THEORETICAL AND EXPERIMENTAL STUDY OF THE EFFICIENCY OF AN ULTRASONIC TRANSDUCER

This paper deals with the efficiency of ultrasonic transducer whose radiating face vibrates uniformly and that can therefore be described by a quadripole model. It is shown that, by matching the load impedances, the transducer efficiency can be increased up to a maximum value denoted M. Then, an original method is proposed to deduce the maximum efficiency M from electrical impedance measurements. The particular load impedance leading to the upper limit M can easily be determined and it is also possible to evaluate the efficiency for any operating conditions. The results obtained with different transducers are presented and the possible applications of these measurements are discussed.