical mode shapes so as to reduce sound power. The simulated annealin
g technique is used to determine the location and/or magnitude of the
point masses. A computer program has been developed for design. Design
examples are presented with the use of the computer program.