Optimal design of rectangular composite flat-panel sound radiators considering excitation location

Abstract

The optimal excitation locations of rectangular composite sound radiation plates to produce relatively smooth sound level pressure (SPL) curves are determined using an optimal design method. In the optimal design process, the vibration of the plate is analyzed using the Rayleigh-Ritz method, the sound pressure produced by the plate is calculated using the first Rayleigh integral, and the optimal excitation location is determined using a global optimization technique. The experimental SPL curves of several sound radiators were measured to verify the accuracy of the theoretical predictions. In the determination of the optimal excitation location, the trial radius of the circular excitation force is used in the vibro-acoustic analysis to predict the theoretical SPL curve of the plate, a SPL discrepancy function is established to measure the sum of the squared differences between the SPLs at the chosen excitation frequencies and the average value of such SPLs, and a global minimization technique is used to search for the best estimate of the radius of the circular excitation force by making the SPL discrepancy function a global minimum. The optimal excitation locations of several composite sound radiators with different aspect ratios and layups are determined using the proposed method. (C) 2013 Elsevier Ltd. All rights reserved.