Accession Number : ADA114816

Title :   The Prediction of Transducer Element Performance from In-Air Measurements.

Descriptive Note : Master's thesis,

Corporate Author : PENNSYLVANIA STATE UNIV UNIVERSITY PARK APPLIED RESEARCH LAB

Personal Author(s) : Schafer,Mark Evan

PDF Url : ADA114816

Report Date : 19 Jan 1982

Pagination or Media Count : 109

Abstract : A technique has been developed which accurately predicts the performance of underwater acoustic arrays prior to array construction. The technique is based upon the measurement of lumped-parameter equivalent circuit values for each element in the array, and is accurate in predicting the array transmit, receive and beam pattern response. The measurement procedure determines the shunt electrical and motional circuit elements from electrical imittance measurements. The electromechanical transformation ratio is derived from in-air measurements of the radiating face velocity and the input current to the transducer at resonance. The equivalent circuit values of a group of Tonpilz-type transducers were measured, and the self and mutual interaction acoustic loadings for a specific array geometry were calculated. The response of the elements was then predicted for water-loaded array conditions. Based on the predictions, a selection scheme was developed which minimized the effects of inter-element variability on array performance. The measured transmitting, receiving and beam pattern characteristics of a test array, built using the selected elements, were compared to predictions made before the array was built. The results indicated that the technique is accurate over a wide frequency range. (Author)

Descriptors :   *Transducers, *Performance(Engineering), *Measurement, *Air, *Predictions, Acoustic arrays, Arrays, Electromechanical devices, Ratios, Circuits, Equivalent circuits, Value, Broadband, Frequency, Underwater acoustics

Subject Categories : Electrical and Electronic Equipment
      Test Facilities, Equipment and Methods

Distribution Statement : APPROVED FOR PUBLIC RELEASE