Methods of Experimental Investigation of Acoustical Interactions between Electroacoustical Transducers in Arrays

Determining acoustical loading conditions on radiators in an underwater array is of great importance to predict the performance of the array. Acoustical interactions between radiators generate a non-uniform distribution of acoustic loading over the radiating surface of the array and often cause performance degradation on the directivity patterns as well as the transmit frequency response of the array. In the electromechanical equivalent circuit model of such an array, the influence of the radiation of the neighboring radiator transducers can be considered as a mutual radiation impedance that is an intrinsic property of a given transducer and array configuration. Our goal in this project is to improve experimental techniques to determine both active and reactive parts of mutual radiation impedances. Two experimental methods are presented based on the measurements of the coupled impedance (“Z-method”) and the acousto-motive force (“V-method”). For both methods, analytical investigations based on the electromechanical equivalent circuit analysis are shown. PACS Numbers: 43.38.Hz, 43.38.Ar, 43.38.Fx, 43.38.Pf, 43.30Yj