DESIGN FOR A HIGH-EFFICIENCY SOUND SOURCE BASED ON CONSTRAINED OPTIMIZATION PROCEDURES

In this paper, optimal control theory is applied to the problem of max imizing the power-conversion efficiency of a circular source in an inf inite baffle. The first section of the paper is devoted to demonstrati ng that constrained optimization procedures, when applied to a circula r source undergoing centrally symmetric vibrations, yield a solution f or a transverse velocity profile which maximizes the radiation efficie ncy of the source at a specific frequency. The velocity distributions that produce the maximum possible radiation efficiency of a circular r egion are shown for several frequencies. In the second section of the paper, it is shown that the velocity profiles corresponding to the eig enfunctions of a circular plate of uniform thickness fortuitously prod uce the maximum possible radiation efficiency a certain frequencies. F inally, the power-conversion efficiency of the circular plate is optim ized by properly choosing the material properties and dimensions of th e plate such that the eigenfrequency of the first centrally symmetric resonance of the plate corresponds to the frequency where the plate ra diates acoustic energy the most efficiently. It is hoped that the meth odology will prove effective in designing high intensity sound sources .