Algorithm-Based Method for Suppressing the Transmission of Sound in a Water-Filled Waveguide

Abstract

Harmonic waves propagating in a water-filled cylindrical waveguide are suppressed by an actuator-sensor combination. The actuator and sensor are made from a material consisting of piezoelectric particles suspended in an elastomer matrix. The feed back mechanism is based on an algorithm originating in the evaluation of complex roots of an analytic function. It does not depend on a model for the experimental arrangement. Results are presented for frequencies varying from 100 to 5000 Hz. Although it is not needed for the operation of the method, a mathematical model is offered that illustrates the wave interaction and provides a comparison of the merits of the active material used with other candidates.