Influence of cavitation on ultrasonic piezoelectric transducers impedance: Modelling and experimentation

Piezoelectric transducers for ultrasonic applications in liquid media are subjected to hard environmental and operational conditions. Indeed, they are often driven at high voltage and operate in non-linear environments. The application of ultrasounds to a liquid causes the appearance of cavitation, harmful to the transducer and strongly nonlinear. In this paper, an analysis of the influence of cavitation on a transducer electrical impedance is carried out using two modeling methods and an experimental confirmation. The final objective of this analysis is to give the piezoelectric transducer a sensing function, so that it can give relevant information on the evolution of the fluid physical properties particularly the evolution of the volume fraction of gase in the fluid during cavitation process.