Technical Development of Radiated Noise Reduction Using Sensitivity Analysis : Series C : Vibration, Control Engineering, Engineering for Industry

As engine block vibration contributes to engine noise, reducing the noise it readiates has become a major theme. Recently, radiated noise has been calculated on the basis of structural vibration data using BEM. Although there have been reports on radiated noise calculations, no literature reporting investigations of structural changes to reduce radiated noise has appeared. In this study, we investigated the basis of BEM to calculate radiated noise. We applied FEM to a rectangular panel model to analyze its vibrations. Using BEM we calculated the radiated noise from this vibration data. Next, in order to find a method for making structural changes, we applied the eigenmode sensitivity analysis method proposed by one of the authors. As a result we were able to reduce the noise pressure level radiating from the rectangular panel.