Parametric acoustic sources of rectangular aperture

Abstract

A model is presented for predicting source levels and beam patterns generated by parametric acoustic sources of rectangular aperture. This model is a generalization of a previous model for square and circular apertures [J. Acoust. Soc. Am. 61, 325–337 (1977)]. Because the nonlinear absorption of the primary beams is less for a rectangular projector than for a square projector of equal area and primary source level, it is possible to obtain larger difference-frequency source levels from rectangular projectors than from their square (or circular) couterparts. The conditions required for such enhanced source levels are discussed, and the results of an experimental test of the model are presented.