Acoustic radiation from plates driven by multiple point random forces

Abstract

The problem of acoustic radiation from plates driven by multiple random point forces is analyzed in this study. First, the formulation of the sound power radiated by infinite thin plates (one dimension) under the action of multiple random point forces is derived. The reaction of the acoustic medium on the vibratory response of plates is taken into account. With the input spectrum being assumed as bandlimited white noise, the effects of input force correlation on the radiated sound power level are examined. The analysis is then extended to finite thin plates with four simply supported edges. The fluid loading effects are neglected. The exact expressions for the surface acoustic intensity and the radiated sound power are also derived. Assuming light damping, approximate solutions for acoustic intensity and sound power are obtained. An experimental study is carried out to measure the surface acoustic intensity patterns and compare with the analytical results. The effects of input force correlation on the acoustic intensity patterns and the sound power level are discussed.