Multifrequency Langevin-Type Ultrasonic Transducer

Classical Langevin-type transducers used in various ultrasound systems to generate high-power ultrasonic vibrations have one operating frequency corresponding to the half-wave resonance in the transducer structure. In this paper, the design of a Langevin-type transducer with four operating frequencies in the range of 20–70 kHz, which correspond to the four flexural modes of transducer’s front mass, is proposed and investigated. A transducer prototype was developed and optimized using the finite element method. The transducer was then manufactured and studied experimentally. The results have shown that the transducer provides effective selective excitation of ultrasonic vibrations at the four frequencies.