Acoustic Refraction and Scattering with Compliant Elements. I. Measurements in Water; II. Analysis.

摘要

The velocity of sound in water may be reduced markedly with mechanical structures which effectively increase the compressibility of water. A compliant tube, formed from commerically available round tubing by deforming its cross section elliptically, is a simple example of such a structure. Compliant tubes are useful in the design of lenses at frequencies below the lowest flexural resonant frequency of a compliant tube immersed in water and reflectors for frequencies up to where the spacing between adjacent compliant tubes corresponds to a half-wavelength. Several measuring techniques were utilized to demonstrate the different aspects of compliant tubes under various conditions of interest. (Author)